Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: TheBoy on 05 May 2011, 12:23:02

Title: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 12:23:02
Seeing as its LPG, should I stick to the quads, or get twins? If twins, are they the same as what goes in the MV6?
Title: Re: What plugs to fit in my 3.2?
Post by: Jimbob on 05 May 2011, 12:37:26
Twins - stronger spark possible iirc.

(and all Mark fits in anything iirc)

I beleive same as your mv6 yes.

Title: Re: What plugs to fit in my 3.2?
Post by: hotel21 on 05 May 2011, 12:43:31
Quads in mine but purchased and fitted before I learnt from Mr DTM that the twins were probably the best option, performance wise, rather than the quads for longevity.

That said, mine are working quite fine, thanks...   ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Jimbob on 05 May 2011, 12:48:17
Quote
Quads in mine but purchased and fitted before I learnt from Mr DTM that the twins were probably the best option, performance wise, rather than the quads for longevity.

That said, mine are working quite fine, thanks...   ;D


snap
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 12:55:15
I use quads in mine on LPG with no issues.
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 13:32:35
Odd, I notice they list 2 different plugs for 3.0, based on engine number... ...why would they change the temp of the plug?
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 14:24:30
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Odd, I notice they list 2 different plugs for 3.0, based on engine number... ...why would they change the temp of the plug?

Beats me.  :-/ Change in ignition leads as well, perhaps? Can't think of a significant change in engine spec or service regime that would have prompted it, and if they found a problem with one plug recommendation they would have changed it retrospectively? :-/
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 14:28:13
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Odd, I notice they list 2 different plugs for 3.0, based on engine number... ...why would they change the temp of the plug?

Beats me.  :-/ Change in ignition leads as well, perhaps? Can't think of a significant change in engine spec or service regime that would have prompted it, and if they found a problem with one plug recommendation they would have changed it retrospectively? :-/
Guessing it was around the time when they modified oil pump and oil jets in the heads?

So would you chuck in twins or quads (about same price) - she is swing by dealer on way home from work...
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 14:33:07
I suspect either would be fine. I'm not helping, am I?

I would have tried twins last time if I'd remembered to look up the part number. ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 05 May 2011, 14:42:28
Cant see the point in paying the extra for quads given that you are unlikely to let them stay in place for longer than 40K miles (and they tend to come loose well before the 80K interval).

They potentialy shield the flame front.

I have a set of 6 new ones if you want them
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 14:51:06
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Cant see the point in paying the extra for quads given that you are unlikely to let them stay in place for longer than 40K miles (and they tend to come loose well before the 80K interval).

They potentialy shield the flame front.

I have a set of 6 new ones if you want them
The quads are only a few pence more...  ...but being anal, I like to change the plugs at 20k/2yrs anyway, whatever GM state.

It was the spark shielding I was concerned about, hence the Q.  I'll get her to pick 6 twins up from Stealers on the way home - TBE is recording misfires on No5 occasionally (along with flashing EML sometimes), so guessing the plugs (probably original) are past there best.


For reasons I dont want to go in to just yet, I don't want to touch the engine in any way until after tomorrow ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 16:11:14
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The quads are only a few pence more...  ...but being anal, I like to change the plugs at 20k/2yrs anyway, whatever GM state.
Well, the quads come out looking brand new after 40k, so no problems there with either, I'd imagine. ;D

Quote
For reasons I dont want to go in to just yet, I don't want to touch the engine in any way until after tomorrow ::)

 :-?
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 16:43:14
She's picked up half a dozen twins (and some of tunnie's junk, and paid for it :o) from dealer, so we will see how we get on.


I suspect the quads in there are shot, judging by the missfires it keeps recording. Suspect original at 59k.  Or the coil pack has let go...  ...now you mention it, its only ever recorded misfires on drivers bank... ...and only on LPG...
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 16:48:13
I guess you'll see problems on LPG first. Not sure there's much of an issue with the plugs lasting the distance but it's time to change them without a doubt.

Bet you won't need a socket to unscrew them, though. :o
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 17:11:57
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I guess you'll see problems on LPG first. Not sure there's much of an issue with the plugs lasting the distance but it's time to change them without a doubt.

Bet you won't need a socket to unscrew them, though. :o
It was all fine until I gave chrisgixer the keys whilst I had a chat with Albs ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 05 May 2011, 20:05:20
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I guess you'll see problems on LPG first. Not sure there's much of an issue with the plugs lasting the distance but it's time to change them without a doubt.

Bet you won't need a socket to unscrew them, though. :o
It was all fine until I gave chrisgixer the keys whilst I had a chat with Albs ;D

Has it got any fuel in it? ;D

.. or maybe it's been "gravelled"? :-X
Title: Re: What plugs to fit in my 3.2?
Post by: tunnie on 05 May 2011, 20:17:58
twins in mine, done well over 40k, think around 50k by now :o  ;D

Really should change them!
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 20:33:49
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I guess you'll see problems on LPG first. Not sure there's much of an issue with the plugs lasting the distance but it's time to change them without a doubt.

Bet you won't need a socket to unscrew them, though. :o
It was all fine until I gave chrisgixer the keys whilst I had a chat with Albs ;D

Has it got any fuel in it? ;D

.. or maybe it's been "gravelled"? :-X
I had more sense that bob.dent - mine was running on LPG, though it came back with EML one  >:(   ;D
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 20:34:31
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twins in mine, done well over 40k, think around 50k by now :o  ;D

Really should change them!
Yes! Stated life is 40k for twins, I'd change them at 20k, esp with LPG.
Title: Re: What plugs to fit in my 3.2?
Post by: tunnie on 05 May 2011, 20:35:33
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twins in mine, done well over 40k, think around 50k by now :o  ;D

Really should change them!
Yes! Stated life is 40k for twins, I'd change them at 20k, esp with LPG.

They had been in a while when it was converted, I would have put new ones in, but some git nicked most of mine  ::)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 05 May 2011, 20:45:21
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twins in mine, done well over 40k, think around 50k by now :o  ;D

Really should change them!
Yes! Stated life is 40k for twins, I'd change them at 20k, esp with LPG.

They had been in a while when it was converted, I would have put new ones in, but some git nicked most of mine  ::)
Best you buy some then ;D
Title: Re: What plugs to fit in my 3.2?
Post by: 05omegav6 on 06 May 2011, 00:50:30
Only ever put quads in mine, upto last service. Put twins in and it promptly ate one. >:( All 6 swiftly replaced with quads. Not eaten any since. (feverishly touching wood.). :-X

Not sure that the plugs themselves were to blame, but quite a coincidence... :-/
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 06 May 2011, 01:05:31
Quads, always quads,....   me and LD loosened the easy to reach ones when he wasn't looking. Shhhhhh.  :-X

Mind you, try as we mite we only managed an 0300.

Don't forget the wind screen seal was loose btw. Might be some rust/water damage maybe?  :-/
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 06 May 2011, 11:09:42
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The quads are only a few pence more...  ...but being anal, I like to change the plugs at 20k/2yrs anyway, whatever GM state.
Well, the quads come out looking brand new after 40k, so no problems there with either, I'd imagine. ;D

Quote
For reasons I dont want to go in to just yet, I don't want to touch the engine in any way until after tomorrow ::)

 :-?

Interestingly, I stuck some under teh microscope at work to look at and you can clearly see some errosion of the centre electrode adjacent to the outer electrodes.

Despite this, they worked fine and looked ok.
Title: Re: What plugs to fit in my 3.2?
Post by: Martin_1962 on 06 May 2011, 12:53:33
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She's picked up half a dozen twins (and some of tunnie's junk, and paid for it :o) from dealer, so we will see how we get on.


I suspect the quads in there are shot, judging by the missfires it keeps recording. Suspect original at 59k.  Or the coil pack has let go...  ...now you mention it, its only ever recorded misfires on drivers bank... ...and only on LPG...


SNAP!
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 06 May 2011, 18:31:53
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Quads, always quads,....   me and LD loosened the easy to reach ones when he wasn't looking. Shhhhhh.  :-X

Mind you, try as we mite we only managed an 0300.

Don't forget the wind screen seal was loose btw. Might be some rust/water damage maybe?  :-/
Lightweight! I've lit up that entire 1/3/5 bank  :-[, suspect when I remove coil pack this weekend it will be knackered.  Not even 60k...

Still, I can now touch the engine  :-X, so that could be this weekend's job ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 06 May 2011, 18:50:02
Whats up, couldn't get the bonnet open?
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 07 May 2011, 10:16:23
Whilst in the LPG place, they had loads of bumpth on NGK Laserline plugs, especially for LPG...

...though at £20 a pop, I don't think I'll go for them ;D
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 07 May 2011, 10:18:49
Also, whilst in there, there was a customer with a Merc V8, just been converted.  It seems they change the plugs at conversion as a matter of course?  He'd not long had it serviced by Merc, who had changed all the plugs, so he was having these newish ones that came out as spares...  ...all 16 of them :o  (2 plugs per cylinder)
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 07 May 2011, 11:24:47
No point in using any plugs other than GM at the price of them :y :y
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 07 May 2011, 14:08:50
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Also, whilst in there, there was a customer with a Merc V8, just been converted.  It seems they change the plugs at conversion as a matter of course?  He'd not long had it serviced by Merc, who had changed all the plugs, so he was having these newish ones that came out as spares...  ...all 16 of them :o  (2 plugs per cylinder)
Than sense money more.
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 10 May 2011, 21:14:29
What was the decision? I'm putting a little shopping list together for andyc (although he doesn't know yet :-X ::)) and go and collect it all before the end of the month ::)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 11 May 2011, 16:01:04
Bought twins
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 18:05:15
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Bought twins

Hmm... I'm placing an order with andyc tomorrow. May as well go for twins too... It's got to be the best compromise and best way to reduce spark shielding :-/
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 11 May 2011, 18:07:21
Can someone explane the shielding thing please?
Title: Re: What plugs to fit in my 3.2?
Post by: kcl on 11 May 2011, 18:20:28
why would GM put quad plugs in cars if twins were better?
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 18:24:25
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why would GM put quad plugs in cars if twins were better?

We're talking about an alternative fuel here ;) Both the cars in question have (or will have) LPG fitted which demands a stronger spark to ignite :y
Title: Re: What plugs to fit in my 3.2?
Post by: hotel21 on 11 May 2011, 18:25:49
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Can someone explane the shielding thing please?

The available plug area is only so much.

If there are two electrodes versus four electrodes competing for the available area, the two additional electrodes impinge on the flame front of the other two, despite having a flame/spark of their own.

Thats how I understand it, anyroads....   :-[
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 18:26:40
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Can someone explane the shielding thing please?

Basically the spark could potentially be completely inside the hollow of the end of the plug so twins have more open area than quads so less chance of the spark being "hidden" behind the electrodes.

Be interesting to stick quads in one and run a back to back comparison :-/
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 11 May 2011, 20:49:21
I think, personally, quads are fitted for longer life only - ISTR reading that the spark will only ever be between the centre electrode and one of the ground electrodes (at any given moment).. So with four grounds presumably you get longer life out of them as they're only hit a quarter of the time?

Then again I always thought it was the centre electrode that wore more (perhaps it wears more evenly)..

Still, I know plenty of cars that seem to hate quad electrode plugs - personally I've only ever fitted good quality copper electrode, single ground NGK plugs in anything I've had (and that includes the 75%-more-power-than-stock turbocharged MR2) and never had a problem.. Granted I haven't done the Omega yet!
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 21:16:40
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I think, personally, quads are fitted for longer life only - ISTR reading that the spark will only ever be between the centre electrode and one of the ground electrodes (at any given moment).. So with four grounds presumably you get longer life out of them as they're only hit a quarter of the time?

Then again I always thought it was the centre electrode that wore more (perhaps it wears more evenly)..

Still, I know plenty of cars that seem to hate quad electrode plugs - personally I've only ever fitted good quality copper electrode, single ground NGK plugs in anything I've had (and that includes the 75%-more-power-than-stock turbocharged MR2) and never had a problem.. Granted I haven't done the Omega yet!

I stuck NGK single electrodes into the Omega (after LPGing it) once as a trial and there was no improvement over GM twins that were cheaper ;)

AFAIK you're right about quads being for life, but as I'll be changing them annually anyway I can get away with twins :y
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 11 May 2011, 21:28:21
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 11 May 2011, 21:42:33
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 21:49:01
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Quote
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/

Twins give 40k, quads give 80k... In theory ::)

Don't completely understand why it shields it, but that's the theory. In reality I don't really see much difference but as the twins are slightly cheaper and I change them annually I'll go with them :y :y
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 11 May 2011, 21:52:32
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Quote
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/

The ground prongs are the 'shield' between the spark and the piston crown.. The spark is vertical between the centre electrode and a random ground prong, the other three ground prong ends are essentially shielding it from the cylinder.

(Well that's the theory, anyway)
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 11 May 2011, 21:59:25
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I stuck NGK single electrodes into the Omega (after LPGing it) once as a trial and there was no improvement over GM twins that were cheaper ;)

True, if GM twins are cheap you might as well use them :) The Omega is hardly a highly tuned powerhouse ;) even with LPG I doubt the ignition system is at all 'marginal'

I switched to NGK copper plugs in the other cars that specified (expensive!) Iridium or Platinum plugs, though :) (those are also specified for service interval reasons only; they give a weaker spark than copper AFAIK)
Title: Re: What plugs to fit in my 3.2?
Post by: Andy B on 11 May 2011, 22:07:10
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... The spark is vertical between the centre electrode and a random ground prong, the other three ground prong ends are essentially shielding it from the cylinder.

(Well that's the theory, anyway)

Have never looked at a twin or quad plug then? You theory holds for the old style single earth plug, but the twin & quad plugs have the earth arranged around the outside of the central electrode so the spark is horizontal between the 2 or 4.
I'm with Chris (as long as he uses a bit of copper slip when he refits them  ;)) as the combustion chamber will see as much spark from a quad as it will see from a twin.
However when I removed my quads last year after a couple of years  (20/25k miles??? :-/) they looked quite 'worn' so I replaced them with twins.

but WTF do I do ????  :-/
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 11 May 2011, 22:31:26
I guess 'new' quads are different from the ones I looked at 10+ years ago then (which were exactly like I described).. does answer how they reduce wear on the centre electrode then (since you'd be eroding four sides of it rather than the top of it, IYSWIM)
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 11 May 2011, 22:32:26
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Quote
Quote
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/

Twins give 40k, quads give 80k... In theory ::)

Don't completely understand why it shields it, but that's the theory. In reality I don't really see much difference but as the twins are slightly cheaper and I change them annually I'll go with them :y :y
Yes, TB has it fuddled again. That was my point. Silly.  ;D
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 11 May 2011, 23:02:18
Quote
I guess 'new' quads are different from the ones I looked at 10+ years ago then (which were exactly like I described).. does answer how they reduce wear on the centre electrode then (since you'd be eroding four sides of it rather than the top of it, IYSWIM)
No mate, the spark is horizontal or parallel to the piston crown radiating out from the centre.
(http://i344.photobucket.com/albums/p326/chrisgixer/e02d3d40.jpg)
Theres nout there to shield the spark. Quads for me thanks. 
Title: Re: What plugs to fit in my 3.2?
Post by: Andy B on 11 May 2011, 23:08:21
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....
Theres nout there to shield the spark. Quads for me thanks. 

You'll be struck down for disagreeing with OOF hierarchy ...............  ::) ::) ::) ::) ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 11 May 2011, 23:14:11
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Quote
....
Theres nout there to shield the spark. Quads for me thanks. 

You'll be struck down for disagreeing with OOF hierarchy ...............  ::) ::) ::) ::) ::)
Having said I'll go for twins, I might change my order to quads and we can do a side by side comparison with TB's... At the end of the day, it's only pennies in it price wise :-/
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 11 May 2011, 23:48:29
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Quote
Quote
....
Theres nout there to shield the spark. Quads for me thanks. 

You'll be struck down for disagreeing with OOF hierarchy ...............  ::) ::) ::) ::) ::)
Having said I'll go for twins, I might change my order to quads and we can do a side by side comparison with TB's... At the end of the day, it's only pennies in it price wise :-/
Not the money as you say. Just want to understand what we're talking about here. Logic, or my logic anyway, says quads all day.... For twice the miles...? In theory. ;)

Reality might be more 40k for quads, 20 for twins? ESP if lpg'd...? <- note. Question. Not a statement. I don't trust vx's desire to lengthen established service schedules to suit fleet managers budgets.
Title: Re: What plugs to fit in my 3.2?
Post by: hotel21 on 12 May 2011, 00:45:32
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Quote
....
Theres nout there to shield the spark. Quads for me thanks. 

You'll be struck down for disagreeing with OOF hierarchy ...............  ::) ::) ::) ::) ::)
Hardly...

Personally, was giving an individual understanding, nowt else.

And I can do those smileys too.... 

 ::) ::) ::) ::) ::)

 ;D   :y
Title: Re: What plugs to fit in my 3.2?
Post by: Andy B on 12 May 2011, 01:26:54
Quote
....
Hardly...

Personally, was giving an individual understanding, nowt else.

And I can do those smileys too.... 

 ::) ::) ::) ::) ::)

 ;D   :y

I wasn't really thinking of you .....  ;)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 08:12:47
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Quote
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why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/

Twins give 40k, quads give 80k... In theory ::)

Don't completely understand why it shields it, but that's the theory. In reality I don't really see much difference but as the twins are slightly cheaper and I change them annually I'll go with them :y :y
I think quads are marginally cheaper, but the cost is not relevent here, as its only pence.
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 08:16:20
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Quote
Quote
Quote
Quote
why would GM put quad plugs in cars if twins were better?
To extend the plug life to a supposed 80k. Shame they are all loose by 60k...
So twins give 80k life? In theory?

I see the theory on doubling the number of electrodes to spread the wear over 4 instead of two. Got that, that's why i fit quads.

I have trouble understanding how a cylinder full of compressed fuel by a ratio of 11.1 or whatever it is will ignite worse with two extra electrodes.... ? the spark radiates around the four, facing the piston. I don't get it. The flame front starts with spark. Theres nothing between it and the piston crown.

Surely? What am I not seeing ?  :-/

Twins give 40k, quads give 80k... In theory ::)

Don't completely understand why it shields it, but that's the theory. In reality I don't really see much difference but as the twins are slightly cheaper and I change them annually I'll go with them :y :y
Yes, TB has it fuddled again. That was my point. Silly.  ;D
Eh? How can so many people misread that?

GM put quads in to extend the inteval from the (over optimistic) 40k to the even more over optimistic 80k....


....simples....
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 08:19:16
I believe the theory is, the more bits sheilding the spark from the fuel in all directions, rather than just the downward side, the worse the plug is for its function.


Note, LPG specific plugs, such as NGK Laserline, are single electrode...
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 12 May 2011, 08:20:17
Nobody has said it shields the spark, it does shield the flame front....

Given the denisty of fuel air mix once compressed there is always going to be something to ignite, its the speed that the flame can spread to the rest of teh mix that is impeded.

Just remember, these plugs were ONLY fitted to get the service interval upto 80K miles....i.e. above the 60K mile benchmark the fleet operators look at (similarly the twins were fitted to get the interval upto 40K)
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 12 May 2011, 09:47:28
And we're discarding them over the benefits because of that...?
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 12 May 2011, 10:41:57
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And we're discarding them over the benefits because of that...?

Thats the key thing, there are no REAL benefits as the quads require attention before the 80k interval is reached due to them working loose.

In addition, there is the potential for them to slow the flame front.

Hence, you can infer that they are not worth bothering with.  :y
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 11:15:50
I knew someone with better knowledge would explain it better ::) ;D

I'll stick with the whatever I get as they'll only be in a year or so anyway
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 12 May 2011, 13:29:37
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And we're discarding them over the benefits because of that...?

Thats the key thing, there are no REAL benefits as the quads require attention before the 80k interval is reached due to them working loose.

In addition, there is the potential for them to slow the flame front.

Hence, you can infer that they are not worth bothering with.  :y
Depends if we believe the shielding theory. I wouldn't leave them in for 80 k anyway esp with lpg, as suggested earlier. Previous set where loose on other car, but I didn't know of the issue when I installed them, so didn't re tighten after the initial torque (25nm is it? ) when the washers relaxed.

It's only a potential shielding after all. I don't buy it personally ESP given the gap that's bigger than I visualized. But it's been an interesting topic.  ESP if it windes Andy B up   ;D.  sorry Andy  ;)  ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Marks DTM Calib on 12 May 2011, 14:38:09
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And we're discarding them over the benefits because of that...?

Thats the key thing, there are no REAL benefits as the quads require attention before the 80k interval is reached due to them working loose.

In addition, there is the potential for them to slow the flame front.

Hence, you can infer that they are not worth bothering with.  :y
Depends if we believe the shielding theory. I wouldn't leave them in for 80 k anyway esp with lpg, as suggested earlier. Previous set where loose on other car, but I didn't know of the issue when I installed them, so didn't re tighten after the initial torque (25nm is it? ) when the washers relaxed.

It's only a potential shielding after all. I don't buy it personally ESP given the gap that's bigger than I visualized. But it's been an interesting topic.  ESP if it windes Andy B up   ;D.  sorry Andy  ;)  ;D

Lol, its a slow down of the flame front, which I can see happening as the flame is shielded from the mix on the outer part of the electrode. The actual initial ignition wont be any different.
Title: Re: What plugs to fit in my 3.2?
Post by: Andy B on 12 May 2011, 15:30:47
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....  ESP if it windes Andy B up   ;D.  sorry Andy  ;)  ;D

Doesn't bother me either way. ;) I've had twins in, fitted quads and replaced them after nothing like 80k & gone back to twins. I've never had plugs come loose (last time I had a loose plug was 1980 in my GT250  ;D & that was a single.)
IMO once the flame front has set off, the spark plug has no further influence whether it's a single, twin, quad or even 2 plugs like her Smart.
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 12 May 2011, 15:46:22
It really isn't worth 5 pages of worrying about, IMHO.  ;)

If the flame front is delayed, the effect is to slightly retard the ignition timing. Given that the car was sold with quad plugs that's probably what the engine was running when the ECU calibration was made, so, if there's a significant effect, it's already compensated for.

Kevin
Title: Re: What plugs to fit in my 3.2?
Post by: Andy B on 12 May 2011, 15:49:03
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It really isn't worth 5 pages of worrying about, IMHO.  ;) ......

Who's worried?  ::) ::) ::)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 16:12:54
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It really isn't worth 5 pages of worrying about, IMHO.  ;)

If the flame front is delayed, the effect is to slightly retard the ignition timing. Given that the car was sold with quad plugs that's probably what the engine was running when the ECU calibration was made, so, if there's a significant effect, it's already compensated for.

Kevin
retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 12 May 2011, 16:15:28
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 16:16:58
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
A race?  I wouldn't be so immature ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 16:21:42
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
A race?  I wouldn't be so immature ::)

Brackley to a meet perhaps :-X :-X ::) ::) ;D ;D
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 12 May 2011, 17:02:07
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 17:04:12
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)
Some smart arse said it would have made sense to do the cambelt as well
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 17:05:05
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)

Ahh... So it was related to the EML we managed to get up then :D :D :D

I've got quads on order and the mileage on them will be pretty similar if TB changes the twins at the same mileage I change the quads (because I'll get there before him ::)) at, shall we say 30k, and we'll ask the master to do a direct comparison :y
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 17:06:17
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)

Ahh... So it was related to the EML we managed to get up then :D :D :D

I've got quads on order and the mileage on them will be pretty similar if TB changes the twins at the same mileage I change the quads (because I'll get there before him ::)) at, shall we say 30k, and we'll ask the master to do a direct comparison :y
Mine get changed bi-annually normally, so around 20-25k... ...that said, TBE doesn't do many miles....
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 17:06:33
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)
Some smart arse said it would have made sense to do the cambelt as well

Mine's due in about 4 months (although it's only done 26k on it) but thought it would be extracting the urine a little to try and get that done at the same time as everything else :-X ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 17:08:34
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retarding the ignition sounds like taking away some of my precious GGs....  ....so that be fighting talk, Mr Wood :P ;D

.. Only if they didn't calibrate the ECU with the quads. ;)

TBH, it's all speculation, though. A back to back test is the way to sort things like this out. ;)
Bah, there'll be break all difference. So may as well have the extra life, as Mr Gm intended.  :)

I'll fit quads, well, I have already, knowing LPG was on the way it obviously makes sense to check your ignition system first. BEFORE the install.  ::)

There in lies a clue. ;)

Ahh... So it was related to the EML we managed to get up then :D :D :D

I've got quads on order and the mileage on them will be pretty similar if TB changes the twins at the same mileage I change the quads (because I'll get there before him ::)) at, shall we say 30k, and we'll ask the master to do a direct comparison :y
Mine get changed bi-annually normally, so around 20-25k... ...that said, TBE doesn't do many miles....

So I'll just pull mine out after a year then :-X ::)... Actually, scrub that. Shall I go for 2 years (40-45k ish) and compare? They're supposed to last twice as long :-?
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 17:09:22
May as well do the cambelt whilst the plenum is off.  We get as far as we get, its a new install, so doubt it'll be finished in the alloted time TBH - the rear is going to take some planning and time...
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 12 May 2011, 17:11:02
Apart from a massive gap and a slightly squared electrode, my quads didn't look to bad at 60k...  ...loose as break though - and if you're going to the effort to retorque them regularly, may as well change them
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 17:29:03
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May as well do the cambelt whilst the plenum is off.  We get as far as we get, its a new install, so doubt it'll be finished in the alloted time TBH - the rear is going to take some planning and time...

Actually, it's looking promising (if the weather holds out), even though I can't make it 'till Saturday am... Got answers from both KW and Gixerboy saying they're available. So that's 4 people (3.5 actually with my back :-[) who know what they're doing :y Manifold and Loom will be prepared in advance and we know exactly where to put everything (front end wise) as it's identical to yours ;) Got the required heater hose from andyc so that's that sorted :y

Rear end wise... I'll probably have to bite the bullet and pay through the nose (extra £75+VAT over the 76L) for the 72L tank, although I'm awaiting a call from cliffob to confirm some details, which should drop straight into the well :y

No holes to cut :y so just the towbar to stick on (if I haven't done it in advance) and we're away... I reckon it might be doable :-/ Admittedly it'll be a couple of longish days, but should be doable, with the final touches on Monday.

Obviously I'll have to sort out raising the boot floor at a later date but looking at the cost of petrol I'll just be grateful to be back on LPG! I'll fill up the petrol tank tonight (at about the same mileage as I could get out of LPG, possibly slightly less) to remind myself! :'( :'(
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 17:30:37
Oh... But we will have to drop the petrol tank a bit/lot... I'll probably be nipping up a bit when I arrive at yours trying to get as little fuel in it as possible ::) ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Kevin Wood on 12 May 2011, 20:43:52
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Oh... But we will have to drop the petrol tank a bit/lot... I'll probably be nipping up a bit when I arrive at yours trying to get as little fuel in it as possible ::) ::)

I remember when we did Marie's estate. "So, we're going to have to drop the tank." <looks at gauge - full to the brim> "Have we got anything that'll soak up 70 litres of petrol?" <all eyes turn to JamesV6's V8 Disco on the driveway.> ;D
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 21:16:21
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Oh... But we will have to drop the petrol tank a bit/lot... I'll probably be nipping up a bit when I arrive at yours trying to get as little fuel in it as possible ::) ::)

I remember when we did Marie's estate. "So, we're going to have to drop the tank." <looks at gauge - full to the brim> "Have we got anything that'll soak up 70 litres of petrol?" <all eyes turn to JamesV6's V8 Disco on the driveway.> ;D

I intend to turn up with as little as possible in the tank, assuming I get my calculations right ::)

Either that or someone will get a call to bring me a can of petrol :-X ::)
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 22:28:14
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May as well do the cambelt whilst the plenum is off.  We get as far as we get, its a new install, so doubt it'll be finished in the alloted time TBH - the rear is going to take some planning and time...

Thinking on the cambelt some more... I'm getting all the bits for camcover gasket change as well but don't intend to do it, just figured I may as well pick it up while I was doing a big shopping list ::)

We'll take a view on it, assuming I've found a kit at a decent price, as the plan was to do cambelt and water pump at The Lakes/Newent if I can't make it to the Lakes. I can always do it at home if needs be ;)

Do need to do a coolant flush when we do the LPG though as it's got blue antifreeze in it ::) And stick the new plugs in while we've got the plenum/inlet off for ease of access :y

TBH, I'd rather concentrate on the LPG and do the rest later... Got 13k on the current one (although only 3.5 months) so it can wait if it looks like time may be short ;)

I'm hoping to get the tow bar fitted beforehand anyway, so that just leaves the tank to get fitted at the back end. :y
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 12 May 2011, 23:20:13
Cam cover seals
Cam belt
Water pump
Plugs
Breathers
Coolant flush
Filters?
Lpg front end
Bag of gravel
Tow bar
break about with rear end tank


What could possibly go wrong?  :-X  ;D

Who's car is this btw?
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 12 May 2011, 23:27:19
Cam cover seals - Not Urgent, just getting the parts
Cam belt - Again, not urgent
Water pump - Yet again, Not urgent
Plugs - Simple enough with everything removed
Breathers - Visual check and put right the mucking fuddle at the back
Coolant flush - It'll be drained a fair bit anyway ::)
Filters? - Only Air and Pollen, possibly petrol
Lpg front end - Yes please!
Bag of gravel - break Orff :D :D
Tow bar - Might be done ;)
break about with rear end tank - Think it'll be easier than I thought


What could possibly go wrong?  :-X  ;D - It'll be fine :-? ::)

Who's car is this btw? - Not myMy car!! :y :y
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 13 May 2011, 00:28:35
Cam covers seals and cam belt are half way there given the work, has to be said. May as well...?
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 13 May 2011, 07:28:16
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Cam covers seals and cam belt are half way there given the work, has to be said. May as well...?
Yeah, I know :-/ Not convinced the cam covers are leaking, other than a very slight weep from one bolt (possibly) :-/ Just figured I may as well order up a complete kit for "stock" as they're bound to need doing at some point ::) Do need to sort the breathers though... It looks like some monkey has put a tee piece into one of the breathers and attached the gearbox breather to it ::) Got replacement pipes though :y

Cam Belt... I suppose it's only a fairly quick job with everything stripped off that is already off so it might be an idea to just get it done... At the end of the day it'll take a short while for 1 person and other bits and pieces can still be done on the LPG side :y I'll make sure I've got a kit ;)
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 13 May 2011, 09:58:47
All this talk of plugs got me thinking (this morning, on the way to work) - I should really do the other cam cover (as the car smells like someone set light to an Iraqi oil field after a drive) and should probably do the plugs at the same time really given they're probably 80k old..

Now what to buy.. quads, duals or singles..  ;D
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 13 May 2011, 10:10:12
I don't do cam cover gaskets. I hate that bloody job.  Did I mention I hate that bloody job.

Still, its not my car.

But lastly, I hate that bloody job.

Twice in 2 months is enough for me, as I hate that bloody job.
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 13 May 2011, 10:12:01
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I don't do cam cover gaskets. I hate that bloody job.  Did I mention I hate that bloody job.

Still, its not my car.

But lastly, I hate that bloody job.

Twice in 2 months is enough for me, as I hate that bloody job.

I'm not a fan of it either TBH... But I'm still not convinced they're leaking... Not had a thorough check due to incapacity but at a glance and quick feel they seem OK
Title: Re: What plugs to fit in my 3.2?
Post by: TheBoy on 13 May 2011, 10:15:14
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I don't do cam cover gaskets. I hate that bloody job.  Did I mention I hate that bloody job.

Still, its not my car.

But lastly, I hate that bloody job.

Twice in 2 months is enough for me, as I hate that bloody job.

I'm not a fan of it either TBH... But I'm still not convinced they're leaking... Not had a thorough check due to incapacity but at a glance and quick feel they seem OK
Mine had a visible leak from a bolt on 1/3/5 bank - turned out it was a lose bolt.

No visible sign of a leak from 2/4/6 - but it was the worse I have ever seen, never seen the oil under slight pressure before in the plug wells. I got covered :o
Title: Re: What plugs to fit in my 3.2?
Post by: Lazydocker on 13 May 2011, 10:18:21
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Quote
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I don't do cam cover gaskets. I hate that bloody job.  Did I mention I hate that bloody job.

Still, its not my car.

But lastly, I hate that bloody job.

Twice in 2 months is enough for me, as I hate that bloody job.

I'm not a fan of it either TBH... But I'm still not convinced they're leaking... Not had a thorough check due to incapacity but at a glance and quick feel they seem OK
Mine had a visible leak from a bolt on 1/3/5 bank - turned out it was a lose bolt.

No visible sign of a leak from 2/4/6 - but it was the worse I have ever seen, never seen the oil under slight pressure before in the plug wells. I got covered :o

Yep, visible weep from a bolt on 1/3/5 but nothing else seems wet. I'll have the bits with me just in case when we pull the plugs out they're having a bath! ;D
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 13 May 2011, 10:45:55
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Quote
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I don't do cam cover gaskets. I hate that bloody job.  Did I mention I hate that bloody job.

Still, its not my car.

But lastly, I hate that bloody job.

Twice in 2 months is enough for me, as I hate that bloody job.

I'm not a fan of it either TBH... But I'm still not convinced they're leaking... Not had a thorough check due to incapacity but at a glance and quick feel they seem OK
Mine had a visible leak from a bolt on 1/3/5 bank - turned out it was a lose bolt.

No visible sign of a leak from 2/4/6 - but it was the worse I have ever seen, never seen the oil under slight pressure before in the plug wells. I got covered :o

Yep, visible weep from a bolt on 1/3/5 but nothing else seems wet. I'll have the bits with me just in case when we pull the plugs out they're having a bath! ;D

I'm sure that's what I'm going to find when I do the passenger side - then again, I thought that's what I'd find in the drivers side.. but they were bone dry.

Still something smells of hot/burning oil/plastic..  :-/
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 13 May 2011, 10:58:24
Is the top of the sump wet under the crank pulley and round the sides? Usually leaks from the area around the front cam lobes and runs down the back of the rear cam belt cover. If you poke your hand down the side above the alternator, and then feel round the front of the engine there's usually oil there confirming failed seals. In variably there are loose cover bolts, and cars of this age the seals are rock hard anyway. Or certainly harder.
Title: Re: What plugs to fit in my 3.2?
Post by: feeutfo on 13 May 2011, 10:59:42
Although could the plastic smell be coolant? Burnt sugar smell, ish..?
Title: Re: What plugs to fit in my 3.2?
Post by: aaronjb on 13 May 2011, 11:14:25
Nah it's definitely a burning oil/plastic smell, very distinctive (plus I remember it well from the time I left the oil filler cap off on the MR2 and drove to work  :-[ ) - but I haven't managed to find any sticky areas yet aside from the back of the drivers bank before I changed that seal (and it's dry now)

Then again I didn't take the undertray off the last time I was under the car.

I'll poke around the alternator area and see what I find - cheers Chris :)