Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: kjf7 on 17 April 2009, 22:44:00

Title: timing chain or no t/chain that is the question
Post by: kjf7 on 17 April 2009, 22:44:00
hi all,
as above do i have one of these on my 2.5 td (bmw engine) 95 model as thats what a garage told me today cheers :-?
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 17 April 2009, 22:44:26
You have 2 timing chains on that engine
Title: Re: timing chain or no t/chain that is the question
Post by: Jimbob on 17 April 2009, 22:44:40
yup chain driven
Title: Re: timing chain or no t/chain that is the question
Post by: Slurpy on 18 April 2009, 06:29:37
definately chain
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 18 April 2009, 10:57:48
And another reason to change the oil in this unit very, very regularly (ie every 3k)
Title: Re: timing chain or no t/chain that is the question
Post by: Lizzie_Zoom on 18 April 2009, 11:00:03
Ah.........lovely echoes of the Senny!!  

I miss the chains!! :'( :'(   Why do cars still have to be fitted with 'rubber bands' instead of sensible, long lasting, chains?? :-? :-? :-?
Title: Re: timing chain or no t/chain that is the question
Post by: Andy B on 18 April 2009, 11:02:02
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..... instead of sensible, long lasting, chains?? :-? :-? :-?

12 valve long lasting duplex or 24 valve not quite so long lasting simplex?   :y  :y  :y
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 18 April 2009, 11:02:39
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Ah.........lovely echoes of the Senny!!  

I miss the chains!! :'( :'(   Why do cars still have to be fitted with 'rubber bands' instead of sensible, long lasting, chains?? :-? :-? :-?
Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.
Title: Re: timing chain or no t/chain that is the question
Post by: Lizzie_Zoom on 18 April 2009, 11:05:46
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Quote
Ah.........lovely echoes of the Senny!!  

I miss the chains!! :'( :'(   Why do cars still have to be fitted with 'rubber bands' instead of sensible, long lasting, chains?? :-? :-? :-?
Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.


Yes maybe, but my old Senny, at 250k on the clock, still had the original chain fitted and the Vx dealer (then an excellent one) told me that they rarely replaced the chains; just keep the engine well oiled! 8-) 8-)

The engine was still producing top speeds of 145 mph. :-* :-* 8-)
Title: Re: timing chain or no t/chain that is the question
Post by: Andy B on 18 April 2009, 11:06:16
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......

Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.

So you've said before ........ I ain't convinced.  ;)  ;)
You come across more cars where the rubber bands have snapped than you ever did with chains snapping. I ain't coninced over the stretched chains either ... they sit it their own oil bath.  :y
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 18 April 2009, 11:10:33
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Quote
Quote
Ah.........lovely echoes of the Senny!!  

I miss the chains!! :'( :'(   Why do cars still have to be fitted with 'rubber bands' instead of sensible, long lasting, chains?? :-? :-? :-?
Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.


Yes maybe, but my old Senny, at 250k on the clock, still had the original chain fitted and the Vx dealer (then an excellent one) told me that they rarely replaced the chains; just keep the engine well oiled! 8-) 8-)

The engine was still producing top speeds of 145 mph. :-* :-* 8-)
And we've all heard of rubber band cars doing 150k on same band ;). And as those same bands will never stretch, they too will be capable of any performance it had when newer...
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 18 April 2009, 11:17:05
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Quote
......

Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.

So you've said before ........ I ain't convinced.  ;)  ;)
You come across more cars where the rubber bands have snapped than you ever did with chains snapping. I ain't coninced over the stretched chains either ... they sit it their own oil bath.  :y
Generally, the belts don't snap, its normally a bearing that gives up the ghost ;).

Generally, the chains only snap with extreme age - particularly if the car is well maintained - but the plastic chain guides are more problematic.  Unlike belts, all chains are prone to stretch.


I know some people look back on their old Senators with rose tinted glasses, which is nice, but I think everyone would have to agree the Omega has a more refined, more drivable, equal performance engine, certainly handles much better, and is most definately a better ride for cruising :)
Title: Re: timing chain or no t/chain that is the question
Post by: Lizzie_Zoom on 18 April 2009, 11:28:32
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Quote
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......

Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.

So you've said before ........ I ain't convinced.  ;)  ;)
You come across more cars where the rubber bands have snapped than you ever did with chains snapping. I ain't coninced over the stretched chains either ... they sit it their own oil bath.  :y
Generally, the belts don't snap, its normally a bearing that gives up the ghost ;).

Generally, the chains only snap with extreme age - particularly if the car is well maintained - but the plastic chain guides are more problematic.  Unlike belts, all chains are prone to stretch.


I know some people look back on their old Senators with rose tinted glasses, which is nice, but I think everyone would have to agree the Omega has a more refined, more drivable, equal performance engine, certainly handles much better, and is most definately a better ride for cruising :)

Some of us may disagree with that, like my parents and friends in the past!!  When I swapped from the Senator 3.0 CD to the Omega 3.0 Elite they all said how much they prefered riding in the  senny than the miggy!! ::) ::) ::)   It quite put me out at the time!! :'( :'(

However, of course the Omega is a far more advanced car on the Senator, but what would have been really wrong in fitting a chain to their engines??  The cynical part of me believes it was so GM could enjoy far higher profits from after service sales, let alone the odd new engine or so! ::) ::) ::) :D :D ;)
Title: Re: timing chain or no t/chain that is the question
Post by: Marks DTM Calib on 18 April 2009, 12:39:41
I would have a belt over a chain every time.

I much prefer to know where I am with the state of the timing setup.

The chains stretch, the guides wear and they do snap, most are pretty buggered by 100K miles.

The only benefit a chain has is that it does not need changing every 4 years or so.....big deal, it still needs doing every 100K miles idealy and its often a bugger of a job!
Title: Re: timing chain or no t/chain that is the question
Post by: Marks DTM Calib on 18 April 2009, 12:41:34
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Quote
Quote
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......

Because the rubber bands are so much better. The rubber bands don't stretch.  The rubber bands allow Vx to have that silly 20k servicing. And still cheaper to replace 3 times than the chains are to replace once.

So you've said before ........ I ain't convinced.  ;)  ;)
You come across more cars where the rubber bands have snapped than you ever did with chains snapping. I ain't coninced over the stretched chains either ... they sit it their own oil bath.  :y
Generally, the belts don't snap, its normally a bearing that gives up the ghost ;).

Generally, the chains only snap with extreme age - particularly if the car is well maintained - but the plastic chain guides are more problematic.  Unlike belts, all chains are prone to stretch.


I know some people look back on their old Senators with rose tinted glasses, which is nice, but I think everyone would have to agree the Omega has a more refined, more drivable, equal performance engine, certainly handles much better, and is most definately a better ride for cruising :)

Some of us may disagree with that, like my parents and friends in the past!!  When I swapped from the Senator 3.0 CD to the Omega 3.0 Elite they all said how much they prefered riding in the  senny than the miggy!! ::) ::) ::)   It quite put me out at the time!! :'( :'(

However, of course the Omega is a far more advanced car on the Senator, but what would have been really wrong in fitting a chain to their engines??  The cynical part of me believes it was so GM could enjoy far higher profits from after service sales, let alone the odd new engine or so! ::) ::) ::) :D :D ;)

Its easy, a chain setup on a quad cam V engine is a bloody nightmare, all simplex, loads of tensioners, timing issues the lot.

Belts are also quieter.

And GM dont make big profits from aftersales, the garages are the ones that benefit.
Title: Re: timing chain or no t/chain that is the question
Post by: Lizzie_Zoom on 18 April 2009, 13:34:37
Thanks for that TB and Mark! :y :y  

I do now understand what you mean, and I suppose it is just my preference for something made of metal of something of rubber ::) ::) ::)    But of course technology moves on and so do the complexities our all mechanic devices.  These now require a 21st century approach, and not 19th century thinking. 8-) 8-) 8-)  

But I am a steam power girl after all!! ::) ::) :D :D ;)

Title: Re: timing chain or no t/chain that is the question
Post by: Marks DTM Calib on 18 April 2009, 18:16:38
Yes but, the belts are not just rubber, they have a kevlar core (and are bloody hard to cut!)
Title: Re: timing chain or no t/chain that is the question
Post by: kjf7 on 21 April 2009, 23:39:52
well thanks everyone the cars now done 119'000 so do the chains need replacing the old owner (a mate) said the belts were changed but cant find recipt was he stiched up i know he has'nt me as he did'nt want to sell it to me really :y
Title: Re: timing chain or no t/chain that is the question
Post by: CBH on 22 April 2009, 10:07:10
Belts also reduce the rotating masses in the engine and were first used on high performace race engines before getting on to road cars. This enables the engine to change RPM quicker and with less strain on the bearings
Title: Re: timing chain or no t/chain that is the question
Post by: Cybertrucker on 22 April 2009, 10:32:24
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You come across more cars where the rubber bands have snapped than you ever did with chains snapping.
One thing I would recomend, from personal experience, is if you take a belt off for some reason (eg head off) don't put it back on again.  We replaced the camshaft on my Dad's Cortina many years ago (it had developed the classic Pinto engine death-rattle!) and on re-assembly we looked at the cam belt and decided it was okay.  Bad move - it snapped less than a week later, fortunately without causing valves and pistons to fight and killing the engine.

Okay, I'm prepared to accept that belt technology has improved in the last 25 years, but ever since then I've adopted the principle that if I take a belt off it goes in the bin.

Incidentally, although I've not known many belts snapping (apart from that one!) I've seen a lot of belts that have badly worn teeth, to the extent that some teeth are missing completely.  If you get too much of that your belt can jump over one of its sprockets and put your timing out, and in extreme cases it could put your timing so far out that valves and pistons can try to be in the same place at the same time, with disastrous consequences!  :o
Title: Re: timing chain or no t/chain that is the question
Post by: Andy B on 22 April 2009, 10:46:18
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You come across more cars where the rubber bands have snapped than you ever did with chains snapping.
One thing I would recomend, from personal experience, is if you take a belt off for some reason (eg head off) don't put it back on again.  We replaced the camshaft on my Dad's Cortina many years ago (it had developed the classic Pinto engine death-rattle!) and on re-assembly we looked at the cam belt and decided it was okay.  Bad move - it snapped less than a week later, fortunately without causing valves and pistons to fight and killing the engine.

Okay, I'm prepared to accept that belt technology has improved in the last 25 years, but ever since then I've adopted the principle that if I take a belt off it goes in the bin.

Incidentally, although I've not known many belts snapping (apart from that one!) I've seen a lot of belts that have badly worn teeth, to the extent that some teeth are missing completely.  If you get too much of that your belt can jump over one of its sprockets and put your timing out, and in extreme cases it could put your timing so far out that valves and pistons can try to be in the same place at the same time, with disastrous consequences!  :o

I suppose they're better than the Essex engine's fibre gear. It did make them quieter, especially when they stripped their teeth & the engine died!  ;D
Title: Re: timing chain or no t/chain that is the question
Post by: CBH on 22 April 2009, 11:17:34
Essex engine was a great engine a bit heavy but bullit proof.
I used to build and race these and always changed the cam drive gear for a metal one supplied by swaymer racing. On a good 3l road engine you could get 180BHP and on a racing one around 240BHP but I always wanted a Cosworth GAA engine based on an ESSEX block with dual cams per bank, belt driven and was around 500BHP
Title: Re: timing chain or no t/chain that is the question
Post by: Andy B on 22 April 2009, 11:41:41
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Essex engine was a great engine a bit heavy but bullit proof.
I used to build and race these and always changed the cam drive gear for a metal one supplied by swaymer racing. On a good 3l road engine you could get 180BHP and on a racing one around 240BHP but I always wanted a Cosworth GAA engine based on an ESSEX block with dual cams per bank, belt driven and was around 500BHP

Didn't know you could get those kind of bhp's from them,

I wonder if my Dad will let me play with his 2.3 ?   ;D  ;D  ;D
Title: Re: timing chain or no t/chain that is the question
Post by: Marks DTM Calib on 22 April 2009, 11:45:41
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Quote
Essex engine was a great engine a bit heavy but bullit proof.
I used to build and race these and always changed the cam drive gear for a metal one supplied by swaymer racing. On a good 3l road engine you could get 180BHP and on a racing one around 240BHP but I always wanted a Cosworth GAA engine based on an ESSEX block with dual cams per bank, belt driven and was around 500BHP

Didn't know you could get those kind of bhp's from them,

I wonder if my Dad will let me play with his 2.3 ?   ;D  ;D  ;D


You can get those figures from any engine if you throw money at it (i.e. the 500bhp would be expensive).

Trouble with the Essex is that its not a powerful engine out the box and even when tuned up its pretty shite......

30 years ago it could hold its own, in the 80's it was past its best and in the 90's it was anchor fodder!
Title: Re: timing chain or no t/chain that is the question
Post by: Andy B on 22 April 2009, 12:07:03
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......
30 years ago it could hold its own, in the 80's it was past its best and in the 90's it was anchor fodder!

Which is why it's been superceded many times .....  :y
Title: Re: timing chain or no t/chain that is the question
Post by: CBH on 22 April 2009, 12:11:27
You are right we were racing Capris in the 70's
We used Holley carbs on the road engines.
The most expensive part of the race engine was the triple webber setup on the Ford X manfold
The 2.3l and 2.9l were Cologne engines not an Essex these had only two inlet ports per head instead of 3.
The Essex was a cut down Ford V8 that had being designed as a deisel that why it was so heavy
Title: Re: timing chain or no t/chain that is the question
Post by: over50now on 22 April 2009, 23:00:05
My 2006 Astra 1.4 has got a timing chain.   3 days before Christmas, had to have new chain fitted (£450) (Had 44k on the clock). My Mechanic checked with local VX dealer to see if there was a recall.

Had following answer "Nope, but we have just done 8 of those Astras in the past few weeks with 40K on the clock"

Think according to service scheds, 80k should be done.

chain or belt.       or workmanship
Title: Re: timing chain or no t/chain that is the question
Post by: TheBoy on 22 April 2009, 23:02:47
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My 2006 Astra 1.4 has got a timing chain.   3 days before Christmas, had to have new chain fitted (£450) (Had 44k on the clock). My Mechanic checked with local VX dealer to see if there was a recall.

Had following answer "Nope, but we have just done 8 of those Astras in the past few weeks with 40K on the clock"

Think according to service scheds, 80k should be done.

chain or belt.       or workmanship
probably the stupid 20k service interval
Title: Re: timing chain or no t/chain that is the question
Post by: feeutfo on 23 April 2009, 02:21:43
seen an Alpha 147 twin spark with a head full of bent valves. You could see the valve marks in the pistons with spark plugs removed. Belt was still on, just no teeth on it. They where all sat in the bottom of the belt cover. Those engines borderline ,iirc it had done about 500 miles over the recommended belt life. Wrote the car off.
Title: Re: timing chain or no t/chain that is the question
Post by: Kevin Wood on 23 April 2009, 10:09:32
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The 2.3l and 2.9l were Cologne engines not an Essex these had only two inlet ports per head instead of 3.

I remember a couple of test drives when my dad was looking to change his car in the early 90's. 2.9 12v Cologne engined Scorpio (seiously asthmatic) followed by Senator 3.0 24v. Felt like the hand brake had been taken off when we got into the Senator! :o Guess what he bought?

It's interesting how some manufacturers alternate between belt and chain. Ford surprised me with the Zetec-E engines. They engineer a perfectly reliable belt setup that is spec'ed for 100k/10 years (and they very rarely fail within that period). Average Ford owners generally aren't the most dilligent at servicing - so find any weaknesses if they exist.

What do they do? Replace it with a chain driven engine! ::)

The fact is, both will suffer if neglected and both need some maintenance, although the belt change intervals on the GM engines is disproportionately frequent.

Belts are a lot easier to service than chains.

I'd much rather buy a car with a belt, change the belt and know that everything is OK than wonder how dilligent the DPO has been with oil changes on a chain setup.

Kevin