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Omega Help Area => Omega General Help => Topic started by: ScottieMV6 on 30 January 2010, 15:59:41

Title: Head Gasket Change...update!
Post by: ScottieMV6 on 30 January 2010, 15:59:41
Right I am about half way through the head gasket change on my car. All the valves are now out along with all the stem oil seals and I basically have two bare heads.

Questions I have at this point are

Do I need to clean out all the inside of the heads? If so what is the best way to go about this?

When re-fitting the valves how do I lap them in?

How do I fit the manifold studs in at the correct torque? Is there a tool for this?

Sorry for all the questions but i am a head gasket virgin! :y
Title: Re: Head Gasket Change...update!
Post by: Lazydocker on 30 January 2010, 16:23:28
Quote
Right I am about half way through the head gasket change on my car. All the valves are now out along with all the stem oil seals and I basically have two bare heads.

Questions I have at this point are

Do I need to clean out all the inside of the heads? If so what is the best way to go about this?

When re-fitting the valves how do I lap them in?

How do I fit the manifold studs in at the correct torque? Is there a tool for this?

Sorry for all the questions but i am a head gasket virgin! :y

Ideally yes... And I'm told the dishwasher works quite well :-X :-X But probably best to do it when SWMBO isn't about ::) ::) ;D ;D
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 30 January 2010, 16:38:25
Quote
Quote
Right I am about half way through the head gasket change on my car. All the valves are now out along with all the stem oil seals and I basically have two bare heads.

Questions I have at this point are

Do I need to clean out all the inside of the heads? If so what is the best way to go about this?

When re-fitting the valves how do I lap them in?

How do I fit the manifold studs in at the correct torque? Is there a tool for this?

Sorry for all the questions but i am a head gasket virgin! :y

Ideally yes... And I'm told the dishwasher works quite well :-X :-X But probably best to do it when SWMBO isn't about ::) ::) ;D ;D

Seriously???? With normal dishwasher powder/tablets??? :o

Anyone help with the other questions?
Title: Re: Head Gasket Change...update!
Post by: Andy B on 30 January 2010, 17:40:43
Quote
......
When re-fitting the valves how do I lap them in?
 ......

One of these (http://cgi.ebay.co.uk/Universal-Valve-Grinding-Stick-Tool_W0QQitemZ260544863760QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item3ca9af1e10) and a tub of grinding paste  ;) & grind back & forth till you have an even continuous ground band on the valve seat.
People use a drill on the stem, but I've never done it that way  :-/
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 30 January 2010, 17:55:13
Quote
Quote
......
When re-fitting the valves how do I lap them in?
 ......

One of these (http://cgi.ebay.co.uk/Universal-Valve-Grinding-Stick-Tool_W0QQitemZ260544863760QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item3ca9af1e10)[/url] and a tub of grinding paste  ;) & grind back & forth till you have an even continuous ground band on the valve seat.
People use a drill on the stem, but I've never done it that way  :-/

Ordered, thanks Andy.

So heads in the dishwasher, grinding stick and paste. Someone just tell me how to get the studs torqued up and I will leave you alone for a bit! ;D ;D
Title: Re: Head Gasket Change...update!
Post by: Entwood on 30 January 2010, 17:56:59
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Quote
......
When re-fitting the valves how do I lap them in?
 ......

One of these (http://cgi.ebay.co.uk/Universal-Valve-Grinding-Stick-Tool_W0QQitemZ260544863760QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item3ca9af1e10) and a tub of grinding paste  ;) & grind back & forth till you have an even continuous ground band on the valve seat.
People use a drill on the stem, but I've never done it that way  :-/


IMHO that does NOT give a decent face... as all the motion is in one direction. The grinding tool between the palms, rubbed back and forth, then lifted, rotated 90 degrees, and continue... is the way I was taught..  :)

I know .. daft old sod .. but it works ..  :)
Title: Re: Head Gasket Change...update!
Post by: Andy B on 30 January 2010, 17:59:43
Quote
....
IMHO that does NOT give a decent face... as all the motion is in one direction. The grinding tool between the palms, rubbed back and forth, then lifted, rotated 90 degrees, and continue... is the way I was taught..  :)

I know .. daft old sod .. but it works ..  :)

Agreed! A squirt of WD40 helps too  :y  :y
 I must be a daft sod too.
Title: Re: Head Gasket Change...update!
Post by: Lazydocker on 30 January 2010, 17:59:56
Quote
Quote
Quote
......
When re-fitting the valves how do I lap them in?
 ......

One of these (http://cgi.ebay.co.uk/Universal-Valve-Grinding-Stick-Tool_W0QQitemZ260544863760QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item3ca9af1e10) and a tub of grinding paste  ;) & grind back & forth till you have an even continuous ground band on the valve seat.
People use a drill on the stem, but I've never done it that way  :-/


IMHO that does NOT give a decent face... as all the motion is in one direction. The grinding tool between the palms, rubbed back and forth, then lifted, rotated 90 degrees, and continue... is the way I was taught..  :)

I know .. daft old sod .. but it works ..  :)

I have done it both ways in the past (with mini/metro heads) and must confess I think that they are better lapped by hand :y :y
Title: Re: Head Gasket Change...update!
Post by: Bent valve on 30 January 2010, 18:21:30
Personally, I wouldnt clean the heads until the valves have been ground. be extra carefull not to get any paste(only use the fine not the coarse grade unless the seats are really pitted which is unlikely nowadays)  anywhere other than on the valve seat, if it gets into the guides it will bugger them up very quickly.

If you soak the heads in a solution of biological washing powder and warm water for a few hours you can then hose the crud off  :y
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 30 January 2010, 18:50:54
Right so lap the valves before cleaning the heads. Clean the heads in the dishwasher or using the washing powder/hose method. Then I assume it needs to dry (if done in the dishwasher assume the dishwasher will do most of that?
Title: Re: Head Gasket Change...update!
Post by: rodney on 30 January 2010, 20:04:47
dishwasher? pmsl ,

jet wash the heads off so you can blast all the shit from in em ,

the manifold studs aint hard , if you cant put a small socket or e tourqe , then lock 2 nuts together on the stud , then put it in and tighten up with a spanner,.
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 30 January 2010, 21:49:51
Have I been taken in by a little joke here? Should the heads go in the dishwasher? ::)

Someone give me a serious answer :y :P
Title: Re: Head Gasket Change...update!
Post by: Entwood on 30 January 2010, 21:52:37
Never put heads in a dishwasher .. but have put many other engine parts in, while SWTSMBO is at work of course..  :)

The high temperature and strong detergent ensures that grease and other gunge is removed very easily .. :)

I see no reason why heads can't go in .... temps are well below that of the cylinders. IMHO
Title: Re: Head Gasket Change...update!
Post by: djac on 30 January 2010, 21:58:36
Lapping 24 valves by hand? Sounds like hard work.

I've got one of these http://www.avenue35.co.uk/shopping/shopexd.asp?id=37739

It's the best of both worlds, converts the rotary motion of the drill into an oscillating action just like a lapping stick - only faster ;)

If you were closer you could borrow mine......
Title: Re: Head Gasket Change...update!
Post by: Entwood on 30 January 2010, 22:01:48
Useful bit of kit ... but quite expensive for one use .. :( 
Title: Re: Head Gasket Change...update!
Post by: Lazydocker on 30 January 2010, 22:04:12
Quote
Have I been taken in by a little joke here? Should the heads go in the dishwasher? ::)

Someone give me a serious answer :y :P

Nope.. I was deadly serious :y :y

Of course... The other suggestions are all feasible too ;) ;)
Title: Re: Head Gasket Change...update!
Post by: djac on 30 January 2010, 22:05:12
Quote
Useful bit of kit ... but quite expensive for one use .. :( 

although it might seem quite a bargain when you get to the 12th valve! ;D
Title: Re: Head Gasket Change...update!
Post by: Entwood on 30 January 2010, 22:07:57
Quote
Quote
Useful bit of kit ... but quite expensive for one use .. :( 

although it might seem quite a bargain when you get to the 12th valve! ;D


Very true ..... Last time I used one of the manual lappers was on an MGB engine ...  only 8 valves to do .. :)
Title: Re: Head Gasket Change...update!
Post by: ChevetteNick on 30 January 2010, 22:31:19
I used to lap valves for a living and would only recommend doing them by hand and using the course paste. You're looking at it taking a good 10mins per valve, that was with reground valves and seats, if you want a good job being done.
I personally wouldn't use the dishwasher purely on health grounds :o
If the ports are full of moist gunk then wipe them dry first, the inlets should be ok as the petrol cleans them before entering the combustion chamber, and use petrol with an old toothbrush to clean them up before jet washing them.
Title: Re: Head Gasket Change...update!
Post by: Elite Pete on 31 January 2010, 09:16:10
I would use Nitromors to clean the heads Scottie :y
Title: Re: Head Gasket Change...update!
Post by: Jimbob on 31 January 2010, 09:18:54
Im sure mine have been through a dishwasher  :y
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 31 January 2010, 10:46:51
Thanks for all the help guys. I'll crack on with that today then! :y
Title: Re: Head Gasket Change...update!
Post by: dbug on 31 January 2010, 16:11:35
Quote
Quote
Quote
Quote
......
When re-fitting the valves how do I lap them in?
 ......

One of these (http://cgi.ebay.co.uk/Universal-Valve-Grinding-Stick-Tool_W0QQitemZ260544863760QQcmdZViewItemQQptZUK_Hand_Tools_Equipment?hash=item3ca9af1e10) and a tub of grinding paste  ;) & grind back & forth till you have an even continuous ground band on the valve seat.
People use a drill on the stem, but I've never done it that way  :-/


IMHO that does NOT give a decent face... as all the motion is in one direction. The grinding tool between the palms, rubbed back and forth, then lifted, rotated 90 degrees, and continue... is the way I was taught..  :)

I know .. daft old sod .. but it works ..  :)

I have done it both ways in the past (with mini/metro heads) and must confess I think that they are better lapped by hand :y :y

Use of drill on valve stems good if valves/sets badly pitted.  Best to do final lapping by hand.  Used that method years ago on Cooper S's when I used to race them.
Title: Re: Head Gasket Change...update!
Post by: Andy B on 31 January 2010, 21:46:58
Quote
.....
Use of drill on valve stems good if valves/sets badly pitted.  Best to do final lapping by hand.  Used that method years ago on Cooper S's when I used to race them.

On the last head I did, the few valves that were badly pitted I took to a local engine place & had them reground on the machine. A couple of quid each IIRC  :y  :y
Title: Re: Head Gasket Change...update!
Post by: MarkG on 01 February 2010, 09:05:14
I put my FJ1200 cylinder head and barrels in the dishwasher at max temp when the Mrs was out a couple of months ago. She came home half way through the cycle and went absolutely ballistic. When it had finished, there was flash rusting all over the barrels and white alloy furring all over. Took quite a while to clean off. Also I had to run the dishwasher empty on max temp for 3 cycles to get rid of the smell. I would not do it that way again. 
Title: Re: Head Gasket Change...update!
Post by: Kevin Wood on 01 February 2010, 11:02:18
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I put my FJ1200 cylinder head and barrels in the dishwasher at max temp when the Mrs was out a couple of months ago. She came home half way through the cycle and went absolutely ballistic. When it had finished, there was flash rusting all over the barrels and white alloy furring all over. Took quite a while to clean off. Also I had to run the dishwasher empty on max temp for 3 cycles to get rid of the smell. I would not do it that way again. 

Ahh. You used dishwasher powder in it, not Jizer, didn't you?  ;)

Kevin
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 01 February 2010, 11:11:51
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Quote
I put my FJ1200 cylinder head and barrels in the dishwasher at max temp when the Mrs was out a couple of months ago. She came home half way through the cycle and went absolutely ballistic. When it had finished, there was flash rusting all over the barrels and white alloy furring all over. Took quite a while to clean off. Also I had to run the dishwasher empty on max temp for 3 cycles to get rid of the smell. I would not do it that way again. 

Ahh. You used dishwasher powder in it, not Jizer, didn't you?  ;)

Kevin

What is Jizer Kevin?
Title: Re: Head Gasket Change...update!
Post by: Kevin Wood on 01 February 2010, 11:15:41
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What is Jizer Kevin?

http://www.amazon.co.uk/Swarfega-Jizer-Litre-Degreaser-Jiz609/dp/B0001P0UAE

 :y

Probably not the best stuff to do the dishes in, on reflection.  ;)

Kevin
Title: Re: Head Gasket Change...update!
Post by: dbug on 01 February 2010, 11:16:21
JIzer is an emulsifiable Degreasing Fluid.  Widely used in industry and the automotive trade.  Rinses off with water.  ;)
Title: Re: Head Gasket Change...update!
Post by: MarkG on 01 February 2010, 13:16:22
Correct. I used a dishwasher tablet. If I was doing it again, I'd soak it in de-greaser and then power wash it. I would not put it in the dishwasher.
Title: Re: Head Gasket Change...update!
Post by: MarkG on 06 February 2010, 11:42:39
So ScottieMV6....what did you use and how did you get on?
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 06 February 2010, 12:43:13
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So ScottieMV6....what did you use and how did you get on?

Not used anything yet. Been removing all the crap etc off the faces using scotchpad etc.

Don't think I am going to use the dishwasher though TBH. Think I will soak them in degreaser and then powerwash :y

Gonna do all that on Monday though as its my birthday tomorrow so having a night away tonight :y
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 09 February 2010, 09:40:00
Degreased and powerwashed the heads yesterday and they are now a lot cleaner than they were.

Might sound like a daft question but do they have to be bone dry before re-assembly?
Title: Re: Head Gasket Change...update!
Post by: Kevin Wood on 09 February 2010, 10:32:20
Quote
Degreased and powerwashed the heads yesterday and they are now a lot cleaner than they were.

Might sound like a daft question but do they have to be bone dry before re-assembly?

I would blow an airline or similar through the oil galleries to dry them and blast out any crud that might have been washed into them. Apart from that a little dampness won't do any harm.

Kevin
Title: Re: Head Gasket Change...update!
Post by: Marks DTM Calib on 09 February 2010, 10:45:35
Make sure the threaded holes are clear.....you dont want a bolt/stud to hydraulic on insertion.
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 09 February 2010, 13:22:54
Ok thanks.

Is there anything in particular I should know when re-assembling?

Mark - James mentioned you had done a follower servicing guide but I can't find it. Can you let me know how to go about it?
Title: Re: Head Gasket Change...update!
Post by: Marks DTM Calib on 09 February 2010, 13:33:18
Where your followers noisey?
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 09 February 2010, 13:52:27
Not that I know of!
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 10 February 2010, 12:45:44
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Where your followers noisey?

I assume then if they were not noisy they don't need servicing?
Title: Re: Head Gasket Change...update!
Post by: Marks DTM Calib on 10 February 2010, 12:51:13
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Quote
Where your followers noisey?

I assume then if they were not noisy they don't need servicing?

Yep
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 10 February 2010, 12:52:36
Thank you....off to start re-assembly now! :y
Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 12 February 2010, 15:14:42
One head completely re-assembled, other one just needs exhaust manifold etc. re-attaching.

Have to say that 20NM on the exhaust manifold nuts seems a bit light but I am doing everything by the book!

Is putting the heads back on the car a 2 man job or can I do it myself?  :y
Title: Re: Head Gasket Change...update!
Post by: Marks DTM Calib on 12 February 2010, 15:49:51
I have done it myself a fair few times!

I also do the manifold nuts to 25Nm.....ensuring the studs are in the head before the nuts are fitted.

Title: Re: Head Gasket Change...update!
Post by: ScottieMV6 on 12 February 2010, 16:02:38
Ok - I'll nip them up another 5 NM tomorrow just to be sure. I did put the studs in the head first :y
Title: Re: Head Gasket Change...update!
Post by: Andy H on 12 February 2010, 16:59:56
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Quote
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Where your followers noisey?

I assume then if they were not noisy they don't need servicing?

Yep
I would at least squeeze the oil out first.

If the valves have been reseated then the followers need to be compressed otherwise they will remember the previous learned valve clearances (which won't match the reseated valves) and might result in no compression.
Title: Re: Head Gasket Change...update!
Post by: Marks DTM Calib on 12 February 2010, 17:01:48
Quote
Quote
Quote
Quote
Where your followers noisey?

I assume then if they were not noisy they don't need servicing?

Yep
I would at least squeeze the oil out first.

If the valves have been reseated then the followers need to be compressed otherwise they will remember the previous learned valve clearances (which won't match the reseated valves) and might result in no compression.


They will be fine......on these hardened seats, you cant take owt off them and within a few turns of the cam, they will have leake down enough  :y
Title: Re: Head Gasket Change...update!
Post by: Andy H on 12 February 2010, 17:26:45
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Quote
Quote
Quote
Quote
Where your followers noisey?

I assume then if they were not noisy they don't need servicing?

Yep
I would at least squeeze the oil out first.

If the valves have been reseated then the followers need to be compressed otherwise they will remember the previous learned valve clearances (which won't match the reseated valves) and might result in no compression.


They will be fine......on these hardened seats, you cant take owt off them and within a few turns of the cam, they will have leaked down enough  :y
That's good to know :y