Replacing rocker cover gasket...

[Sandspider]

Hi all

Further investigation of my mystery oil leak shows that it seems to be coming from the back of the rocker cover (just in front of the firewall) and dripping down the block rather than coming from the crankcase seal. Good news, as it's easier to work on the top of the engine and I shouldn't need to drop out the clutch, transmission etc.

But, I had a look on the Clarks garage website and through all the workshop manuals and on here, and I couldn't find much info on rocker cover removal. I thought it would be fairly simple, but looking at the engine the fuel rail and some other bits and bobs are in the way (and possibly the timing belt covers too) and there seem to be rather a lot of bolts knocking around, including some that must hold the cylinder head on. I don't want to take those ones off! Do the fuel rail, distributor cap, timing belt covers etc. all need to come off to free the rocker cover?

Would anyone be able to point me to some form of instructions as to how to remove the rocker cover without dismantling more of the engine than necessary?

Many thanks.

 

[will lyons]

Hi you've found yourself an intresting little job yes the distibutor needs to come off and beneath the sump plugs you will find the remaining bolts holding the cambox in place as you will find it is not a cover but actually part of the cam containing the relevent lifters etc. I had a specialist replace mine earlier this year. As the pressure in the engine is circa 6bar if it isn't done and the gasket fails you will Find high pressure oil spraying from the leaking area. good luck with it's replacement.

 

[sulzeruk]

Giles, you may find it is the cork gasket at the back of the head is leaking, a very common problem. Try seeing iof that is the culprit first rather than the actual cambox,
Alasdair

 

[Sandspider]

Thanks chaps. I'll have another wrestle in daylight!

Alisdair, I can't really tell, it's too hard to see down the back of the block. Best I can tell is it's coming from a corner at the back right hand size of the block (if facing forwards), about 2 inches down from the top. I think it's where the cambox joins the block. How could I tell if this is the cork seal or the rocker cover seal? :s Also, is the cork gasket harder or easier to fix than the rocker cover gasket?

Cheers,

Giles

 

[sulzeruk]

The cork gasket is held on with 3 10mm headed bolts and takes 5 minutes to change. The cambox takes a good 2 to3 hours as you need to get the timing belt off and then re-time the engine. My money would be on the cork gasket!
If you feel down the back of the cambox (right at the back if standing at the front of the car), you should be able to feel the oil at the bottom. It quite often runs off and drops down onto the exhaust manifold where it joins the mid section.
Alasdair

 

[Sandspider]

Well, fingers crossed it's the cork one then!

Yes, I can feel oil down the back of the cambox where you say. (I think it's coming from the bottom of the cambox where it joins the block). It runs right down the back of the block and drips off the edge of the sump where it joins the front of the crankcase, hence I thought it was a leak from the crankcase seal.

Hmm. I can find the rocker cover gasket on Eurocarparts and Bert Gear has it, but no mention of a cork seal... Does it have another name?

Thanks for your help with this. I thought it would be a simple matter of whipping out a few bolts, taking off the rocker cover, replacing the gasket and bolting it all back up again!

 

[sulzeruk]

My laptop with PET on it has dies so can't get you the part number! Phone Bert up and ask for the gasket. It is held on with 3 6mm threaded bolts. It mounts the back engine lifting eye on as well. He should know which one it is. I get them from the OPC for about £2 I think.
Alasdair

 

[JM1962]

The cork gasket is 928.105.189.02 and Berlyn services have it for the princely sum of £1.18 including the taxmans share.

 

[Fat Albert]

Just had mine done, ended up having a new belt and water pump at the same time, so it cost me about £500, annoying as I only had the belts done last year, but was unhappy removing and re-tensioning an existing belt

 

[Sandspider]

ORIGINAL: JM1962

The cork gasket is 928.105.189.02 and Berlyn services have it for the princely sum of £1.18 including the taxmans share.

Ah hah! Thanks Jim, it's just listed as "gasket", so you've saved me some time there!

And thanks again Alisdair, I'm off shopping

Jeremy, I know what you mean - I'm prepared to have a go at most things on the car myself, but getting the timing belt set up wrong is just too much of a risk... (And knowing my luck, possibly too likely!)

 

[chrisg]

Giles

having taken the 944 turbo engine apart on a number of occasions my comments and thoughts:

1. The 944 engine unlike other engines doesn't actually have a camcover gasket (compared to my BMW engine) where you can actually get at/touch the cam - it has a sealed cam box in which runs the cam on bearings which for the majority of DIY engine builders/ maintainers doesn't need attention.

2. IIRC the gasket between the head and the cambox isn't cork (unlike a mini cam cover....) but a 'proper' gasket. Over time, because of the engine being tilted, the exhaust side of this gasket will start to leak because of the oil drain effect.

3. Is it definitely this gasket that is leaking ? I know there's a cork gasket at the back of the engine where the rear cambearing (with the engine lifting loop/ clutch hose is) is ?

4. To replace the cam gasket involves: A. Removing the rotor cap and the outer cam sprocket cover (aluminium)

B. Removing all of the housing for the belts and the belts so as to be able to free the cam sprocket. - Make sure you have the engine at TDC before you do this - see Clarks for how to do this - BTW remove the plugs to turn the engine over without compression.

C. The various bolts (total of 8 I think) that hold the cam box on - dry external ones above the exhaust, wet internal ones that are accessed through the removal ali sealing bolts (BTW you need a long 6mm hex drive for these).

D. ISTR it's easier with inlet manifold removed but not essential

E. Untie/ remove anything bolted to the rear of the camtower e.g. clutch pipe

F. When you do remove the cam tower - be careful not to drop any of the cam followers onto the exhaust as you remove it.

Last but not least, unless you have the skill/knowledge to refit the camtower and time up the belts correcly with the right tension - pay a professional to do it

 

[Sandspider]

Thanks Chris for the detailed write up.

I imagine (hope) that the Lux engine is a bit simpler than the turbo, but even so- I'll replace the cork gasket at the back of the block myself and hope that does the trick. If it's not that, I'll pass it on to someone who knows what he's doing. (As I said, I prefer to leave the timing belts and major engine dismantlement alone). I'm due a belt change in the next year or so, so could get the rocker cover / cam box gasket replaced then if necessary. It's still better / cheaper than having to get someone to drop the whole transmission to replace a crank case seal!

Cheers.

 

[chrisg]

Giles

Ref. clutch seal, hell yes, tell me about it.....

With regard to the Turbo vs Normally aspirated engine - I've no doubt some of the purists will argue but:

Based on my limited observations (not having owned or tinkered with a 2.5 or 2.7 944) the engines and ancillaries are pretty similar, albeit there's a lot more pipework with the turbo = very simplistic comment I know but it's all relative compared to the S or S2 !

 

[Sandspider]

8 valves is (complicated) enough for me!

 

[Sandspider]

Well, I've replaced the cork gasket, for the princely sum of 54 of her majesty's finest pence! The old one didn't look too bad when I took it off, but the bolts holding it on weren't done up too tightly. I couldn't really tell where the oil leak started, but I've got a spare cam box gasket too. Fingers crossed the other gasket won't be needed, and thanks for all the help [8D]