Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

Input please re my oil leak

decgraham

Well-known member
Joined
17 Sep 2008
Messages
1,664
OK last year I changed all the suspect gaskets on the car, camshaft covers, cam chain, cam tensioner and oil bridge O rings but still had a small leak. It was suggested by Gaurds Red that it might be a "Through bolt" and I should try a thicker oil. I did this and to be honest it hasn't got better but worse. Now my question is :-

The oil that drips is golden in colour not dirty or contaminated in any way. It looks like it did when I put it in after the oil and filter change last October. However, when I look down on top of the engine at the back where there are a few pipes I can see some dirty oil on the pipes. I am thinking could the pressure relief valve from the oil tank be spewing oil out? and if so does it go to the LHS of the engine via a pipe? I'm thinking of taking off the inlet manifold so I can have a good look and see if this is the case and I have a leaking pipe. What has made me think this, is today, I kept having to start the car to move up the line at the ITV station about 9 times in all. At the end of the ITV the guy took me down in the pit under the car and showed me the oil on the cross bar and the cover, a lot more then would usually be there. Again though the oil was golden and clean. Could I have an over pressure issue from the oil tank ??

Any input greatly appreciated :thumb:

ATB :)
 
Not that I'm an expert on these things, well apart from the fact that all my seals leak !

When you did upper cam cover gaskets did you change the covers as well as the gaskets ?

On mine that I bought recently it had new gaskets last year ( before my ownership) and a combination of warped gaskets and then the bolts being torqued too high means we are about to do them all over again !

Probably not the same issue but just a thought

Phib
 
I did a reseal this winter all the usuals but I did notice a leak from the cam chain housing. Didn't fancy doing it myself so left it for the moment excellent write up :-
https://rennlist.com/forums/964-for...aks-cam-housing-to-case-camshaft-o-rings.html
The oil tank pressure relive valve just vents to atmosphere via a U-shaped hose at the top of the tank.
Dirty oil mist at the back of the engine is most likely flapper valve seals, the vram one is notorious for leaking.
 
phib said:
Not that I'm an expert on these things, well apart from the fact that all my seals leak !

When you did upper cam cover gaskets did you change the covers as well as the gaskets ?

On mine that I bought recently it had new gaskets last year ( before my ownership) and a combination of warped gaskets and then the bolts being torqued too high means we are about to do them all over again !

Probably not the same issue but just a thought

Phib

Thanks for the reply Phib but I checked my covers with a straight edge and they were as flat as a pancake :lol: When I changed the gaskets I replaced all the bolts as well. I was well pleased with the work but then.... still a small leak :evil:

ATB :)
 
Endoman said:
I did a reseal this winter all the usuals but I did notice a leak from the cam chain housing. Didn't fancy doing it myself so left it for the moment excellent write up :-
https://rennlist.com/forums/964-for...aks-cam-housing-to-case-camshaft-o-rings.html
The oil tank pressure relive valve just vents to atmosphere via a U-shaped hose at the top of the tank.
Dirty oil mist at the back of the engine is most likely flapper valve seals, the vram one is notorious for leaking.

Hi Endoman,

Had a look at the write up, very good indeed but I don't think I'm quite up to the job :oops: do a fair bit of spannering but when special tools are involved I leave to the specialists.

I know you just fitted a VR to your Non VR car so you'll know your way around the top of the engine. Mine is Non VR too. The dirty oil mist pipes are just behind alternator cowling. Is there anything else there that could leak oil? My RHS is as dry as a bone. Thanks for the info re the oil tank. Does it make any difference that mine is a Tip ?

ATB :)
 
Hi Endoman,

I've just had a good look in the PET and I see on page 34 it shows all the oil pipes. I notice there are a couple of breather pipes which have jointing pieces, do you think one of these could have come loose?

ATB :)
 
If there is a leak at those larger breather pipe you would probably hear a whistle when the engine is running as they are subject to -ve pressure. The pic shows the underside of my non vram manifold when it took off, just a cheap liitle o-ring but it had left quite a mess over the engine cowel.
it's not difficult to remove manifold just a bit time consuming and don't drop anything down the inlet throats. Makes changeing the plug leads a doddle.
The inlet manifold will probably be covered internally with quite an oil slick as mine was.
I took the manifold off before I dropped the engine just intending to short out that leak and one from the crankcase breather elbow. Then a Vram came up on Rennlist. I'd been looking for a couple of years so I jumped at it. The tricky bit was then locating a suitable ecu. Found the right one new in Germany, that stung a bit.
 

Attachments

  • resonance_flap_seal_185.jpg
    resonance_flap_seal_185.jpg
    95.6 KB · Views: 3,490
Thanks for the feed back Endoman :thumb:

I think I'm kidding myself and just hoping that it might be something simple like a leaking pipe. Got under the car this morning and the leak is what it was. I think yesterday at the ITV there must have been a build up of oil on the under tray and when they did the brake test on the rolling road it must have spewed out.

You can see in the pics attached where it's coming from by the red arrows. It's small and after the engine is up to running temperature it stops, then drips again once the engine has cooled until it stops dripping which takes a few minutes.

I think if I want a completely leak free engine I'm going to have to bite the bullet and have a re-seal done by a professional. It's such a shame after all the work I did last year and the car runs like a dream. Oh well Que sera sera.

ATB :)
 

Attachments

  • leak_1_712.jpg
    leak_1_712.jpg
    218.4 KB · Views: 3,414
  • leak_4_146.jpg
    leak_4_146.jpg
    138.3 KB · Views: 3,414
decgraham said:
I think if I want a completely leak free engine I'm going to have to bite the bullet and have a re-seal done by a professional. It's such a shame after all the work I did last year and the car runs like a dream. Oh well Que sera sera.

I know how you feel.....
I've had my cam covers re-done twice over the years, and still I have a leak. Not a lot, but bloody annoying when it leaves a drop on the floor :frustrated:

I've now got mine booked in for a top end rebuild at 9m over winter. It's the only way ...... :nooo:
 
AndyS said:
decgraham said:
I think if I want a completely leak free engine I'm going to have to bite the bullet and have a re-seal done by a professional. It's such a shame after all the work I did last year and the car runs like a dream. Oh well Que sera sera.

I know how you feel.....
I've had my cam covers re-done twice over the years, and still I have a leak. Not a lot, but bloody annoying when it leaves a drop on the floor :frustrated:

I've now got mine booked in for a top end rebuild at 9m over winter. It's the only way ...... :nooo:

Thanks Andy,

Yes it is upsetting, all the areas I covered with new gaskets are fine just that small leak you can see in the pic.

Out of interest what sort of money have you been quoted for a top end rebuild if you don't mind me asking?

ATB :)
 
decgraham said:
Thanks Andy,

Yes it is upsetting, all the areas I covered with new gaskets are fine just that small leak you can see in the pic.

Out of interest what sort of money have you been quoted for a top end rebuild if you don't mind me asking?

Not at all - I'm using 9m, so may be paying slightly more than other places. I just want to know it's right and they have a good rep.
It's price-book, and shown on the web site. They quote £1950 + vat for labour, then you have to factor in removal and refitting of the engine and the cost of all parts including gaskets and consumables. Ball park figure estimate is around £5500 all in - unless something horrible is found.....
 
Thanks Andy much appreciated. There are a couple of specialist I know of in Alicante and Valencia so it gives me a good idea when it comes to negotiating the price :thumb:

ATB :)
 
Hi decgraham,

The arrows on your picture point pretty much exactly where the through bolts for the case halves are having come through the block from the other side. I'm afraid that chances are it will be them.

To check, it is possible to remove the air guide that covers the bolts though it is a bit of a pain. To do so, both oil return pipes on that side have to come out (one of yours looks like it has a dent, though they look orginal - not the extendable ones). Then the studs holding the air guide in place need to come out, these can be unscrewed using two bolts. Thre are three studs. Finally the main oil return pipe screwed into the base of the block has to be disconnected. If the through bolts are wet the seals have failed.

Unfortunately the through bolts go through the main oil galleries and are under pressure via the oil pump, as the oil thins as it gets hot it will leak past the seals.

This can happen on older engines when well intentioned owners change the oil to modern synthetics with cleaning agents. This oil removes the crud built up on the inside of the seals and they leak.

There is no fix other than disassembly to the point of taking the case halves apart.

What oil are you using?

Regards
GR
 
Thanks GR your knowledge is second to none IMHO :worship: you told me this last year. It's just that I had a brain storm, yes I know can be dangerous :lol: and thought it just might be something else. Don't think I'll be doing all that you suggest, with respect I'll pass it onto a professional and get them to sort it. You don't fancy a few weeks in Spain do you 8)

Oh the through tube got the dent when I removed the coupling and replaced the aluminium washer seal ring, just in case the leak was thete. Didn't keep my eye on the spanner. :frustrated:

Oil is now 15/40 as you suggested.

Thanks again for your input

ATB :)
 
I'd love a week in the sun, but I'm still carrying my "winter" fat and nobody needs to see that in a teeshirt...

Best of luck with it.

Regards
GR
 

New Threads

Forum statistics

Threads
124,354
Messages
1,439,458
Members
48,711
Latest member
Silage
Back
Top