964 oil leaks & engine rebuilds ?

[Guest]

Dear All,
My 964 likes to drop loads of oil all over the place, I've removed the exhaust and heat exchangers, cleaned the underside of the engine to see what's going on. It looks like the oil is coming from the joins in the engine, crank case, barrels to crank. What's the cure ? Engine out, strip, etc: Has anyone ever stripped their own engine or is this best left to someone else ? Any ideas of the costs involved ?
Thanks
Peter

 

[tim_haskins]

Hi

It sounds bad I am affriad. I believe that this is an engine out and rebuild time. Likely costs are going to be around 3000-4000 pounds to top end rebuild but if you are leaking from the crank case as well you might be best to have bottom end done as well.You may have to have valves,guides,piston rings etc.It all depends on the engine itself to what work needs to be done. The early engines did not have seals between the barrels and crank case.This will have to be modified to fit the later type seals and thus curing the leaks. I think this job is best left to the experts as unless you know what your doing and have access to machine shop etc it will prove difficult to get right. It will be interesting to hear other peoples opinions let us know how you get on. I would advise you get a independant to look at it before spending this sort of money. Could be worth having clutch/flywheel done at the same time if not done already.

Hope this helps sorry to be the bearer of bad news

Tim

 

[sbloxxy]

I've got a similar problem; my engine also leaks oil - not a huge amount but enough to be irritating. Trouble is, I'm finding it hard to justify spending £3-4k to cure it when I paid less than £10k for the car in the first place. More to the point, even with the engine rebuilt, its still a car thats covered 175000 miles and realistically what will it be worth? Will it be worth the extra £3-£4000 that the rebuild cost me - I doubt it. Its only worth it if I'm going to keep the car for a long, long time and get my moneys worth out of it. I'm afraid I don't know the answer yet - I just keep topping the oil up.

 

[kevin]

Tim,

Early engines did not have head to barrel seals, IIRC they all had barrel to crankcase seals, and htese have chnage colours many times......I might be wrong but I think they are now green.
If you want to knwo the full monty try Rennlist more than a few guys over there have rebuilt their own engines. There's a write up by one of them listed in the Pelican forum, which I must say I tempted to do myself.......the cost was roughly $1200.

Before you go stripping things though, personaly I would ensure its not coming from the top, the oil pressure sender can leak and spread, remembeing that air gets mighty agitated in there, and oil can be sprayed around all over. clean it off well, and then decide, use a compression test, and leakby test to aid your decision, if it's just leaking oil, but the mechanicals are ok, use that to aid your decision.

Kevin

 

[tim_haskins]

kevin,
Got a bit mixed up. You are right about the seals I got it the wrong way around!. It is possible to leak from the top but you would expect to see alot of oil around the top as well as the bottom of the engine. Without seeing the problem it is difficult to diagnose fully. Like you say if the engine is cleaned well then you should be able to see. A leakdown/compression test is only going to show the condition of the top end piston rings/valves etc, Not where the oils comming from obiously. Like kevin says it all depends if the mechanics are all ok then is it worth spending that sort of money. If you valves etc are worn out and you get poor results with leakdown test then it maybe best to either rebuild it yourself if you are competent or get someone to do it for you. Personnally if mine was leaking badly I would seriously consider the rebuild (but mine will never be for sale). There are many things to consider before rebuild I still would get specialist to look at it before making my mind up.


Tim

 

[Guest]

I'm going to clean off as much as possible and have a good look, I'll remove all the ususal junk & tinware to get a better look. I've found that panelwipe is superb at getting oil off the engine, I'll keep you all posted and may even take some pictures and post here. I don't know if I'll get anything done for a week or so as I'm off to Japan for a week, again !
thanks
Peter

 

[Jeff Forsyth]

Peter, don't be too dispondent, as already
inferred, many owners of the early vehicles lived with the leaks. What is the model year of your vehicle ? In 1991 Porsche made model changes as usual and head gaskets were installed after engine serial number 62M06836 (M64/01) or 62M52757 to compensate for the original problem. However, oil leaks may be from a variety of places such as
- seam of cylinder heads to cylinders
-cylinders to crankcase or
from oil return tubes

If there are leaks from the above areas they result in wetness on the lower area of the cylinder head, on the exhaust heat exchangers or on the bottom of the crankcase. Also due to the high op temperatures of carerra 2/4 engines, some blackening of oil at the lower sealing area is possile.This is often considered normal.If the engine is in good condition, i.e. good compression values, low valve seal wear, good power output (can be evaluated by leakdown test etc) then re-builds are not necessary. It would be silly to have a rebuild if it is not needed mechanically, otherwise if you intend to keep it you will probaly have to have the engine out twice over the period of its lifetime. Have it all done at once

Sincerely

Jeff

 

[tim_haskins]

Hi
I do agree that is its worth having all the work done whilst the engine is out for other reasons it will save money and if you can cope with the leaks then thats ok. If you clean the engine and then see excatly where it is comming from then it will give you a better idea. When you say 'my 964 drops oil all over the place' How much are we talking. Still worth having leakdown test to aid dision first they are cheap to have done and at least you will have a good idea to the condition of your engine. How long have you had the car? Did you have PPI done on car before you bought it? What millage have you done since then? Most good PPI would do leakdown test mine did?. How much milage has the car done?

Keep in touch

Tim

 

[Guest]

The engine number is 62L15988, so probably an early engine. I've not cleaned the top of the engine to see what's going on but it's looking better, I've cleaned off the underside and there is a leak from one of the cam chain covers, hopefully (fingers crossed) I'll get away with just changing the cam cover and cam chain cover gaskets. But to cheer myself up I bought a set of 17" cup allows ! If I have to spend some dosh on the car I don't mind so much as it's a RHD car I bought for £9k, on the + side it does not smoke or sound horrible, there was a exhaust blow but I've found it to be from the heat exchanger to head, so I can only guess the exchangers have been off in the past for some reason, hopefully for an engine re-build. Fingers crossed .......