Vijay

Hi there - I've been looking around at the various posts about oil leaks on 993s and it seems like the question of whether to fix a leak or not to fix it has a lot to do with how severe it is and whether you're doing other work anyway.

My mechanic suggested that I fix a leak around my chain cover gasket on my '98 C4S. It's the 2nd time he suggested that I fix (the last time being 1.5 years ago). I'm a bit concerned because I can't really gauge the severity. I haven't noticed any oil stains below the car, but he provided these pictures. The cost of the repair is pretty huge - he says it's about 20hrs of work, which seems a lot higher than people here say it is. But I wanted to run it by people first before I decline to fix it again. The most relevant pictures are below. I'd really appreciate if someone more knowledgeable than me would take a look at them. Thanks!

chaoscreature

If it was my money I would let that one wait until it either gets worse OR you do other repairs on the car to help justify the cost (flywheel, top end job etc).
Just my 2 cents.

Edward

I guess I am having trouble seeing the "cam chain cover" in these pics. I have a seep from my covers and I don't sweat it. It's an engine-out procedure (I've "heard" it can be done with the engine in, but I'll let an expert speak to that). If you're talking Valve-Cover seepate (what I see from your 2nd pic), then yeah, that's easy and typical. But given what I see from your pics (and my own personal acceptance level), I'd wait for an engine-out job, or just wait until it gets worse.

FWIW, my aforementioned cam-chain cover seep has never gotten worse in these 11 years of ownership, so I don't mind the miniscule bit it leaves. But the valve covers did get worse, so I addressed that. Does it leave a drip on the garage floor or a bloody mess?

Edward

Slow Guy

My suspicion is that you're leaking from both the cam cover(s) and the valve covers (both upper and lower). From what little I see in the pics it doesn't look bad enough to do a engine drop (right now). I would save that for clutch replacement time.

However you could do the valve covers now (yourself), they don't require an engine drop.

Vijay

I haven't noticed anything on the floor of the garage. I realized those pictures are from before the valve covers were replaced. He told me they were leaking and it seems like that's a pretty common problem so I had that fixed. I actually brought the car back in because I heard a squeal when I start the car from a cold start and, when turning at low speeds, I hear a growling sound. He says that I need a steering rack rebuild because it's leaking steering fluid and then he brought up the cam cover. The repair is getting pretty pricey and I have to wonder if this is fixable in other ways...

Edward

Clean up the entire area with some dregreaser (and elbow grease ), and re-asses your leak. You should not be leaking from the valve covers if your wrench replaced them (check upper and lower, of course). As for the cam chain cover, I stand by what I said: given what I see in your pics, I'd leave it and wait until you have an engine-out maintenance required (clutch is typical ...be ready with your wallet on that one ...yeaow!!)

BTW, when I replaced my clutch, I had this soaring, mounting list of things to replace "while you're in there" ...no complaints other than the cost, of course. It's clearly cheaper at that time than at any other. And despite all that I had done and addressed beyond the clutch, I FORGOT to mention replacing the cam-chain cover gaskets ...arghhhh!!! So needless to say, mine still seep (duhhh!). So I feel lame, but at least it's a minor seep and still has not ever gotten worse. It's about your own tolerance level

Edward

bobt993

You do have a minor leak on the cam chain cover, but also around the cam chain tensioner which is under a bit of pressure. The tensioner has an oil path that then returns to the valve cover via a small elbow that you see near cyl 1 and 4 valve cover areas (intake). Both are easy repairs. You may want to clean it all up and check for leaking where the cam shroud goes to the block. There is a flat solid gasket that also will leak there. That is a pretty major replacement since the chain, gears,etc need to be pulled to get to it. Clean up the engine real nice and see where your leaks form. Most likely not to worry until you do a top end rebuild.

axl911

It depends on whether the oil makes it way to the heat exchanger and whether you actually use heat on the car or not. If it does and you do, then your heated air will smell like burnt oil. If not, then it doesn't look like it's worth 20 hrs to replace.

TheOtherEric

What leak? Seriously, what leak? Sure there's a wee bit of sludge on the covers but if there's no oil puddling on your heat exchanger or your garage floor, then you don't even have a leak in my book. There aren't even any visible drops of oil where the leaks are supposedly occurring!

Your mechanic is just trying to fill up gaps in his shop schedule. He knows this is silly. And a complete waste of money right now. Just wait until the next major bit of work or until it actually starts leaking.

Vijay

I'm a bit worried about that as well. Maybe he's worried that I won't finish at Le Mans but that small bit of oil isn't the reason

James Hunt

Try replacing the rubber washers/under each of the bolts on the chain cover (s) first. Make sure the ones you have on there are torqued correctly, the torque setting for these is just 9NM. I replaced these on mine (there are 18 in total for both sides) and it has done the trick. Part no for them is 96410514001. This is a link to what they look like and how much they cost. Top left item ........

https://sslrelay.com/type911shop.co....26cid%3D961%26

If your lucky it will sort it for you!

James : - )

NP993

This right here is the correct diagnosis:

Garth S

This is the correct call, IMHO: I replaced the lower ones ~ 4 years ago - and they remain dry: Here's a link to the cup seal R&R, and torque.

I did only the lowest 2-4/side IIRC, as that is where the oil pools - and the heat from the CAT is greatest. The cup washers harden and lose their sealing ability. It is pointless to attempt to tighten them up, as each sits over a metal support pipe ( so while there is a torque spec, it is impossible to over tighten them - OK, one could break the M6 stud)).

Anyway, at < a dollar per washer, have at it with the engine in the car...... very easy DIY!!! If you leave it, I doubt the oil loss would exceed 50 cents/annum vs 20hr engine out bill to save the environment.

IXLR8

Exactly!

In fact, the owner or any shop should degrease and clean the engine before they even open anything up.

Vijay, those valve covers look like $hit and can easily look like this.

Do the upper and lower valve cover seals. Its an easy job.