crg53

I have an oil leak on the left bank of my engine, thought it was valve cover gaskets, but I am pretty sure its not after trying 4 different times to fix it. First with new gaskets, then with new gaskets and new billet valve covers, then with new gaskets and gasket sealant, and now back to the stock covers with new gaskets, all with the same result.
So my next step is rocker arm seals. My question is, "Can you install the seals with the engine in the car" The bottom ones look pretty easy, but I am unsure about the top ones.
PS. I should add, the stock covers are in VERY good shape, and flat within 0.001"

Metal Guru

You will need to remove the rocker shafts from the cam towers to install the seals. Access to the bottom shafts is easy. Tops will be a little more difficult but I would remove the side engine tins to access the top shafts.
Since you have had your valve covers on a off several times I assume that you verified that you don't have shafts trying to walk out of their bores as this will cause a leak and eventually expensive engine failure.

crg53

Thanks Paul. The shafts are OK as in their location, but I can't think of anywhere else where the oil could be coming from. I also did the gaskets on the oil breather and the oil pressure sending unit even though there was no sign of leakage. The oil drips off the bottom of the valve cover, very much like the picture in Colin's (9M) thread about the red C4 he just bought.

ThomasC2

Are you sure the oil isn't coming from the the rear of the cam housing? A very common leak and when it drips down it "hangs" on the lower edge of the the valve cover.

crg53

That is an other possibility, but that would definitely be an engine out repair. I had a top end rebuild about 20K km ago, it leaked like that before the rebuild as well. When I put my hand up the front of the engine in that area, there is oil in there, was hoping it was rocker arm seals.

PS. The engine only leak when it is running, leaves a few drops on the floor, if I wipe them up after half an hour or so after it's shut down, no more drops.

Metal Guru

You can replace the oil seal & o-ring for the power steering take-off with the engine in the car. I've done it.
I recommend that you clean your engine down really good with brake cleaner, run it and try to pinpoint the leak.

ja78911sc

+1--My Indy did mine with the engine in the car.

crg53

I did my power steering take-off a few years ago, it was leaking badly, but thats on the right side of the engine, my problem is on the left. The right side is now dry as a bone.
Well, I just got in from the garage, the car is up on jack stands ready for me to tear into tomorrow. I was thinking, I have never changed the aluminum washers that are under the nuts for the valve covers, but that wouldn't be cause for the leak or there would be leaks on both sides.

crg53

Went back out to the garage, took off the heat shield, this is what it look like. That engine has not been started for two month and no drips under the car.
It does look like the oil is coming up the studs and leaking past the washers and nuts, but it was the same when I used new gaskets and Curil to seal it off.

Metal Guru

There's a sealing bead that goes around the circumference of every stud in the valve cover. The only way it would leak is if the gasket is damaged.
I think your leak is coming from somewhere else up higher.

crg53

There are no leaks from the top valve cover.
The tin on the front of the engine looks wet, and if you stick your fingers in between the cam tower and the tin, it's wet in there. I think it's leaking from either the rocker shaft or the cam shaft plug at that end, running down and the wind when traveling, blow it back over the valve covers. I will clean it up and run it for a while to see if I can find where it's coming from.

crg53

Update.
I found what I believe to be cylinder #1 exhaust rocker arm oil leak, hard to tell, but definitely from that area. So my question is, if I install the seals, where exactly do they go, do they fit in the groove on the shaft or do they fit on the rocker arm cones ?
Haven't taken anything apart yet or ordered any parts.

Metal Guru

They pop into the groove on either end of the shaft.
Did the rocker arm move?

crg53

I haven't taken it apart yet, so I don't know for sure, will get at it in the next couple of days. Thanks

altonj

If you remove the valve cover it is becomes pretty clear if the shafts are leaking passed their bores. The shaft seals to the bore to prevent oil from coming into the opening where the spark plug is. If this area is dry, shafts are fine....

Pull the cover and post a pic so we can see.

The seals go in the grooves. We use them in every rebuild we do as insurance against not having new cam towers and shafts to ensure a proper seal.

Cheers

Jeff Alton
Turn3 Autosport