Gents:

Still having some difficulty starighteneing tout the new Jag (2000 XK8). The drivers side valve cover is leaking at the rear corner. New gaskets and have had it off twice (added a little silicone). It seems to be leaking over the gasket (between valve cover-gasket) or almost appears that the valve cover is porous?! Any advice/experience/tips/tricks on this?

Also, had the lean codes 121 reappear after fixing several leaks so still chasing that.

I may need a replacement valve cover, and I do need a coil cover. I also may need an upper intake plenum. If you recall my earlier post there was a hairline crack at one of the bolt holes that was repaired with JBWeld. I have not had it re-smoketested yet.

Anyone have a good source for these parts? (I checked eBay and only found a coil cover).

Thanks!

Tom

 

As for the valve cover leaking after installing a new gasket I would ask if you torque the blots. If you did then your cover surface is not level and may need to be replaced. If you are saying you have a code P0121 giving you restrictive performance you need to read my post on the TB plug TBoddy this is not uncommon for your year car and the TSB will explain. Hope this helps!

 

Thanks Gus,

My main issue is the lean codes at this point. The oil leak is secondary.

We fixed a couple of vacuum leaks at the load breather, the intake, and the TB, but the lean codes returned (bank 1 only for now).

I wantto get the oil leak fixed then put a few more miles on it too see if it will trip add'l codes.

Tom

 

Think about it if your valve cover is leaking it would be the same as the breather stub hose leaking. Fix the leak and also check the gas cap. Yes the gas cap, I recently received an e-mail telling me of this fix. I hope this helps!

 

When you did the cam cover gaskets did you replace ALL of them? Meaning the big gasket, and the spark plug O rings, and all of the little seals around the bolts?

 

Andy,

Yes, the leak is at the rear edge of the cam cover. With a light and a miorror it seems like it is leaking over the hasket. like between the gasket and the cover itself. It's hard to see but it almoist seems like it is weeping throught he plasitc cover itself.

Tom

 

I have a small leak on the right front corner. My mechanic said that's pretty typical. If new gaskets were installed and you're still getting the leak, you'll need a new valve cover. And I'm not 100%, but I guess you're not supposed to torque them down or you'll warp them.

 

..overtorque is worse

 

I have a 2000 XK8 convertible with 46K miles. The valve cover seals have been replaced on my car at least 4 times that I know of. All the seals were OEM parts, and they always seem to fail. When the seals fail, I get an oil burning smell and you can see smoke (burning oil) coming out of the right or left side of the hood. Most recently, the left and right side valve cover seals failed within 1,000 miles of being replaced.

I have checked the valve covers, and the heads, and they do not seem to be warped. I always torque the seals down properly using the proper specs. And the dealer has even attempted to fix this problem the first 2 times without any success. I do not know what is causing the seals to fail so often. Does anyone have any suggestions as to why the seals are failing, or how to fix this problem? Someone suggested using silicone to seal the seals and valve covers. Any thoughts?

Thanks.

 

The seals are probably not the problem. Look to the valve covers. Only takes one time to overtorque the bolts and they do not heal themselves.

 

When I had my XK8 one of the cam covers was cracked.

I bought a new drivers side cam cover from Jaguar parts center, and a set of gaskets for the other cover.

The new cover came with all gaskets and wasn't terribly more expensive than the gaskets alone.

I guess what I am saying is buying new covers to be sure is cheaper than a couple of sets of gaskets, and the time changing them.