Cam cover gasket replacement

My '88 V12 needs the bank B cam cover gasket. It is leaking oil in the exhaust manifold and causing a smudge cloud that causes fire department equipment to follow me around town. I am assuming that the injectors and intake manifold must be removed prior to get to the cover. Are there any other pitfalls that are lurking in this job? And is there a gasket set available to do the job, or do I order the gaskets individually and hope that I get it right the first time?

Intake manifold, fuel rail, and injectors all come off as one piece. Easy peazy.

And has been discussed numerous times: Assembled with OEM gasket and half moon seal, it will leak sooner or later. To avoid a leak for a decade or more, use the genuine Jaguar rubber half moon seal (aftermarket parts use inferior rubber that dries out and cracks sooner) and use no gasket at all, just seal the joint with Loctite 518. It will seal until the rubber half moon expires, which may depend on how hot the engine runs.

To avoid a leak for a lifetime, buy a set of aluminum half moon seals – somebody on here was recently offering sets for sale. Assemble with the aluminum half moon and with a gortex sandwich gasket (gortex/metal/gortex) which you’ve got to insist upon or someone will sell you a paper gasket.

In either case, you will probably need to replace the cam cover screws; the originals probably have triangular threads, and those should be discarded. Ideally, buy a box of 6mm alloy socket head screws about 5-10 mm longer than the originals. Install with a split ring lock washer and a flat washer under the head of each screw. Make very sure that the OD of your flat washer is small enough to sit flat in the recess in the cam cover.

Another option is a set of hex head screws 15-20 mm longer than original, and install with a 10 mm spacer and a split ring lock washer under each head. This puts the heads up high where they’re easier to get at to retighten.

1 Like

Here’s the thread on the aluminum half moons:

Oh, I almost forgot: You might want to confirm that it’s actually your cam covers that are leaking. Another common leak path is the joint between the tappet block and the head, which doesn’t have a gasket. Per the ROM it’s supposed to be sealed with Hylomar, which is a lousy choice for such a location; a good steam cleaning can cause a leak. To stem this leak, it would be necessary to remove the tappet block and seal it up properly with a bead of Loctite 518.

Also, the parts don’t actually mate up too well, there are places where the machined surface of one piece lands over a void in the other. In the worst case scenario, the joint might not leak except that oil might leak up the studs to the domed nuts holding the cam cover on. Those nuts originally came with copper washers under them, perhaps to attempt to stem such leaks.

In the Book there’s a diagram of where the bead of Loctite 518 should be applied to seal that tappet block to the head. Contrary to popular notion, simply gooping copious amounts of the stuff anywhere and everywhere is not recommended.

Unfortunately, resealing the tappet block requires removing the cams, which in turn involves fiddling with the timing chain tensioner. Read up on that job before heading down that path.

There’s a write-up on the project at my webpage:

Also while you’re in there: You’ll want to remove each of the 3/8" head nuts along the outboard edge of the head, one by one, and replace the flat washer under it with a flat washer that’s 1/8" thick. Reinstall each nut and torque to spec before moving on to the next nut.

Any thought on intake gaskets. It appears that they are available as a single gasket for one bank, or six gaskets, one per inlet. Additionally, the only ones I have found are made of paper. I know Jaguar used paper for a long time, I just didn’t know it was in the 21 century.

Yeah, the latest intake gaskets are thick cardboard and 2-piece. They work fine, although most recommend a gasket dressing such as Hylomar or that black Toyota stuff.

Note that, when installed on a pre-H.E., they reportedly make it a bit harder to get at the spark plugs. And on any engine the connections between ports remain visible. Some opt to cut the 2 pieces into 4 pieces or even 12 pieces prior to installation. It’s easy enough to position one against an intake manifold and mark where to cut it into pieces.

And remember to retorque the intake manifold nuts after the first time the car gets warmed up and then periodically after that.

In addition to Ed,s website you might also want to look at a link from 20 years or so when I replaced the cam end seals.