I have been making lots of forward progress with my 87 XJ6, and this past Friday it seems as if the head gasket let go. Symptoms:
going 70 mph, suddenly engine seemed less responsive
temp and oil pressure looked good
pulling off freeway could smell something burning slightly
as I slowed smoke from under hood
parked, opened hood, oil pushing past valve cover gasket on left rear side, dripping onto exhaust manifold cover, plus going past crush washer on acorn nut
coolant reservoir was empty
let engine cool, had to move it to edge of gas station lot I was in, tough to start
engine sounded like old VW, lots of white smoke
smoke continued to come out of left side tailpipe for about 4 minutes after engine shut off

So, time to drain the engine, see what the fluids look like, and begin the removal of the head process. Lots of penetrant will be used on the studs. I was hoping to not worry about doing the head gasket until after the new year. No such luck.

 

Hi MIke

Is this a very late XJ Series 3 with a 4.2 litre engine, or an early XJ40-type XJ6 with a 3.6 litre (and all alloy as well) ?

 

It's a very late Series 3 with the 4.2 engine.

 

I feel for you....read through my "need someone smarter than me" thread. Lots of info to be gleaned regarding head gasket issues. I had the same symptoms.

 

I've done head gaskets on E Types and my XK140 when I had it, but that was at least 16 years ago. I'll be buying bulk amounts of penetrant/loosener to really soak the studs. This will also be a time to fix the weepy water pump housing and replace all hoses and belts.

 

Even the change to slotted blocks in 1980/81 didn't cure the tendency to blow head gaskets on these engines when they had done a few miles.

How many miles on the car ?

Fortunately you seem to have caught it in time, although only when you get the head off will you know. Look carefully at the metal between the bores and make sure there is no cratering from combustion gas burning. If there is, you might need to face off the block or in a bad case, fit lipped liners. These late blocks have no liners.

 

Crateriing between cylinders. Oh, yeah, bad memories. But, worked out OK!!

In the mid sixties, I commuted from SOCAL's AF valley to the mid Wilshire part of LA. My freeway intimidator was a well worn 57 Ford short bed pickup. A Q ship as it was powered by a quite healthy Tbird V8.

Well, it blew a gasket between cylinders. I delayed the fix as I was really busy on more than one front.

When, I finaly pulled the heads, oh, oh, cratering between two cylinder bores!!!

Why it blew the gasket in the first place was an unsolved mystery.

So, I reverted to an old machinist dodge/bodge. I used a sharp punch to make little pimples in the low. That raised the surrounding metal. I filed the "fix" flat with the rest of the surface. Could've added a liquid weld or sealant, but didn't.

While at it, the heads got the valves lapped and skimmed.

Put it back together and it ran better than ever. I sold it some time later, doing quite well. it's new owner did some needed body work and added a paint jopb. Nice truck til it got rear ended by a bigger truck and hard !!!

I came close to buying it back to fix. But, realized I did not have the time and probably not the equipment to pull the frame!!!!

Carl

 

It has about 100k miles on it, give or take. The speedo stopped working late last year just before I bought it. (I verified it by the mileage on the last oil change receipt.) I'll drain it this weekend and see what fluids have ended up where.