Help with Head Gasket

[Misker]

A young friend of mine has just bought an XJ40 with 4 litre engine, 1994 model, he just spent £200 at a garage to get the rear shocks replaced and on his way home noticed white smoke from the exhaust. Well to cut a long story short I reckon the head gaskets gone, you can see liquid on top of no 5 and 6 pistons. The question is will he need to have the head skimmed, or can he just fit a gasket. It seemed the previous owner bypassed the low water level sensor, so there was obviously a problem with water loss. Secondly are any special tools required to do the job.
I said I will help him out, having worked on XK engines and the V12 in the past. He can turn the spanners as I am a bit old for that now.
Thanks in Anticipation.

[melhook]

they are prone to gasket failures, but i would carry a compression check before going any further. I would also consider a cyclinder head overhaul,e.g. lap in valves, new valve stem seals etc. The head can be skimmed, the combustion chamber is in the head, so as long as it hasn't been skimmed too many times before. The heads also suffer from corrosion around the water ways, so a careful inspection is required. You may need to have the head filled and skimmed if the corrosion is bad.
There are no ' special ' tools required, but the following do make it alot easier... camshaft setting tool, dizzy setting tool. Its a fairly straight foward job, just remember that the head bolts are the ' stretch ' type. At Jaguar dealers we were instructed to mark these bolts with a punch on the head if we had removed them, I seem to remember that they can be used 3 times ( ? someone confirm please ?? ). They need to be torqued down, then turned a further 90 degrees.
Hope these helps, please post any other questions.

[Trooper2]

Jaguar head bolts can be used twice.

1st time is at the factory, 2nd time remove and install the head, next time the head comes off buy new head bolts and throw the old ones out.

Edited by Trooper2 on Saturday 26th August 18:54

[Misker]

Thanks guys, I used to use a cam setting tool on the old XK engines, but whats a dizzy tool. I will check the bolts and we have a Haynes manual on the car.
Really greatful.

[Prof Beard]

You can get a very complete Xj40 manual from jaglovers.com - worth a look.

[melhook]

The dizzy setting tool, slides over the top, and ensures its timed correctly. You can do it without it, just make sure you mark it, and put it back in the same place.