850 head gaskets

No.

Yes. This is a tricky job - there is a special tool that is needed to lift the upper half of the head off. If it's not lifted straight up, then the shoulder at one end will crack off. This same tool is used to push the upper half of the head back down, but at least this is possible with careful tightening of the bolts. Also, there is no gasket between the upper and lower halves, so a special sealant is applied with a roller, similar to a paint roller. If you put too much on, oil passages are blocked. If you use too little, then you get oil leaks. This job is best left to someone who's experienced.

Despite you being an experienced mechanic, the White blocks are not entirely conventional, and indeed considerable skill, care and special tools are needed to R&R the head without causing more expensive problems.

I would either buy a Haynes manual (or other) that details the procedure and borrow / hire the tools, then set aside at least 2 days, or entrust the work to someone who has done it before.

HG failuire on the white blocks is almost unheard of, especially non-turbos and if your car has it, then I would almost guarantee you will find problems when you lift the head including cracks.

These motors as a rule need to be very well cooked to pop the HG through low or crusty coolant, and other parts of the motor will certainly have suffered as a result; be prepared to source a 2nd hand engine complete.

If / when you do the job it is vitally important to replace the water pump, cam belt and all tensioners. I would also recommend you do the cam shaft oil seals too.

Tim..

Pat

If you do this job let us know how you get on.

I can certainly attest to this as I just had my cylinder head replaced because of the inexperience of some previous mechanic. I have a 1995

850GLT (non-turbo) purchased used about a year ago from a dealer who took it on trade. There were a few obvious signs of neglect (no air filter etc.) and the engine seemed to deteriorate very rapidly, detonating like crazy after a few months. Compression test revealed that the #3 cylinder would hold no pressure so a valve was determined to be damaged. Upon removing the CH it was observed that the shoulders around one of the cams were broken off. The previous owner probably took it to an unqualified hack (or tried it himself) and did the damage. Then the engine was hastily reassembled using the same head bolts (except they lost one and used a household bolt) and dumped as a trade-in. They didn't even fix the valve (which was half-missing when the head came off this time).

The net result of all this is that if you do it wrong you have to buy a new CH. In Canada the dealership wants $2695 for the head. Then they sell each gasket separately to the tune of about $400. Dealer wants $10 each for headbolts and you need 12.

I found a used CH for $500 with 42,000km on it but the next best I could find was $1000. The Gasket set came from FCPGroton with a timing belt, water pump gasket, and 12 new head bolts for $180. Had serpentine done then too.

To further support what another poster said, these engines are otherwise very tough... even though the CH was destroyed and the engine ran about 18,000km with a wrecked head, the block was still immaculate and the pistons and cylinder walls showed little wear.

Anyway, my vote is to get someone experienced and then supply your own parts to avoid the Volvo Parts Dept. Gouge-O-Matic and you'll win in the end.

blurp

I don't now, nor hope to ever, need to pull my cyl head, but if something goes awry with it and I stupidly choose to do it myself, where could one get the tool, or is it one that could be easily fabbed?

Ron/Champ 6

1963 8E5 Champ (Champ 6) 1995 VW Passat (Vanilla..yuk) 1994 Volvo 850 (Tilley) 1973 Volvo 1800 ES (Hyacinth Bucket)

A friendly dealer may let you borrow / hire them, but you can make the pull down units from 3 old spark plugs, with the insulators drilled out, and some threaded rod welded in, and a piece of flat bar the appropriate width to span the plug valleys with a hole for the rod and a nut on each to pull the cam carrier down.

Insert the plugs into cyl's 1, 3 and 5, then tighten down abit at a time, evenly.

To remove the cam carrier, again use the tool mentioned above tightened down BEFORE removing the securing bolts, to ensure it lifts up off evenly.

There are some lugs either end of the cam carrier and a copper or similar blunt lever should be used for encouragement, but with *great* care, as the cam carrier must come up evenly on its dowels.

I always use a hide / copper hammer to tap the carrier and persuade it to lift, rather than a lever.

The lugs are easily broken off, and if you are unfortunate they will take part of the casting with them leaving a hole for oil to gush from!

Tim..