850 head gaskets

Hi Folks...

I'm a professional truck mechanic and, consequently, have done all the
repair and maintenance on my '87 240 wagon since new. It appears that
my wife's '93 850GLT has developed a head gasket leak. Unlike the 240
which I do in an afternoon with a couple of beers this one appears
slightly more complicated.

Questions: Is this engine more prone to cylinder head problems like
warping, cracking, etc. that would increase the cost beyond rational?
Are there any hidden gizmos requiring special tools not ordinarily
found in a reasonably complete tool box? Mitchell gives me about 9 hrs
for the job, is that reasonable?

Regards

Pat Hayes

 

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.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

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.

ttfn......Alistair

 

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..