850 head, valve damage; get used engine or rebuild

vcrush · Post by **vcrush** » 27 Mar 2011, 10:01

I am new to Volvo. A friend's 1997 model 850 quit on the highway. His checkover
suspected engine damage and a high repair cost. He said I could have it, and he
bought another car.
Mileage = 148,000. Location = Texas.
I had it towed to the Volvo dealer for a diagnosis only. I was told the timing belt
had broken and the head was damaged. The estimated repair cost was astronomical.
I said I'd think about it. The service writer then volunteered that if I was going to
sell it, one of their technicians would be interested in buying it.
So I towed it to a general mechanic who does side jobs when he is off work.
After taking off the cover on the left side of the engine, we saw that the timing
belt was not broken, but had popped off as a result of the water pump seizing up.
The belt was slightly frayed on the side for about a 1 inch length.
So the mechanic did a compression check. He said it showed air leakage in
all five cylinders, but especially on cylinders 4 and 5. So the head was removed after
having to soak some of the bolts so they could be taken out. Sure enough, you can
see valves that are not seated, especially around cylinders 4 and 5. On the top
of the pistons in 4 and 5, you can see the little "smile" mark where the top of the
piston banged up top when the belt came off before the parts stopped moving.
The mechanic was concerned that the wrist pin on cylinder number five may also
have suffered damage, although he said when he pressed on the piston, he could
not detect movement in the non-flexing direction; however, the pressure from his
fingers is not the same as that coming from an operating piston.
The twin camshafts are in perfect condition.
So I am faced with--

1. Taking the head to a competent machine shop to be cleaned, checked, and
new valves put in (assuming the head does not have cracks or other physical damage),
and rolling the dice and putting it back on hoping that the number 5 piston will
properly operate and not clatter when the engine runs again.

2. Having the engine rebuilt, which would appear to be an expense greater
than the value of the used car itself.

3. Finding a used engine and having it put in. Getting one that does not have
internal problems of its own would be a dice roll as well.

The car's body and paint are in good shape. I drive a lot and if these cars have
solid suspensions (ball joints not pulling out all the time), and not a lot of road
noise, fixing this one might be worthwhile. I have never even ridden in an 850.
Companies are around that sell used engines, but they vary widely in quality,
I am told, and finding a good used Volvo engine from an engine reseller might
be even trickier.

(I apologize for not knowing what the "trim level" is or how to find it.)

Post by **vjaneczko** » 27 Mar 2011, 13:02

I guess the first question would be; what can you afford?

I'd avoid #1 - but then I don't like rolling the dice.
#2 would be the best option, but as you say, it's $$. If you plan on keeping the car for a while, this may be the best option. 148K miles isn't a lot for these babies - My '97 has over 200K and many others here have over 300K & 400K.
#3 - If you go this route, I'd have a mechanic give it a once-over to make sure it's in good shape before you start the work.

Trim level, paint code and interior codes are all on the aluminum plate mounted by the battery, but if you're lucky and nothing has fallen off the car, you can check the passenger-side trunk for the trim; 850, 850 GLT, 850 T-5 and 850 R.

This will help, too:
http://en.wikipedia.org/wiki/Volvo_850#1997
http://www.volvoclub.org.uk/vin_850.shtml
http://www.erievovo.com/codes.htm#

gilhuly · Post by **gilhuly** » 27 Mar 2011, 19:27

#1 is definitely the way to go. I've never heard of or seen a bottom end being harmed as part of a timing failure. You have some history on the vehicle. People recondition these heads every day and drive these things for another 100k. Timing belt failures are like free money for those mechanics who buy the car from you for 300-500 bucks, do 10 hrs of work on them and sell them for $2500.

Craigd2599 · Post by **Craigd2599** » 27 Mar 2011, 19:33

Clearwater cylinder head co. They will sell you a reman head for $450. Don't even bother remachining yours because it'll cost you more than buying a recon.

Post by **ojdorson** » 28 Mar 2011, 11:40

I'll second the recommendation to just get a re-manufactured head from Clearwater. I did this job myself in the fall and gilhuly's right - the mechanic just wants some free money for what is (for him) a high profit repair/resale.

ed7 · Post by **ed7** » 28 Mar 2011, 16:44

+1 on doing the head. If the crown of the piston isn't severely damaged, go for head repair/replace.
The only damage will show where the piston struck the valve.
Ed

rcannon · Post by **rcannon** » 10 Nov 2013, 18:52

I'm in a similar boat with a burnt valve on a '97 GLT. It uses about 1qt/1k miles and did smoke a bit on start up- bad valve seals. I think the rings are probably about shot but could the valve seals be causing the high oil consumption?

The car is a bit rough- dented hood, door, driver seat worn. Hate to scrap it. I'm thinking of doing the work myself and dropping the pan and doing a ring job as well. Then sell it to someone needing a reliable car but may not even get my money out of it. Or do an engine swap? Or just scrap it? I have another 850, and can use a fender, and take off the good parts and then get ~$250 scrap price for it.

difflock54 · Post by **difflock54** » 10 Nov 2013, 19:43

Were the marks on the pistons actual impact indentations of the valves or the normal factory, cast in 'smileys' as you refer to them?
Was what you refer to as a compression test carried out by your mechanic in fact a 'leak down test' or merely cold readings using a standard compression tester over the spark plug opening and the engine turned over.
What were the readings for each cylinder.
They are commonly 0 for the cylinders which have bent or chipped valves.
Option 1. may still be viable dependant on some of your assumptions.
The state of the PCV system may have accounted for the oil consumption prior to the mishap.
A visual inspection of the PCV trap and the engine block openings for signs of clogging oil sludge may indicate that as an issue readily sorted with the head off the engine.

difflock54 · Post by **difflock54** » 10 Nov 2013, 20:04

See this link attached. Head replacement job.
Several pics of pistons and valve assembly.
The indentations are clearly shown and align with the inlet valves.

https://www.matthewsvolvosite.com/forums ... =1&t=26864

Post by **abscate** » 11 Nov 2013, 05:16

Just to be clear the smilies are NOT damage but are in the pistons when new.