Hi,
My 1995 N/A 850 has about 275k miles now and has taken to smoking at idle/stoplights, etc. I am thinking about rebuilding the head and fixing the leaking valve stems, i also expect to find a tired/leaking valve or two. the engine really lacks the modest oomph it used to have. Do you recommend rebuilding the head or replacing with a refurb unit... OR...or? or what about a salvage engine with low miles? i have found a few engines with 89~99k miles for $850~975

whaddya think? at this point i think im determined to run this car to a half million miles, most or the suspension has been replaced, the tranny has been replaced with a salvage unit, the AC is working pretty well, but the catalytic is getting full of oil smoke but anyhow...

head rebuild or motor replace, any suggestions? is it a pennywise~pound foolish thing to swap the head at this mileage, but not deal with rings/seal on the block?

thanks for your time
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-woodsy; 275k 1995 850 wagon;

As long as your going to keep the car for 200k more, you should just buy a whole new engine. About 4,600.00 plus installation. That way you can keep driving the car until the seats are just coil springs and no one knows what kind of car it is anymore.

thanks a bunch,
my uncle has said the same, (he'd be the one with the bench for my proposed rebuild) a compression test is next. no point in doing anything else until i know what condition its in.
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-woodsy; 275k 1995 850 wagon;

Do the compression tests first, dry and wet with a warm engine. Someone here mentioned using a drinking straw to add oil to the cylinders: Insert straw into oil bottle to a depth of 2 inches, place finger over top end of straw, move to spark plug hole, remove finger. No mess and 2 inches is about a tablespoon, just perfect.

I would expect compression to be around 150 dry and 175 wet, even though the NA specs are around 200 for a new engine. The rings will wear for at least the first 100K miles.

Removing the head and replacing the stem seals (all 20 of them) is not a lot of fun. Removing the engine is even less fun.
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Keeping it running is better than buying new

ok,
i finally got around to doing a compression check.

DRY RESULTS
1) 170
2) 165
3) 175
4) 165
5) 125...

WET RESULTS
1) 255
2) 245
3) 255
4) 235
5) 185

is #5, leaking valves AND rings?
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-woodsy; 280k 1995 850 wagon;

Probably just a slightly burned valve/seat. The rings are pretty robust in these engines. The 120 reading is low, granted, but filling the rings with oil (looks like you might have used too much) and then having the compression go up is a good thing. A broken ring would have left the compression the same.

If it is just a dirty valve seat, constantly driving at under 2000 rpm is not what these engine require. The valves are designed to spin when the rpm exceeds 2K and the turning motion keeps the valve seats clean and wearing evenly.

A leak down test will tell all, but it is a pain to do. And the results might not be good enough if the valve stem seals are badly worn.

With the head off, a close inspection of the valves is needed. A good machine shop might be needed. But then you need head bolts and a new gasket...
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Keeping it running is better than buying new

ok.
i have often thought that i could hear and/or feel a slight 'lope' or stumble in the engine's rhythm. now i know why, i guess.

i did both dry and wet readings twice with 6~8 spins each and the numbers were within 2~5psi both times for all cylinders. (i think the meter i borrowed from a friend is a harbor freight type and not a proper professional 'TOOL' per-se) my engine gets regular revs above 3k rpm, Virginia highways have long mountain/hill climbs a-plenty.

does the decent compression on the other 4 cylinders explain my avg mileage holding above 20mpg on the highways? does using too much oil do something to the readings? i used a full teaspoons worth of oil in each for the wet reading, i thought that what i read about using, now im second-guessing myself.
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-woodsy; 280k 1995 850 wagon;

A tablespoon of oil is about what you needed in each cylinder. The rise in #5 is equal to the rise in other cylinders, so I suspect that a valve/valve seat is worn and not the rings on #5. It could even be a severely worn valve seal, but that cannot be known unless the head is pulled. And pulling the head almost requires you to refurbish the valves at a reputable machine shop, which is not cheap.

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Keeping it running is better than buying new

10-4
and thanks again, KlausC

the ol' wagon is currently a smoker at traffic lights and i assume this is the valve seals. it smokes warm or cold as it idles, upon takeoff it looks like its running clean. it drinks a quart for every tank of gas in town, but if i'm highway driving it's a quart every 4~5 tanks.

i have an uncle willing to help me rebuild the head, he has a shop where he works on everything from large tractors to cars and lawnmowers. I'm wondering if there is any merit to picking up another head off a salvage lot and re-working that one so i wont have to disable the car for long?

at this point i feel like i'm all-in for better or worse. the last time i looked so closely at something over more than a weekend or two i ended up married! i have seen every bit of this car except inside the block, the ol' black wagon is mine, and i'm hers.
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-woodsy; 280k 1995 850 wagon;

I don't know what salvage yards charge for a head or in what condition it will be in, but that is a possibility. The hard part for P&P yards is removing the exhaust header, the bolts are usually frozen to the block and might snap off.

While things are apart, consider deleting the EGR. A nice intake manifold that comes from a 1996-97 without EGR will be much cleaner.

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Keeping it running is better than buying new

Thanks for the heads up on the exhaust bolts. Not many lots nearby let you 'pull' parts, most like to keep folks out of their lot. There's one local yard that tolerates all my questions and he let me pull a power steering pump and belt tensioner off last year, maybe he'd let me pull a head for cheaper.
And.. Are you telling me I can get rid of the EGR? That would be nice to eliminate! It's the one thing that lights up my dash every week.
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-woodsy; 280k 1995 850 wagon;

I haven't done it yet, it is on my list for 2016. This is a long post:

http://forums.swedespeed.com/showthread.php?229156-95-EGR-delete-success-2-0

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Keeping it running is better than buying new

Tough call.
I recently did the valve seals on my 245K mile '95 854T to fix an oil burning / consumption issue.
It was a challenge, but I got through it.
The suggestion to check the compression of your current engine is a good one.

Overall, I'm glad I did it.
My oil consumption was 700 miles/quart.
I've only gone 2,000 miles since the repair, but so far it hasn't gone down at all.

A couple of comparative compression tests, one with cylinders "dry" and one with oil sprayed into the cylinders, might shed some light on the condition of the piston rings. Once that is determined, it may take a lot of the guess work out of whether you should rebuild the head or scrap the engine.
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Current rides: 2005 Volvo S80 2.5T, 2003 Volvo V70 2.4NA, 1973 Volvo 1800ES (fixed the ignition - now back to the brakes again)