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850 Valve Job - Start Up Procedure 850

Been doing a valve job on my son's 96 850, non turbo. Burnt valve in #1 cyl.

I have the head back on the car, wrapping up all the bits and pieces. Any suggestions from people that have done a valve job on an 850 regarding start up.

I was thinking of cranking the engine without spark plugs and the fuel pump fuse removed to get oil pressure up into the head and valve tappets all pumped up. Once the oil pressure is up, then inserting spark plugs and fuel pump fuse.

Anyone one who has done a valve job have any suggestions?

Tim








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850 Valve Job - Start Up Procedure 850

All,

Started the car up this weekend and the process of cranking the car without spark plugs and fuel pump fuse out worked very well. I cranked the car well beyond full oil pressure. Turned it off, let the car sit for a minute and repeated the process. When I did put in the spark plugs and the fuel pump fuse the car started after some cranking without any top end noise. Much better than my prior experience with DOHC volvo engines. Much quieter and smoother.

Tim








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850 Valve Job - Start Up Procedure 850

I did one earlier this year. When reassembling the lifters I oiled them heavily as suggested in a book on the Volvo. Your idea of cranking the engine first sure will help get oil into the lifters. When I started daughter-in-laws car it clattered for a very short time and has run well since.

Quite a job, isn't it?

dick








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850 Valve Job - Start Up Procedure 850

Dick,

Thanks for your note. I agree it is quite the job to do a valve job on the 850. I did fashion the tool to hold the cams in place but on the one to pull the top of the head down. Had my son hold the cams and I slowly went around the top cover tightening down each bolt while checking the cam placement.

Did you ever notice when all the crank and cam markings are lined up the #1 cyl is not at top dead center? Odd.

I like the car but the quirks on the 850 sometimes drive me batty. Just getting a new muffler into the car is a pain. Was surprised as his car only had 113K on the clock, my other 2 850s have 144K and 195K and still running well.

Good luck








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850 Valve Job - Start Up Procedure 850

Gentlemen, perhaps you can help me with some info, as both of you appear to know everything about the valve system in the 850.
I have a 1994 850 NA that has started to use a lot of oil all of a sudden, to the tune of a quart every 500 miles. I replaced every thing related to PCV and there was absolutely no change. Before and after the PCV there were noi signs of excessive crankcase pressure.
However, last year I had the cat replaced and when I disconnected the downpipe from the exhaust manifold, I saw that there was some oil in the exhaust manifold. The car has 180k miles on it and runs well. Poer is good and smooth, and there are no funny noises in the engine. No valve clatter at all.

I suspect the valve seals may be bad and in need of replacement. The only circumstances in which I can see a signal of oil burn are in hot starts, when I see a very light puff of smoke out of the tailpipe and when I rev up the engine above 3.2K rpms and bluish smoke comes out of the tailpipe.

I am a little reluctant to have somebody do a valve job as in my country as it is very difficult to find a good mechanic that is familiar with volvos.

My question is related to the valve seals. Do you think it might be the culprit?
Do these seals wear out at this mileage? Can the seals be replaced by just taking out the valve cover, without removing the engine head?

Thanks for your input.

Icelandic








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850 Valve Job - Start Up Procedure 850

The seals are a fairly big job. I think in the US they sell a remanufactured cylinder head, which would make it easier if you can get that.

For me the real question is how long you intend to keep the car and how demanding your future use will be, along with considering the condition of everything else on the car. I suspect in your home country most people keep cars on the road longer than in the US.

My car is in similar but not quite as bad condition with basically the same symptoms. I am not planning on major engine work because I have had lots of good use out of the car, and now the interior is badly worn. Also my car is an automatic, and while I have had zero trouble except PNP switch, some of these gearboxes do fail. I do everything I can to ensure the car is reliable for day to day use. Finally there is the issue of overall energy use, cost and efficiency, where some of the newer cars will do better. So I am prepared not to do heroic work on mine.

Just my own perspective, of course.








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850 Valve Job - Start Up Procedure 850

Tough to call. Could also be rings, especially if the oil was run a long time and rings are filled with carbon. To do valve seals the head needs to come off and that is quite a job. Have you checked the compression? With engine running does the oil cap suck down or does it bobble from blow by?

Check a few more things. Five hundred miles per quart isn't terrible.

Sorry I can't be of more help.

dick








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850 Valve Job - Start Up Procedure 850

With oil filler cap off, there is a slight suction. By the way I am running a Auto RX treatment now (second time in 20k miles). I do not believe I have acarbon build up issue with the rings, however I can“t rule that out. No leaks whatsoever also.








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850 Valve Job - Start Up Procedure 850

If you have a slight suction at the oil filler cap, that is perfect! Which means rings are not bad and letting compression into the crankcase.
If the valve seals are gone, that will not hurt your engine and you may continue to the 200K+ miles just by adding oil every tankful. But that is also the reason why the cat converter went out, too much oil in the exhaust.

With 180K miles, it is a difficult decision because of the cost of repair verses the potential sales price. If the engine runs strong, I would just keep adding oil and I would not use synthetic :)

Klaus
--
Please answer, we need to know if the advice is good or bad. The 164 has a new home, all I am left with are 2 turbos :)







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