I am having oil pool up on top of the engine of our 97 850 glt, I am trying to locate the pcv valve,but unless thats its on the front I am unable to locate it.Can anyone help me on this,thanks

 

The pcv is on the front of the engine but underneath the intake manifold. It's difficult to see. There are a number of threads on how to replace the pcv. Took me just over 4 hours to do mine for the first time. I also had oil spilling out everywhere.

 

The best way to check the PCV system is to run the car warm then pull the oil dipstick out a little and see if you get smoke out of it. When the system is plugged it will cause pressure to build up in the motor and sometimes causes oil to escape from the oil filler cap and other parts of the engine. Worse case being the rear main oil seal (YIKES).

The PCV is a system not an item. It does have a oil trap box under the intake but that is only 1 component of the entire breather system. I'm somewhat of a slow worker so it took me 7 hours to do our S70 and 6 hours to do my 850.

If you don't see smoke coming out of the dip stick with the engine running, you may simply have a bad oil cap seal.

 

Here's an idea you don't have to follow it, but when your PCV gets clogged and you put oil pressure into the system (hard acceleration) it will squirt out from under the oil cap in a fairly violent manner. if oil has made it up above the engine onto the insulation under the hood, good chance it's too much crankcase pressure from your PCV.

 

Another thing to consider is that the seal on the oil fill cap is bad and oil is leaking out of there. It does not take much to get the oil to pass the seal when the seal is bad. I would replace this first and see if the leaking stops before riping the PCV apart.

 

I pulled the dip stick and the fill cap while it was hot and running and just got very little smoke which would seem normal,but maybe not.I can smell it now while driving getting on the exhaust.I tried to search for a old thtread on PCV and could not find anything,but already my oil is down some on the stick.The seal under the cap looks fine,not brittle or missing pieces.

 

http://tinyurl.com/28rv3cn

 

The PCV system info is in the Sticky Threads, Freq Used Threads: https://volvoforums.com/forum/volvo-850-16/hot-topics-helpful-information-how-diy-repairs-26114/

When checking the PCV system by pulling the oil dip stick out a little you should NOT loosen or remove the oil filler cap.

Again, you could have a bad oil filler cap seal.

 

I am having the smoke forced out of the dipstick tube too. And that's after doing my head gasket (and everything else) job, during which I removed and meticulously cleaned each component of the PCV system thoroughly. I cleaned the oil catch container, all of the lines leading to it, and the flame trap, until nothing else would come out when filled with degreaser. I could blow through it effortlessly afterward, and it air-dried for days in a position to drain out all of the residual water. I used a new intake duct (holes in the old one) that the flame trap attaches to the elbow of, cleaned everything attached to the intake, the hard-line going back to the exhaust manifold, EGR (which was totally gummed up), everything. I even cleaned out the gunk from the three orifices where the PCV container attaches (one up top and two on front) and ran clean diesel fuel through the front two of them (which ran right through and out the drain pan seemingly unrestricted) as part of the engine flushing I did before starting her back up (the top one was cleaned during my head cleaning). I was going to go back with synthetic oil since all of my oil seals are new (with the exception of the rear main) and it only has close to 111,000 miles on it. But if I have continuous pressure like this (which might weaken the rear main) I don't know that I want the high-detergent properties of the synthetic. OR, might the cleaning properties of the synthetic help "open it back up" as far as the PCV system is concerned? Everything else is at 100% and I couldn't be more pleased with the total job I did on this - except for this dipstick pressure still being present. We have put like 50 miles on it since finishing up the job. I am just scratching my head on this one.

Tracy

 

Hi Tracy, slow down a little. I wouldn't worry about it unless you are blowing your dip stick out of the tube. After replacing my PCV system I still had some smoke for about 1,000 miles. Give it some time before you start digging back into things, unless you start blowing your dip stick out.

Take it easy on the motor for about 1,000 miles (easy worm ups, no high rpms, etc.) then double check it. The smoke may just be that things are so new and needs to settle in.

 

Well it is one month later, about 1100 miles later, and I am still having smoke puff out of the dipstick tube if I take it out while the engine is running. I no longer have any accumulation of oil on top of the engine, but I did replace the gasket on the oil filler cap and slightly bend the ears of the cap so they would hold it on tighter. Everything has been cleaned immaculately that deals with the PCV system, and I even cleaned / soaked the ports the oil trap connects to while I had the head off (poured diesel straight through and it would run out the oil drain plug). Any ideas? How concerned about this should I be? Thanks

Tracy

 

Have you done a compression test on the motor?

 

No, I haven't. But since then I talked to a really knowledgeable mechanic friend who owns his own parts store (2nd generation) and he said that a little of that is to be expected with "these Volvos" and assured me it was nothing to worry about. He has never steered me wrong (or been wrong) in my years of buying from him and picking his brain about problems, so I'm not sweating the little bit of puffing out the dipstick tube. YMMV

 

Is there a gasket under the valve cover on top of the engine,mine looks like its coming from that cover.