Excessive Crankcase Pressure 1997 850 GLT Wagon

[Ernesto]

I bought a 1997 850 GLT Wagon a two months ago. So far, it's spent most
of that time at my mechanic's shop. I had to replace the radiator first.
Then I noticed oil was being pushed out of the oil cap. I looked up what
the problem might be right here on this forum, and followed the advice,
right down to ordering parts from Groton.
My mechanic thought the hoses needed changing, since they were brittle
and clogged. He also put in a new oil separator, all new hoses attached to
it, and replaced the manifold gasket. New tune up kit, oil change, and a
cabin air filter, which my car did'nt come with.
He took it for a long test drive and said it runs so much better than before.
It had been missing due to spark plug wire #5 burning a hole through the
insulator, and arcing over to spark plug #4. Even put in a K&N Air Filter!
He told me that it runs so well that he did'nt think the high pressure could
be due to the rings being worn; that it performs great, and the motor was
in good shape and not in need of replacing. Still', he's going to do a leak
down compression test just to be sure. He ran the car and disconnected
one spark plug wire at a time to see if he could get the engine to stop
producing the high pressure.
I read moderator, Made In Japan, who said that there should be a slight
vacuum; that a finger put over the dipsticik hole with the motor running
would feel it being pulled in, not pushed out.
I called my former Volvo mechanic to ask him what he thought could be
causing the oil to run out of the oil cap. He told mt the gasket on it should
be pliable, and should easily bend in half. If it was dry and brittle, that oil
would leak out of it. He also said a slight positive pressure is normal,
which is a distinct contradiction to what I mentioned above. I'm frustrated
Had I known that I would have to spend so much money, be without my
car, not even able to smog it yet, and do all these repairs . . . without a
doubt, I would do it all over again. I'm positively in love with this car.
Five years ago, my Mom gave me her 1988 240 DL sedan. It gave us
great service, logging in 329K when the power steering rack boot tore.
Then I got a 1987 240 DL Wagon, which ran well, but the sedan had more
pep. The sedan had a manual 5-speed, and the wagon was an automatic.
This 850 is so much fun to drive, even though I've had few opportunities
to put her on the road. Even got a cool new set of Michelin Pilot Exalto's.
All of this does me no good since I won't run it with this positive pressure.
I'm afraid I'm going to blow out the rear main seal; other seals & gaskets
Everything I bought from Groton was a genuine Volvo part, with one very
crucial exception. The oil cap I ordered from them was an aftermarket
product, since they did'nt offer the origina; OEM version. It leaks too.
Bought another oil cap from AutoZone, and my mechanic said he did'nt
like the way it rocked back and forth; that it did'nt seem to fit tight enough
Guess I'll head on down to the Volvo dealership today to buy a real one,
but that is'nt going to take away the pressure, which my mechanic was
able to measure. He said it was pushing out a constant 1-2 pounds.
HELP ! Can anyone tell me what else might be causing this problem?
I'm going to ask my mechanic if he checked the bayonette connector
attached to the accordion hose. He did mention that when we received the
oil trap kit with all the hoses, that the only hose not included was the big
accordion hose. I wonder if that connector came with the kit? I don't know
what else we might have missed, but obviously, we did'nt fix the problem.
I'd like your input also on the temporary remedy he suggested we could
do just for now- putting a small hose with a filter on it so that the motor
could vent the pressure out into the atmosphere, thus not taking a chance
on blowing seals,and having the oil continue to come out of the oil cap.
Yes, he did inform me that it would never pass the Smog Test like that.

Thank you all for being here. I'm happy and honored to join this forum.
Please, if you know, what I should tell me mechanic to do next?
We're pulling our hair here. The car has only 90K on it, and the timing
belt was changed at 70K, as recommended by Volvo. I only use premium,
and Castrol Syntec 10-40, which the owner's manual insists on, or the
warranty would not have been valid. Actually 92, 000 miles to be precise.

[mbsl98]

"I'm going to ask my mechanic if he checked the bayonette connector
attached to the accordion hose"
----------------
Do you mean the small fitting down low on the air intake tube from the air box that has two hoses and a small electrical plug? That is about the first place to check when these turbo PVC systems start to block. The small vacuum line that goes into it on the side connects to a passage that may be 1/4 inch or so in inside diameter. However, at the base of that hole is a restrictor that narrows the passage to a tiny hole, just where the passage opens into a much larger passage. That tiny hole clogs easily, and needs to be cleaned out regularly, at least every 30k. I used to pull the whole fitting, but now just pull off the small vacuum hose and insert a pipe-cleaner that is soaked with carb cleaner. Poke it around until you feel it in the tiny hole and keep at it until you can push the cleaner in and out of the hole. Once the pipe cleaner enters the hole, it should still be able to be pushed another 1/2 inch or so. I have seen that some have had it plugged so solidly that they had to remove it and drill out the junk, and it is not that hard to remove, a little harder to get back into its slot in teh air intake hose. If you pull the fitting, also check the hoses that atatch to it for blockage.

[Ernesto]

Hi Mike,

Thanks for your quick reply. I'm pretty sure we're takling about the
very same thing. Here's a photo of what it is right here-
https://www.matthewsvolvosite.com/chat/p ... hp?p=51395
IS this what you're referring to?

Thanks for letting me know this is the first thing to check. Turns out for us,
it might be the last thing to check, since all pertinent parts that causes this
have now been replaced. Much obliged. Best Wishes!

:+)

Ernesto

[Ozark Lee]

Don't buy the oil cap, just buy the rubber gasket. Part number 940096 - even at the stealership it should be under $3.00.

Very slight pressure is OK and it is somewhat normal with high miles.

...Lee

[Ernesto]

In 1997 Volvo came offerd a low pressure turbo on the GLT model.
The levels were Base, GLT, Turbo (or T-5) and the R, a full on racer.
My turbo does'nt have to get to a high rpm or speed to engage. At 1800 rpm the
turbo comes on, with about 9 pounds of boost, compared to the 16-18 or so on
the cars with a Trubo or "R" badge.

Yes, my mechanic was sure to clean out all the fittings, inlets, & connecting points that ran off all of the hoses attached to the oil trap/separator box, the air box,
the turbo, fresh air hose. Everything possible that was mentioned here. I spent a
few night without sleep trying to read through these forums for the answer and at
least that gave us things to try and eliminate from what could be causing this. New oil cap has already been installed. The one from AutoZone
rocked back and forth, but the one from Groton fit well, even though it
was the only aftermarket part I bought from them. Everything else was
genuine Volvo parts, with the exception of the aftermaket, non OEM oil cap
because that is all that they offered.

I contacted an online Answer Service. For $15 dollars, I got the answers from a
man who happens to be the shop foreman of a Volvo garage. Think it's a dealer.
Guy was a real Volvo technician, ASE certified, expert rated, w/12 years of experience
This service gives one the option of not paying if you don't think the answer is
right or are unhappy with it. THis is after you have received your information
I asked my mechanic if I should pay for the answer that was given. He said that
it was good information and of course I should pay for the services rendered.

Here is the answer that the Volvo Technician came up with-
"This may be one to live with, so to speak.. Assuming everything you've stated is correct, and plumbed properly, there should be a slight vacuum. However with an older engine, especially being turbo, if there is enough blowby past the rings it may be enough to overcome the designed crankcase vent system. I do recall one vehicle like this, an 850 turbo none the less. The same scenario was present (new breather box, plumbing, fresh air hose, etc), and still positive pressure remained. A cylinder leakdown test showed the problem.. Worn rings causing just enough blowby to create excessive pressure, even though there was no,or little smoke from the tailpipe as one might expect. A compression, and more imprtantly a leakdown test will likely show some worn cylinders. "

I was'nt happy to hear my rings might be getting worn at only 90K, but I paid.
My mechanic thinks one remedy could be to attach a small hose with some kind
of filter on it and just vent the excess pressure straight into the atmosphere.
Don't like adding to the Earth's polution & global warming but what else can I do?

Thanks to all who took the time to answer and also to all who bothered to read this
Volvo folks are the best. <-------------- Yes! That most definitely is a period there.

:+)

Ernesto
Angeles National Forest
1997 Volvo 850 GLT Wagon
1987 240 DL Wagon- sold to neighbor.
(Glad he's getting good service from her,
but it kills me to see it driven every day,
while my GLT sits at the mechanic's) <g>
1998 240 DL Sedan w/329K-
R.I.P - she went to the crusher unfortunately,
since a new power steering rack costs BIG bucks.