1995 850 non-Turbo pcv problem

rred · Post by **rred** » 29 Apr 2018, 13:22

My car is a 1995 volvo 850 non-Turbo with about 175k miles on it. I've been driving it for about 10 years and like it.

Long story short. I found engine oil came out from the engine cap and also noticed white smoke from the dipstick. After searching the forums, I think it's the clogged pcv. I left the car to a local mechanic shop to check what needs to do. They replaced the oil trap box and suggested an engine flush when next oil change is due. This is about three weeks ago. The problem is I still see engine oil comes out and white smoke from the dipstick. I also did the glove test yesterday and got a standing glove with some engine oil inside.

My question is
1, will an engine flush solve the problem?
2, should I replace all the pcv system beside the trap box? (Probably I'll do it myself.)
3, any other problems to check, assuming the pcv is already fixed?

PS. Seems they were in a rush when working on the car. When I went to pick up the car at the end of the day, they haven't finished it. Later I found they forgot to put the fuel rail cover back and left a washcloth under the hood. They also broke one connector to the battery, which they fixed and charged me $3 for the part. This is why I'm considering to do it by myself if I need to replace the whole pcv this time.

Thanks a lot for reading and any suggestion is appreciated.

Post by **FlyingVolvo** » 29 Apr 2018, 13:45

All they replaced was the oil trap box? That's usually the one part you can re-use because it rarely gets fully filled/clogged as far as I know. Where it connects to the engine block IS a place that needs to be cleaned out though.

: PICT6541.JPG (162.4 KiB) Viewed 2216 times

I'm not as familiar with 850 models, but assuming they're relatively same in design, the other big clog point is where the hose from the oil trap goes into the air intake through the PTC nipple.

: PTC Valve.JPG (68.17 KiB) Viewed 2216 times

I think your car also has a flame trap somewhere in there that's prone to clogging, but you'll need to ask an 850 guy about that.

Post by **misha** » 29 Apr 2018, 14:15

Ptc is a TURBO item only...n/a don't have it.

Post by **abscate** » 29 Apr 2018, 14:16

The PTC cleaning is a 50000 miles maintenance item on a new car, it’s probably prudent to clean it at twice that interval 20 years later

Post by **FlyingVolvo** » 29 Apr 2018, 14:19

misha wrote: ↑29 Apr 2018, 14:15 Ptc is a TURBO item only...n/a don't have it.

Thanks for the clarification.

rred · Post by **rred** » 29 Apr 2018, 15:03

ecbsykes wrote: ↑29 Apr 2018, 13:45 All they replaced was the oil trap box? That's usually the one part you can re-use because it rarely gets fully filled/clogged as far as I know. Where it connects to the engine block IS a place that needs to be cleaned out though.

Yes, I think they just replaced the box. That's what they told me through the phone and what appeared on the receipt. If they replaced anything else, I think they will charge me for it. They also showed me the old box, which is definitely clogged. Not sure whether any cleaning is done or not.

Post by **Rattnalle** » 29 Apr 2018, 15:07

If the box was clogged the pipes into the block most certainly are too. Other pipes may be as well.

rred · Post by **rred** » 29 Apr 2018, 22:06

Rattnalle wrote: ↑29 Apr 2018, 15:07 If the box was clogged the pipes into the block most certainly are too. Other pipes may be as well.

I don't know whether the box is fully clogged. But they showed me the input and/or the output are clogged. So this means I need to replace the pipes? I have read through several posts on the forum. Looks not like a very easy project. (The most difficult one I've done is replacing the cooling fan.) Guess I will start with figuring out the parts I need.

Post by **Rattnalle** » 30 Apr 2018, 00:24

It's a bit of work since you need to remove the intake manifold but not rocket science.

Post by **erikv11** » 30 Apr 2018, 09:01

rred wrote: ↑29 Apr 2018, 22:06
Rattnalle wrote: ↑29 Apr 2018, 15:07 If the box was clogged the pipes into the block most certainly are too. Other pipes may be as well.
I don't know whether the box is fully clogged. But they showed me the input and/or the output are clogged. So this means I need to replace the pipes? I have read through several posts on the forum. Looks not like a very easy project. (The most difficult one I've done is replacing the cooling fan.) Guess I will start with figuring out the parts I need.

If the box is clogged, then PCV service is badly needed. Replace all the PCV hoses, find and throw away the flame trap (probably also clogged up), and most definitely inspect and clean out the passages from the engine block to the box.

For the three smaller hoses that connect to the box, you must buy Volvo branded parts. Many people have done this aftermarket PCV hose experiment: if you buy aftermarket, you must go back in 2 years or less replacing rotten hoses. For the long hose/pipe that connects to the oil trap, you can either DIY and buy your own hose (find the method posted on this site by tryingbe, the hose he uses is definitely the best choice; second best is a pre-bent 90 degree heater hose) which will save you about $50, or the other option is you must buy the Volvo branded pipe.

PCV isn't hard but it takes a long time to take everything off, then put everything back on. Don't forget you also need an intake manifold gasket to do the PCV job. I would replace all rubber vacuum hoses while you are in there (viewtopic.php?t=65002). It is a pesky job but the 20 year old rubber hoses under the hood are mostly falling apart by now.

Also don't take your Volvo to that shop again, they don't know how to work on it.