1995 850 NA smoking badly from dipstick tube

[matt122s]

Hi All,
My 1995 850 NA is smoking badly out of the dipstick as soon as you turn it on and I get a puff of smoke out of the tailpipe if I let it idle for 5 to 10 minutes and them floor it. I need your help and advice. I bought it a few months ago on craigslist for $500.00. It had overheated and would not start. It has a mint body and interior so I thought it was worth the asking price. I thought I would get lucky and get away with a head gasket. I had it towed it to a friend who’s a Volvo tech and he worked on it in his spare time. The car had overheated so much that the head was so distorted and not usable. I bought a good used head out of a running car from a salvage yard and had it shaved, cleaned and new valve seals installed at the local machine shop. I also bought a timing kit, water pump, PCV kit, cap/ rotor/ plugs and wires from FCP and all were installed. I picked up the car Saturday and it seems to run well and idles smoothly. It doesn’t overheat, the A/C works great. It drives nicely around town and at highway speeds, cruises at 65 mph and accelerates up to 90mph easily. My mechanic thought it might be a clogged oil pan and dropped it down and cleaned it, he said it lessened the smoking, but it’s still bad. I put a 4’ hose on the dip stick tube and ran it into an empty anti-freeze bottle to catch the oil/smoke. I drove about 50 miles and I have more than a quart of oil in the anti-freeze container. I added a quart of Marvel Mystery Oil to see if that would help clean things out.
At this point I don’t know if the engine was so overheated that it affected the piston rings and I’m getting a lot crankcase pressure caused by blow by. I’m also wondering if the used cylinder head I put was not the correct one. Even though it runs and drives it’s somehow causing pressure to build up in the crankcase, maybe PCV porting is different?
Any help would be greatly appreciated. I don’t want to get rid of the car but I don’t know if I should cut my losses. It smokes so much it’s almost too much to drive, it stinks inside the car. I’m considering buying a used engine and doing a swap in my driveway. I’m fairly mechanical, but don’t want to if I don’t have to.
Thanks, Matt

[MrAl]

Hi,

I have read that smoke from the dipstick could be the PVC system. You can check by putting a glove over the oil filler hole with the cap removed. If it tries to suck the glove in, it's ok, but if it blows the glove up then there is pressure in there caused by a malfunction of the PVC system.

I have read this, and never experienced it, so it may not be that but could be something else that causes unusual pressure inside the engine. I thought i would mention this just in case it is that.

I suppose it could have something to do with the piston rings too, but you'd have to check that out, maybe compression test. If the rings dont seal well enough pressure could get past them, and that would cause it to burn some oil too.

I should tell you though that i dont have that much experience with these engines yet myself, not like the other guys here who could probably tell you more. I just had my car for about a month now and am exploring various topics on repair and maintenance.

[2012]

Make sure the PCV system is installed correctly. Also, bad rings won't cause crank case pressure build up, that's caused by a clog in the PCV system. The bad rings will cause excessive blow by up through the filler cap, which can be checked by the "glove test". This condition is excaserbated by a clogged PCV. Smoking dipstick and excessive oil spitting out means something is not flowing freely in the PCV system. Mines a turbo and has different parts but basically you want to make sure your vacuum lines are free and all lines are hooked up right.

[cn90]

I'd do a "wet" (and dry) compression test.
If the compression numbers improve with the addition of one teaspoon of oil to the cylinder, the rings are badly worn.

[matt122s]

Thank you all for your replies. I'll do a compression test this weekend and post the results as well as take the intake manifold off and check the PCV installation this weekend. I don't think it's the PCV because it's all new components and was installed by a Volvo tech. It's possible that one of the hoses or the box was defective. This guy owns Volvo's and has been repairing them for 20 years. It starts blowing some strong smoke immediately from the dipstick. I've put the glove on the oil filler hole and it fills up quickly. If I put my finger over the dipstick tube the glove fills up even more.
If it were rings wouldn't it show up at the dipstick tube and the oil filler hole? To me it would seem the internal crankcase pressure would be increased at any outlet it could find.

[mika]

the internal crankcase pressure DOES increase in any outlet it can find when clogged. . Looks like you are onto something. Glove should suck in not blow out as you mentioned.

[cn90]

How many miles on the machine?

Being a Volvo tech does not mean he knows ins and outs of every nooks crannies and the idiosyncracies of the PCV system.

jblackburn wrote a DIY for PCV, you should look into it: it is a long thread.
I wrote the 5/8-inch heater hose mod, 2.5 years later, it is still fine.

Back to topic, I have a feeling your rings are worn.

[atucker1]

I had the same problem--new PCV replaced by Volvo shop, but still had smoking dipstick and inflated glove over the filler cap. It's definitely possible the tech didn't clean the PTC Valve. If he did not, there is a tiny little vacuum port on the side. Mine was clogged, and prevented the whole system from working. There are plenty of threads on cleaning the PTC. Try doing that. Totally fixed it for me.

The smoke out of the tail pipe after idling and then gassing it is almost surely the valve stem seals. Those deteriorate and cause oil to be burned in these white block motors.

[erikv11]

This thread is about an NA, which doesn't have a PTC nipple.

[atucker1]

Erik is right. I missed that. The flame trap should be the corresponding part on the NA car and might have not been cleaned.