1998 V70 XC - Serious positive crankcase pressure (not PCV)

mindshadow · Post by **mindshadow** » 18 Nov 2010, 10:30

I was driving along yesterday and my car started leaking oil - pretty much all of it came out at once. Oil was under the timing belt cover so it was pretty obvious what it was, but the big surprise was how bad. Turns out the camshaft seal blew straight out of the car. The mechanic replaced the seal, took it for a drive, and it blew the new seal out. His next step was to stick a glove on top of where the oil cap goes and zip tie it on and the glove blew up like a balloon. As the title says, there's some serious crankcase pressure going on.

The PCV job was done several months ago and the car only has 135k miles on it. The mechanic is doing a pressure test on the valves to see if there's a blown piston ring. What the hell besides a blown seal could be causing that much crankcase pressure? And if it is the piston ring what would have caused it to go bad at only 135k miles?

Post by **JRL** » 18 Nov 2010, 13:13

Yoou probably have a line that came off either inside the intake or outside
thus a non working PCV

If you don't see anything it's probably inside

Who did the Breather box work?
What parts were used (OEM or aftermarket)?

mindshadow · Post by **mindshadow** » 18 Nov 2010, 13:28

A line that came off as in part of the PCV system? I do have a kinda rednecked hose that goes back to the PTC nipple; the one that normally goes under the intake manifold. Not sure why they didn't replace that when they did the PCV job.

A local Volvo mechanic with a good reputation did the PCV job. I'm not 100% sure what type of parts they used.

I did a little bit of reading after I posted this and apparently blue smoke when you first start the car in the morning is a sign of a bad valve seal and I do have blue smoke every morning (though it would also be a sign that the PCV is still not working right I suppose).

mindshadow · Post by **mindshadow** » 19 Nov 2010, 13:01

The mechanic said he's going to hang on to it for a while and look at the issue but he's pretty sure it's a piston ring. :\

Post by **cn90** » 19 Nov 2010, 13:12

When all oil comes out at once, it is leaking hose of some sort.
A bad piston ring will cause oil consumption INSIDE the combustion chamber ---> out the tail pipe.

Go to a different mechanic.
Or better yet, check the PCV DIY in this forum, one of your hoses probably comes off. Maybe the hose next to the PCV itself.

mindshadow · Post by **mindshadow** » 19 Nov 2010, 13:15

No, the oil came out because the crankcase pressure blew the camshaft seal right out and then the pressure was forcing the oil out of where the seal was. I exaggerated a tad with "all at once" but it was a very very quick process for it all to come out (probably less than 5 minutes).

Post by **cn90** » 19 Nov 2010, 13:32

Then who did the PCV job and EXACTLY what parts were replaced?

A complete PCV involves all the parts mentioned in this excellent DIY by jablackburn:
https://www.matthewsvolvosite.com/forums ... =1&t=28487

Post by **jblackburn** » 19 Nov 2010, 13:52

A quick compression test will tell you whether or not you have a bad ring - that's all the "testing" he needs to do on it.

Otherwise, I might suspect one of the bottom engine ports is seriously clogged up.

mindshadow · Post by **mindshadow** » 19 Nov 2010, 14:18

Yeah, I think they were doing a compression test but since the car was basically unusable in its current state (and I just straight-up don't have the money to do something that expensive right now) he said he'd tell me something early next week. Since I told him I wasn't in a hurry he went ahead and put a few more urgent cars in front of me.

I'll see if the compression test found anything.