yet another PCV question

azureblue · Post by **azureblue** » 08 May 2016, 15:04

I guess about 4 years ago, a shop I trust did a PCV job on my 1994 850T / automatic Volvo. That said, I am losing oil out of an admittedly weak rear main seal. So I did the surgical glove on the oil filler cap test, and found this: Cold car, ambient around 76degrees F. With the glove in place and the first start of the day, the glove inflated and stayed there at idle. I ran the RPMs up to about 2K and the glove stayed inflated for about three seconds, then it deflated. When i let the RPMs return to idle, the glove stayed deflated and it got slightly sucked into the engine. Rising the RPMs again inflated the glove again, but then it deflated again..

What gives? Do I need to do another PCV job on the car? Is something else going out?

Thanks in advance.....

Post by **Ozark Lee** » 08 May 2016, 19:02

Start by making sure the PTC is open. From there, if the PTC is good, then I would pull the elbow from the oil trap to the block and check the passage from the sump up to that elbow.

...Lee

azureblue · Post by **azureblue** » 08 May 2016, 19:14

Thanks - Is it better to clean or replace the PTC valve? There is a junkyard close by....

Post by **polskamafia mjl** » 08 May 2016, 21:23

Cleaning should be sufficient but you can always grab a spare one if you like. Just make sure you clean the spare if you decide to use it.

azureblue · Post by **azureblue** » 09 May 2016, 06:39

Of Course. I usually go to the parts yard and practice a take apart - easy to get a spare. Thanks.

Post by **abscate** » 09 May 2016, 14:02

Its not even a valve, its just a hole. The PTC connector is just a heater connector to help it clean, but there is no mechanical actuator there at all.

The last time someone replaced a hole was in the movie 'Yellow Submarine"

azureblue · Post by **azureblue** » 14 May 2016, 07:07

Just making sure I did the job right - after cleaning the valve I blew through it both ways at ambient temperature and got a little resistance, which I expected. Car seems to come on boost a little smoother. I'll do the glove test today to see if the Crankcase pressure issue changed. Thanks for the help - much appreciated.

Now thinking about putting in a catch can, since I see how easy it is to get to the plumbing.

Post by **rspi** » 14 May 2016, 08:22

The glove test should only be done on a warm engine.

azureblue · Post by **azureblue** » 14 May 2016, 08:52

It was originally run on a warm engine. And I'll do the next glove test, when the car is warm.

BTW the PTC valve was clogged when I first took it off the car to test it..