Failed Glove test after PCV System replacement Topic is solved

[CouleeBear]

Two weeks ago I had the PCV system on my 1998 V70 AWD replaced by our local Volvo mechanic, and on a whim decided to do the glove check on it again yesterday and it inflated and sprayed a small amount of oil into the glove. I'm wondering if I got a bum replacement or if there could be another reason for the pressure? There's no smoke out of the dipstick.

Also, now that the PCV system has been replaced, I'm wondering how often I should clean the valve? I've heard some say as often as every other oil change.

[beigg]

If they just replaced the box and lines but didn't unclog the potentially stopped up ports, then they minds well just have left it alone.

[Ozark Lee]

Just changing the oil trap and the lines won't completely clear the system. The passage from the oil trap through the sump must also be cleared as well as the PTC valve if the car is a turbo. If the passage from the trap to the sump wasn't cleared out then it will result in excessive pressure and it is a bit tough to get all the crud out of it.

Once other possible cause would be blowby from bad piston rings but that typically also results in excessive smoke from the tailpipe. A compression test is a good test for the condition of the piston rings and the cylinder walls.

...Lee

[erikv11]

Another thing that can cause the glove test to fail is if the hoses are hooked up backwards on top of the oil trap.

There is no PCV valve to clean on these cars, nothing to worry about there. Just get the PTC hole clean as mentioned and check the port into the block.

[polskamafia mjl]

There's no valve on these cars like many american cars use, instead these engines use an entire 'system.'

Its hard to say what the problem is since there are quite a few parts that get replaced when doing the PCV. One of the most important things though seems to be increasing the inner diameter of the hose the runs from the breather box/oil separator to the PTC nipple on the intake pipe near the turbo. Forum member cn90 brought this up some time ago and many people, myself included, have had success with that one simple modification.

To fully resolve the problem it may be in your best interest to simply inspect the components yourself and see if anything is amiss. In addition, if a show performed this work then it seems to me that you should be able to return the car to them and have them correct it if its not working.

Here are two great threads worth reading to become more familiar with what exactly is involved in the PCV replacement:

https://www.matthewsvolvosite.com/forums ... hp?t=28487

https://www.matthewsvolvosite.com/forums ... =1&t=53448

[tryingbe]

I found with the older engines, even with new PCV parts, it is not enough. The stock PCV pipe from the separator to the intake is severely undersized for an older engine. Also, the hole at the heating element at the PTC valve is tiny, like smaller than 1/4 inch tiny. Both will restrict the flow of the crankcase gases.

To address those issues, here is what I do. Get the below parts.

A 3ft 5/8 oil compatible hose. Do not use silicone hose, as it will "sweat" oil. Do not use heatercore hose, it is not rated for oil, it will become soft and you'll have to replace it sooner. This is what I use. Buy 3, as it is sold by the foot.
http://www.ebay.com/itm/291442927889...%3AMEBIDX%3AIT

One 3/4 elbows from your local hardware store. (5/8 will be the wrong size!)

A 3 feet 3/16 inch or 1/4 inch vacuum hose to replace the small hose from the intake manifold to the PTC valve. I prefer silicone hose for this.

Optional, get 6 of this. I like their clamps.
https://www.ipdusa.com/products/4768...4mm-12mm-width

Optional, wireloom to protect the hose.

Take a unibit and drill out the PTC valve holes to as big as you feel comfortable. I think I drilled mine out to about 1/2 inch.

Remove the intake manifold and replace that stock PCV hose, I cut a short hose and then use a 90 degree elbow, than a long hose to the PTC valve. Replace the vacuum hose to the intake manifold to the PTC valve with the new one. Then reinstall the intake manifold.

[rspi]

1. Compression test.
2. Is the ports clean?
3. Did you do the test with the engine cold or warm?

My car has all stock parts, 325,000 miles and tries to suck the glove in.

[erikv11]

Unless you open up the PTC, there is no utility in installing a larger diameter hose.

Rather, the advantage to using generic hose (tryingbe I like how you've done it) is that the parts are cheap and easy to get and install. Whatever you do, make sure you don't end up with a setup where the generic hose is going to fold over on itself and form a closed kink.