Crankcase pressure question

0151rhys · Jan 6th, 2016, 21:03

Okay I replaced the pcv system and the car runs well. However I decided to do the glove test and placed it tight over the filler cap. It sucked in slightly at idle and when I reved it high it inflated very and I mean very slightly and very quickly and very quickly returning to the same amount of vacuum it was at idle. Is this normal or should I be checking something else now as a result.

CNGBiFuel · Jan 6th, 2016, 21:08

The PCV system si the weak link with this engine, caused by the hoses themselves, and not using fully-synth oils. Remeber Volvo have yet to make a car or hose for you.
See:

http://www.matthewsvolvosite.com/for...ic.php?t=53448

Keep an eye on it, if it settles to -ve as you describe it will be OK.

The permanent fix... and it's the only way, is to now throw the lot away and repalce with £15 of heater hose. If you're going to do real miles or keep it, you'll be forced to in the end.

colwyn · Jan 7th, 2016, 11:37

I wouldnt hake heater hose as gospel, I tried that on my first car to try and relocate the crank breather then the pipe just dissolved into a black mess

rudi dudi · Jan 7th, 2016, 12:52

You could just ignore it!!

Lots of nonsense around here regarding this Pcv .

I've got one on 270k owned from new and has been like that from the factory.

960kg · Jan 7th, 2016, 13:19

As above ^^^^^ Very true ...utter tosh all the hype.

DaveNP · Jan 7th, 2016, 14:07

Given that we're talking about the PCV system which handles hot oil vapours definitely not heater hose, if you want a bigger hose get something resistant to oil and petrol vapours, heater hose will be degraded by the oil vapour and could end up totally blocked.

Brianjone5 · Jan 9th, 2016, 09:54

As I understand it, the glove test is performed at idle. Momentary pressure as you raise the revs is not important.

colwyn · Jan 9th, 2016, 18:02

I think it's vacuum at idle and as it under load it equalises to atmospheric pressure

bournricha · Jan 9th, 2016, 19:58

IT is perfectly fine ,there will be momentary pressure on speeding the engine .The vacuum afterwards shows the pcv is sucking out the fumes as it should .Main thing is you have not got smoke puffing out of the dipstick hole .

960kg · Jan 10th, 2016, 12:18

At idle it is supposed to be + 2or3 kilopascal....not even .5psi.....but definitely on the plus.

Jan 6th, 2016, 21:03	#1
0151rhys New Member Last Online: Jan 10th, 2016 21:35 Join Date: Nov 2015 Location: Wirral	Crankcase pressure question Okay I replaced the pcv system and the car runs well. However I decided to do the glove test and placed it tight over the filler cap. It sucked in slightly at idle and when I reved it high it inflated very and I mean very slightly and very quickly and very quickly returning to the same amount of vacuum it was at idle. Is this normal or should I be checking something else now as a result.

Jan 6th, 2016, 21:08	#2
CNGBiFuel Classic P80 1999 BiFuel Last Online: Mar 6th, 2024 00:34 Join Date: Aug 2012 Location: 48mph Middle Lane M4	The PCV system si the weak link with this engine, caused by the hoses themselves, and not using fully-synth oils. Remeber Volvo have yet to make a car or hose for you. See: http://www.matthewsvolvosite.com/for...ic.php?t=53448 Keep an eye on it, if it settles to -ve as you describe it will be OK. The permanent fix... and it's the only way, is to now throw the lot away and repalce with £15 of heater hose. If you're going to do real miles or keep it, you'll be forced to in the end. __________________ Bifuel V70 Classic 1999 [The Old Grumpy in the Corner, "When I was a lad... blah, bl*dy blah."] Last edited by CNGBiFuel; Jan 6th, 2016 at 22:04.*

Jan 7th, 2016, 11:37	#3
colwyn Resident Ejit Last Online: Feb 19th, 2024 09:05 Join Date: Dec 2014 Location: Skelmersdale	I wouldnt hake heater hose as gospel, I tried that on my first car to try and relocate the crank breather then the pipe just dissolved into a black mess __________________ 96' 855 GLT auto 2.5 10v in dark olive pearl 97' Omega GLS auto 2.0 16v in oyster ABS controller problems, give me a shout

Jan 7th, 2016, 13:19	#5
960kg Premier Member Last Online: Dec 28th, 2022 12:25 Join Date: Jun 2009 Location: Mercville	As above ^^^^^ Very true ...utter tosh all the hype. __________________ Mercedes C320CDI Sport Estate 3 litre V6 7 Gear Auto Remap 290bhp 628Nm torque @ 1600revs 45.1mpg Last edited by 960kg; Jan 7th, 2016 at 13:22.

Jan 7th, 2016, 14:07	#6
DaveNP Non VOC Member Last Online: Today 07:17 Join Date: Jun 2011 Location: Milton Keynes	Given that we're talking about the PCV system which handles hot oil vapours definitely not heater hose, if you want a bigger hose get something resistant to oil and petrol vapours, heater hose will be degraded by the oil vapour and could end up totally blocked. __________________ David V70 2.5 10v Torslanda Manual 98 Sreg

Jan 7th, 2016, 12:52	#4
rudi dudi DPF free.FCUK Greta he he Last Online: Mar 28th, 2024 13:38 Join Date: Jun 2012 Location: Bristol	You could just ignore it!! Lots of nonsense around here regarding this Pcv . I've got one on 270k owned from new and has been like that from the factory.

Jan 9th, 2016, 09:54	#7
Brianjone5 Junior Member Last Online: Jan 31st, 2017 18:19 Join Date: Jul 2015 Location: London	As I understand it, the glove test is performed at idle. Momentary pressure as you raise the revs is not important.

Jan 9th, 2016, 18:02	#8
colwyn Resident Ejit Last Online: Feb 19th, 2024 09:05 Join Date: Dec 2014 Location: Skelmersdale	I think it's vacuum at idle and as it under load it equalises to atmospheric pressure __________________ 96' 855 GLT auto 2.5 10v in dark olive pearl 97' Omega GLS auto 2.0 16v in oyster ABS controller problems, give me a shout

Jan 9th, 2016, 19:58	#9
bournricha bournricha Last Online: Jan 10th, 2017 22:14 Join Date: Jan 2014 Location: oban	IT is perfectly fine ,there will be momentary pressure on speeding the engine .The vacuum afterwards shows the pcv is sucking out the fumes as it should .Main thing is you have not got smoke puffing out of the dipstick hole . __________________ 1991 940 estate 2.3 125,000m.Under overhaul Previous convictions ;s70 ,855t5,745,v70, v70p2

Jan 10th, 2016, 12:18	#10
960kg Premier Member Last Online: Dec 28th, 2022 12:25 Join Date: Jun 2009 Location: Mercville	At idle it is supposed to be + 2or3 kilopascal....not even .5psi.....but definitely on the plus. __________________ Mercedes C320CDI Sport Estate 3 litre V6 7 Gear Auto Remap 290bhp 628Nm torque @ 1600revs 45.1mpg

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