VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: rodpaslow on April 19, 2012, 09:04:32 am
-
I broke this black round thing on the valve cover that goes to a provent unit - do I need a new round thing or pcv valve, or can I get away with just running a line from the valve cover to the provent 200?
My pcv or round black thing on the valve cover is open, there is no restriction or filter (I don't know if this is correct or someone took the guts out of it). Is this correct for a 1.6 TD ('91 vintage)?
-
It's an oil separator - it's job is to reduce the amount of oil coming out of the breather, keeping it in the engine. You can certainly run a line to the Provent without it, but you're going to end up with more oil in the Provent than you would otherwise.
You can get a new one, but they're kinda expensive for what they are. Listed at about $40 through the first supplier I checked. I'd probably do it if it were me though.
-
It's an oil separator - it's job is to reduce the amount of oil coming out of the breather, keeping it in the engine. You can certainly run a line to the Provent without it, but you're going to end up with more oil in the Provent than you would otherwise.
You can get a new one, but they're kinda expensive for what they are. Listed at about $40 through the first supplier I checked. I'd probably do it if it were me though.
if everyone else is like me, then they should have about 40 of these laying around..
i know i have a TON of them..
i imagine you could find a used one somewhere cheap or free..
-
Thanks, I'll probably go to the pull-yourself auto wrecker and see if they have any MK2's and pull one off.
I know I have a spare, but as usual i can't find it...
-
anything one can do to reduce the amount of oil going into the intake thru the tube that comes out of that thing going to the intake tube?
-
anything one can do to reduce the amount of oil going into the intake thru the tube that comes out of that thing going to the intake tube?
catch can anyone?
-
isnt that what that funky looking thing is, is a factory catch can?
-
isnt that what that funky looking thing is, is a factory catch can?
lmao, no..
its an oil vapor separator, thats about it..
it doesnt actually CATCH anything..
-
I have an older NA (90 1.6) that I use mostly in the winter. I checked it and it doesn't have one is has a mesh of some kind in the valve cover. I suppose that why a NA doesn't need this?
-
I have an older NA (90 1.6) that I use mostly in the winter. I checked it and it doesn't have one is has a mesh of some kind in the valve cover. I suppose that why a NA doesn't need this?
it was integrated into the valve cover on the OLD engines..
-
My 86 valve cover also has the mesh inside and came with the pcv to the intake.
I deleted the hose and inline heating element. Then ran a hose from the pcv to a small breather filter and mounted the breather filter inside my intake cone filter. ;D kinda ghetto but it works and its inside the fender anyways so it not visable
-
does having or deleting pcv have any advantage or disadvantage?
-
does having or deleting pcv have any advantage or disadvantage?
Question:What is the PCV valve and what does it do?
Answer:The blowby vapors that end up in an engine's crankcase contain moisture as well as combustion byproducts and unburned fuel vapors. The crankcase is sealed to prevent the escape of these gases into the atmosphere, but the vapors must be removed to prevent oil contamination that leads to sludge formation. The positive crankcase ventilation (PCV) system siphons these vapors from the crankcase and routes them into the intake manifold so they can be reburned in the engine.
I think deleting it ie. "cover/plug the hole" is not a good idea. However a lot of people will run breather filters and add catch cans for to remove the possibility of oil reaching their intake.
Catch cans like provent 200 seem to be the way to go. Retaining crankcase ventilation, recurculating fumes and removing the chance of oil getting into your intake.
Running a breather filter on your VC works. If you dont mind smelling fumes when your windows rolled down on a nice day and cleaning/replacing it on a somewhat regular basis
My .02 cents
-
ok, but on a diesel, isnt a little oil in the intake just added fuel and upper cylinder lubricant?
-
The MK3 PCV pucks have a 3rd port for a hose from the front of the block,.. like the AZZs.
-
I decided to cut it up and actually see what the function of it is. I can't post the pictures now, I will later.
There's no gauze or anything related to actual oil separation. It actually is almost opposite of a gasser pcv valve. It has a very light compression spring in it with a diaphram similar to a boost/vacuum can diapham and it is almost at the top of the can. If you have blow by or slight crankcase pressure it will keep the opening to the outlet open. If for some reason the outlet to the can has a vacuum the valve shuts closed - the diaphram is pulled down against the spring and closes the opening to the outlet. (I also would think if the vacuum pulling from this can is bigger than the blowby you have, the valve would be opening and closing often. It doesn't have to move much to close the outlet off, maybe 1/8")
I think what vw was trying to do is not have a vacuum situation happening in the crankcase. I'm not sure the reason for that.
I have purchased a new valve and will be installing it as soon as I receive it!
-
(http://i1134.photobucket.com/albums/m618/rodderboost/4265030273_330.jpg)
(http://i1134.photobucket.com/albums/m618/rodderboost/4265028993_330.jpg)
(http://i1134.photobucket.com/albums/m618/rodderboost/4265028609_330.jpg)
These are the pics. I think it's pretty important to have one, even if it doesn't do much to separate the oil from the air.
-
By the way, I'd take a spare if someone wants to sell one cheap....(vw wants $100 cad new, paid $60 for online aftermarket)
-
It acts as a one-way valve, keeping air flow moving constantly through the block and into the intake. It's also a flow restriction, which isn't as important on diesel engines, but critical on fuel injected gas engines. On gas engines, the crank fumes are introduced to the intake air after the MAF sensor, and without restriction, could cause a lean condition or rich condition depending on crank case contents. In diesels, it just slows the flow of oil vapours.
-
...isn't as important on diesel engines, but critical on fuel injected gas engines. ... In diesels, it just slows the flow of oil vapours.
Maybe in an ideal world. If you get a bad enough combustion chamber -crankcase leak, like a holed piston, it will blow enough oil up through the tube to send the engine into runaway and catastrophic failure. The CCV is slammed shut by this excessive pressure, cutting off the fuel (lube oil) to the motor, and may save parts of your motor, or save you from parts of the motor!
-
I never thought about that, but if you had a runaway situation or something more catastrophic - like you mentioned, it's possible the vapours being pulled from the intake could (I say could) be large and this would shut the valve and save the motor or definitely parts of it! Works for me..
-
im pretty sure mine is hollow.....
-
That's what I thought with mine initially as I couldn't see the spring from either the inlet or outlet. It could be though, I know in Canada, I think the only cars that got this through the mk2 years was the turbo diesel. The NA has a different setup directly into the intake.
-
I've got the new one installed and for some reason I'm still having problems with either it or the provent 200. The car running highway speed doesn't use any oil, but as soon as your stopped at a light, you can see and smell blue smoke, and burning oil smell if wind is blowing the exhaust back towards the car. I've stopped at my house pulled the cover off the provent 200 and the smoke stops immediately. The provent filter is new, not over 5000 kms on it.
Has anyone else had a problem where they were stopped and the car was burning a slight bit of oil? and only stopped or slow speed?