Catch can

[brettj20]

Had a small issue with my diesel yesterday, it was starting to rev up by its self, found oil laying in the intake, I order a splash guard, so that should fix my issue, Is there any one runing a catch can on their diesels? I was thinking of runing one just for peace of mind.

[vwtyp133]

Couldn't hurt; will probably mount one when the new engine goes in. However, the "splash guard" does seem to help prevent runaways.

[Dakotakid]

In addition to the plastic splash shield, are you running an old style vacuum pump....it would be helpful if you guys who want help would identify the car in question. If it is an old style vacuum pump and the diaphragm in it is shot, the engine will draw oil this way to contribute to a NASA-style lift-off (run-away engine).

[brettj20]

I have a 83 ls custom, would that that a old style pump ? If so where can I get a replacement

[82vdub]

If it has the large diaghram, it's the old style. My 82 has the old style and I think 83-84 was the change over year. The newer vane style pump is much more reliable and doesn't use that rubber bladder to keep the vacuum going.

[brettj20]

Got pictures of the 2 different pumps ?

[TylerDurden]

Old one has a diaphragm tangental to a tall shaft, new one has a can on a stub.


(not my pic.)

[brettj20]

Thanks a lot, looks like I have the old style, I will order a rebuild kit just to be safe.

[82vdub]

You can test your vacuum system to see if the rubber is broken or working. Or, just up for the $25 or so additional and get a vane pump and never have to worry about it again.

[damac]

My jetta engine was getting major blowby recently. Tons of white smoke enough to fill engine bay out filler cap when taken off. Also oil was always seeping from valve cover.

I have a rotary vacuum pump and installed a block off plate with a nipple on the lower block port and t'd that into the bottom of a pvc catch can i made inline with a couple stainless scrubbing balls sealed inside. The valve cover hose went to one side then the other side to the intake. So all the oil stayed in the system, nothing to drain.

I still had oil coating the intake but never enough to runaway or coat the air filter, etc.

I got a different engine now and still did that t into the intake but I took out my inline catch can.


My car was getting so bad it would smoke white out the pipe even at idle? I assumed that and my big smoke patterns had something to do with blowby.

No more smoking now for me, but I was kind of forced into this situation since a family member overheated my td motor until it locked up

[Fatmobile]

When the blowby is traveling from the block to the head,
while oil is trying to go the other way,
if it's traveling fast enough it can carry oil with it.

I think the block vent helps slow the gasses flowing up through the head by allowing another path to the intake, allowing more oil to settle back to the oil pan.

Bigger is probably better in this case. I've been using 3/4" silicone hose for the TDs.