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General Information => Troubleshooting => Topic started by: Brianshayne on July 25, 2013, 06:56:39 am

Title: Blowby - is this okay?
Post by: Brianshayne on July 25, 2013, 06:56:39 am
After most drives, I need to reseat my dipstick -- about an inch and a half or so.

Is this okay? Could my leaky valve cover gasket be causing this? (Sucking in air?) Also, notice not so much steam -- maybe smoke? Something wispy that comes off the valve cover gasket area while running.

Temps are good, coolant level is good.

Unrelated: Tried upping my fuel -- got it up, wasn't sure what kind of smoke SHOULD be present, and no EGT so I chickened out and turned it back down.
Title: Re: Blowby - is this okay?
Post by: CRSMP5 on July 25, 2013, 07:19:10 am
when it runs away its too much blow-by...

vc leaks due to the same reason dip stick pushes  out... honestly...

i would add a catch can that has a return into the block via the plate by the vac pump.. so any oil it blows out will drain back in once off.. and run it till you can rebuild..
Title: Re: Blowby - is this okay?
Post by: libbydiesel on July 25, 2013, 07:23:59 am
If a catch can is added with a return to the block it must have a check valve in the drain or it increases the risk of runaway. 
Title: Re: Blowby - is this okay?
Post by: burn_your_money on July 25, 2013, 08:45:36 am
A leak in the vacuum system can cause extra air to enter into the engine. I'd investigate that. Thankfully it's not a MB so it won't take very long  8)
Title: Re: Blowby - is this okay?
Post by: damac on July 25, 2013, 09:36:05 am
I think I have been lucky thus far, even my nastiest used engines I have come across that had blowby out the filler cap, never pushed the dipstick out.

My 85 jetta came with an engine that had a good amount of blowby and I made a catch can out of pvc and stainless steel mesh balls stuff inside.  I could easily breath through it so it wasn't restrictive, and in the middle cavity I put a hose that goes to the old block off plate location.

I think it did help a bit as far as going into the end of the intake.
Title: Re: Blowby - is this okay?
Post by: CRSMP5 on July 25, 2013, 11:06:35 am
ive seen them push oil up out of the dipstick... not like watergun.. that be sweet though.. but enough for the customer to *** abt the oil drops on the ground.....

libby.. at the point of time ive seen people build a catch can like that.. it was no longer fed into the intake... they were using it as a way to catch the oil to let it run back in... and sadly it worked for them... old cheap 1.5d users of the 80s...
Title: Re: Blowby - is this okay?
Post by: Brianshayne on July 25, 2013, 01:27:51 pm
I understood about zero of this thread so far, sorry guys -- slower maybe, I'm still pretty dumb.

No oil out the dipstick -- some wispy from the valve cover (as it's leaking) only saw this once though, on a dry day.


No PCV on this motor? So catch can eh? How would I tell if it has one? Motor is stock at the moment, minus a very smallly adjusted fuel screw (was blowing vefore though)
Title: Re: Blowby - is this okay?
Post by: CRSMP5 on July 25, 2013, 01:55:56 pm
pvc built into the vc... never seen diesel one plug up...

no oil.. do not worry bout it.. i bet your dipstick has a vibration and it poppig up due to that...
Title: Re: Blowby - is this okay?
Post by: Brianshayne on July 25, 2013, 02:00:59 pm
Oil filler is under pressure when you remove the cap -- normal too?
Title: Re: Blowby - is this okay?
Post by: burn_your_money on July 25, 2013, 03:22:14 pm
On a running engine, very normal to have pressure under the oil filler.

I'm 30 minutes from you. If you want to swing by some time I can have a look at it and tell you what I think.
Title: Re: Blowby - is this okay?
Post by: air-cooled or diesel on July 26, 2013, 04:36:50 am
A leak in the vacuum system can cause extra air to enter into the engine. I'd investigate that.
this is the first thing to do. check all vac lines/connections, and brake booster for rust holes/leaks.
simple, effective step to knock off to check list.
Title: Re: Blowby - is this okay?
Post by: air-cooled or diesel on July 26, 2013, 04:43:05 am
On a running engine, very normal to have pressure under the oil filler.

I'm 30 minutes from you. If you want to swing by some time I can have a look at it and tell you what I think.
Oil filler is under pressure when you remove the cap -- normal too?
as long as oil isn't getting pushed out thru dipstick or valve cover area; which would indicate way over pressure inside. some pressure and pulsing is normal.
Title: Re: Re: Blowby - is this okay?
Post by: Brianshayne on July 26, 2013, 06:50:51 am
If you'd be down, that'd be great. Once I learn, I learn - but I'm better visually. Maybe you can show me how to reattach my residual screw as well, seems to have come out

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