Blowing oil out of the dipstick tube seal

[gldgti]

be carful putting too much stuff in the pipes, you might make your dipstick problem worse.

worn rings are a big contributor to this problem - my 1.5 was saturating my air filters with oil through the head breather (which vents gas from the crankcase indirectly, but it does work) until i made a scavenger with a glass jar and some scourers (the metal kind ). this way i made sure that i wast restricting the system and i could keep an eye on how much oil i collected.

dont mean to be a wet towel, but make sure your rings are good. my 1.5 was running just fine with 2.5mm ring end gaps (yes, 2.5mm - wear limit being 0.5 i think...) apart from burning lots of oil it had plenty of horsepower. since the new rings, it doesnt use any oil, and doesnt leak any from the dipstick hole, which has no o-ring or felt washer of any kind (metal on metal). its really a pressure thing (excepting awesome race-braking).

have fun...

btw - how far do you guys rev then? im not game enough to break 5000, since all i can think about is the 1mm or so clearence between the head and the piston crown!!!!

[v8volvo]

Jake--haven't been around this board much--you're racing again? I'd still like to see the GTD in action--when is your next local event?

[fspGTD]

Nope - still working on putting the rebuilt head on.  Just moved the car into a heated garage though, so I can work comfortably during the winter...  

I don't suspect bad rings on my motor.  It may be accurate to say that they aren't designed to run at the RPMs that I am using them at though.  The redline of the 1.6l NA diesel is 5500RPM, and 1.6lTD is 5100RPM.  I've run my 1.6lTD up to about 6000RPM, and there only seems to be a build-up of presure in the crankcase from excessive blow-by at those high RPMs.  I may well experiment with even higher RPMs yet, so I am looking at improvements to the factory crankcase evacuation system.

[VWRacer]

Nope - still working on putting the rebuilt head on.  Just moved the car into a heated garage though, so I can work comfortably during the winter...  

I don't suspect bad rings on my motor.  It may be accurate to say that they aren't designed to run at the RPMs that I am using them at though.  The redline of the 1.6l NA diesel is 5500RPM, and 1.6lTD is 5100RPM.  I've run my 1.6lTD up to about 6000RPM, and there only seems to be a build-up of presure in the crankcase from excessive blow-by at those high RPMs.  I may well experiment with even higher RPMs yet, so I am looking at improvements to the factory crankcase evacuation system.

Jake, I'm not surprised to see your crankcase pressurise at higher RPMs. We run into this problem all the time with racing engines. The usual fix is to plumb a crankcase vent line into a dry sump scavenge stage. A good tight connection can lower the crankcase pressure to 10+ inches of vacuum even at full-tilt-boogie... ;-)

While you don't have that option, you would still do well to enlarge the existing vent, and/or add another from the cam cover.

Stan

[gldgti]

interesting point on the blowby -oil problem...

as i said before ,i got a 1.5, and my dad has one too. his engine is a year younger than mine (79), and they are almost identicle except for one thing - he has a crancase breather which goes up, joins to the rocker-cover breather and then into the airbox, whereas my engine ('78) only has the rocker cover breather.....

maybe this was just for pollution control regulations - australia might be different from US, so that might be it....

6000rpm!!!! :shock: does that mean my NA 1.5 which has a 8mm shorter stroke than your 1.6 would rev even more?

[fspGTD]

That 1.5l crank breather is a factory VW parts kit to correct too much oil on air filter syndrome in 1.5l diesels...

excerpt from "Four cylinder Diesel 1977-'83, Protraining" (I think someone recently scanned this whole book and posted it up on this board - do a search!)
page 130
"Oil in air cleaner
1.5 liter diesel, Rabbit and Pick-up.

To prevent oil from entering the air cleaner on 1.5 liter diesel engines, a modified breather hose assembly should be installed.
First check to see if the modification has already been installed, if not: ..."