Club 80-90 Forums

did a 125 mile run at 60+ this weekend and was surprised to find oil spatter all over the tailgate, once the engine cover was off the source is clearly the dipstick tube. Its pushing out at about 1ml per mile or so I guess based on the topup and return journey - anyway the "seal" at the top of the dipstick is a few dozen wraps of electrical tape so that's part of the problem, but the sudden change probably points to elevated crankcase pressure doesn't it?
Now putting 2 and 2 together - the bus used to smoke a bit on startup, but hasn't for a while so I'm wondering if there is a blockage in the CCV puck. what is the best way to check this, does the puck come apart? does it pull out? unscrew? any advice.

Oh and its a 1Z TDI engine
cheers
James

Have a look at any tubing going to the "puck" any blockage will force oil out of the dip stick tube [ask me how I know!!].

is the dipstick correct?
Has it been over filled?

Almost certainly an adapted/ substitute dipstick - looks to have been scuffed with a grinder to indicate fill level and like i said, the "seal" for what its worth is a load of (slowly unraveling) wraps of insulation tape.... no problem improving the seal at the top of the stick, but didnt want to bung it up until i knew that the crankcase could vent properly otherwise heaven only knows whats going to push out of where...
I'm presuming the puck contains some sort of screen so i wanted to get it off, clean it up and pop it back in again and check the pipes while there - i've had a gentle go at getting it off but its resisting and the last thing i want is a plastic retaining lug or something breaking off and dropping back into the engine... hence ask first... I''m also guessing that brittle plastic is probably happier coming off a warm engine than a cold one...
not likely overfilled - though once i've modified the dipstick i'l be verfiying the 4.5l level afresh for myself in case it sits higher/lower than the original measurement

OK so a bit of googling with AHU rather than 1Z got me an answer..
https://forums.tdiclub.com/showthread.php?t=337316" onclick="window.open(this.href);return false;

disconnect pipes and it pulls out with a slight rotation... Presumably 1Z is the same as AHU in this dept?
its also opened a can of worms as I'm now thinking about leaving this disconnected from the intake and venting to air/catching oil if it keeps my smoke free startup. is there any benefit at all venting the crankcase into the intake (other than environmental, and the particulates from burning off, rather than catching the catching the stray oil make that point pretty moot)

Breather fumes are not the ideal mix of gases for humans to run on so make sure you don't have the fumes entering your bus (less of an issue with a rear engine set up anyway).
Apart from that I'm not aware of a downside of venting the fumes to atmosphere although you may need some form of oil catch tank.