> The air oil separator tube that goes over board may
>have froze up in the subfreezing temps and the crank case pressure forced
>the oil out the dipstick tube.
>Joe Horton
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Make sure you have no "low points" in any of your crankcase vent lines.
What I mean is that there should be no low spot in the tube between
any two mounting points. Any condensation in the tube can collect and
build up in these low points and eventually close the tube entirely
when frozen.
If a crankcase vent tube rises vertically from the engine, continue the
rise to the high point and then a continual decent to the exit. Hopefully
any condensation will either run back to the crankcase or exit the tube.
Also, make sure you use large enough diameter lines so that drops
of moisture collecting on opposite walls can't bridge over.
I had a clear vent tube for about the first 50 hours of flight time and I
was amazed at the crap I saw in it. Also, unless you have a large
rigid line, it doesn't hurt to take a spring of sufficient size, stretch it
to a considerable length, then insert it inside the tube so the line
won't collapse.
I seem to recall hearing of aircraft engines that had lines freeze and
blow seals but I don't recall any of the details.
Larry Flesner ( just 2 hours of KR time in the last 30 days and needing
a fix !!!! )
