The first race engine I built filled the catch tank. Cause was severe
blowby, one liner was not bored round. Lesson learned after that incident
was all parts go to the machine shop for checking before engine is built.
My measuring tools are not precise enough, and for what it costs for them
to check things out it is false economy not to do this...
I believe an additional cause of filling the puke can was the fact the
engine used a TR4 breather pipe modified to take the trap out as the
primary vent. On right hand sweepers the oil level was sloshing high enough
in the block that oil was entering the breather pipe. I did two
modifications, first I had a baffle installed in a stock oil pan. Second, I
rebuilt the engine using a TR4A block that uses a freeze plug in the
breather. I left that freeze plug in place, and drilled a one inch hole in
the fuel pump blanking plate, welded up a bung and ran my primary vent host
to the catch tank from there. Still run a hose from a stock valve cover
vent to the catch tank.
Those mods combined with a good set of pistons/liners/rings seems to have
cured the puking into the blowby tank. The Carousel at Road America is a
VERY fast, long, right hand sweeper that put this to the test, and the
catch tank stayed as dry as I could have hoped for.
IMHO, 3 to 4 ounces a session is on the high side of acceptable.
At 11:22 AM 5/23/2001 -0400, Ronald R Gates wrote:
>We ran V.I.R. a few weeks ago and noticed that we had about 3 or 4 ounces
>of oily stuff in our crankcase overflow bottle after each 8 - 10 lap races
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