Peter,
I assume you have the crankcase ventilated in some way already so here
is
what comes to mind:
Are the bores known to be straight and true? If they weren't and you
just stuffed in the new parts that could be it. If you didn't scuff up
the
bores the rings may take a long time to seat (or may not at all!).
Are the ring end-gaps staggered? A silly question but I've found this
on
a problem engine- rebuilder was a first-timer and had no clue. Also stuff
happens sometimes on late nights reassembling.
Is the ring end-gap excessive?
Last and worst- you may have broken rings. If there was ANY ridge at
the
top of the bores it can break the new top rings. Also, if there was too
little end gap that will do it too the first time it gets hot.
If I was going to speculate, I'd say broken rings since the blow-by
sounds quite extreme. Had this happen on a Toyota engine I race prepped
many years ago. Set it up tight and pylon raced it the same morning.
Broke 4 rings due to insufficient end gap- a slight miscalculation at 2:00
AM that cost me big-time. So much blow-by it blew the PCV hose off and
blew oil smoke into the steering column which then entered the cockpit. I
still remember that feeling in the pit of my stomach....
Try a compression check and a cylinder leak-down check if you have
access to the equipment. Any imbalance in the cylinders will point to the
problem. Let us know what you find.
Clay
______________________________ Reply Separator _________________________________
Subject: tuned LBC engines
Author: Non-HP-owner-triumphs (owner-triumphs@triumph.cs.utah.edu) at
HP-Boise,mimegw3
Date: 9/10/96 7:57 AM
Hi all,
has anyone an idea, why crankcase pressure builts up and how to get rid of it
without using at least 4 tubes and a 2 gallon oil catching tank.;-)
One thing is known allready:
- the pressure is built up by fume pressed "through" the piston rings during wor
k
stroke
How can this happen with fairly new pistons, sleeves and rings, but compression
raised to 10.5 .
IMO, CR , compared to the pressure during work stroke, can+t be the reason.
Anyway, the wildest guesses are preferred too.
Thanks in advance,
Peter Juergens
Germany
PiJay@t-online.de
62+TR4 daily
>>> Don+t fasten the seat belts, just die like a man! <<<
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