Nelson Yaple scribed:
Subject: In need of net wisdom
> ... when I accelerate at about
> 3K RPM it knocks fairly loud only during acceleration
> (load). Is this Main Bearing, Big End Bearing or just the
This is >most likely< the big end (rod) bearings. At this milage, the
mains, & thrust bearings are candidates for replacement at the same time.
It could also be some piston slap. What hapepns with worn/knocking
rod bearings? Well, every time the rod goes up and down, the crank
slaps back and forth in the bearing, hammering it a bit thinner. Your
oil prfessure drops due to greater clearence. The bearings are cheap,
so who cares if they are destroyed? Well, the crankshaft is also at risk.
the battering, or reduced oil can result in accelerated crank journal
wear. The bearing shell could work loose and spin, (spun bearing), which
will likely do a number on the crank, or in some cases, wedge, seize on the
crank, and cause the rod to continue rotating with the crank, resulting in
a rapid cartoon-like exit through the side of the block...
________
/___ _ \ Roger Garnett (Roger_Garnett@cornell.edu)
/| || \ \ Agricultural Economics | "The South Lansing Centre
| |___|| _ | 3 Warren Hall | For Wayward Sports Cars"
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