Gentlemen or Ladies,
While I'm in the process of disconnecting this to that on my 1969 MGB, I
have come upon a question I think? When I pulled the crank from the engine
(rebuilt prior) in the process of getting the parts to the machinist I found
the oil squirt holes in the connecting rods facing the carb side of the
engine. I don't know how many miles this engine has on it but it's certainly
not a recent rebuild.
In reading I came across the below statement and now wonder when I begin
reconnecting this to that which way the squirt holes should go? The paragraph
regarding the purpose makes a lot of sense but I thought someone out there
might also have some knowledge or experience which could ease my concern.
Thanks for the response,
Gregg Baker
"To be very clear about this, the oil holes have ALWAYS faced the distributor
or spark plug side of the engine and NEVER faced the camshaft or carburetor
side of the engine.
The purpose of these squirt holes is to lubricate the piston pin, the cylinder
bores, and bathe the bottom of the piston as an adjunct to cooling. Were the
squirt holes aimed towards the camshaft, due to the location of the camshaft
in the lower part of the cylinder bank, the stream of oil would be mostly
blocked by the cam and prevented from shooting upwards against the piston and
piston pin during the critical number of degrees of crankshaft rotation
lubrication can possibly occur. This would eventually result in extreme piston
pin wear within the piston and the very real likelihood of piston failure, not
to mention increased bore wear as well. The cam itself receives abundant
lubrication from both the pressure galleries in which it's journals spin and
residual oil flowing down the pushrod bores from overflow at the rocker
shafts, not to mention oil cast from the main and rod end bearings at the
crankshaft."
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