I have watched this thread for a bit and would like to completely
dispell one idea.
Cranking the engine to get oil pressure is not a good idea. Virtually
all serious engine wear takes place during starting . That is because
the oil is not present in the pressurized state. The cylinder walls are
relatively dry and all the oil has dripped off of the camshaft. This is
at least twofold worse on a brand new motor as some of the areas have
never had oil to them yet. Cranking the engine over on the starter till
you have oil pressure is the longest method to get oil to the engine and
even then the only oil going anywhere is in the oil galleries provided
of course the oil pump is turning fast enough to pick it up. The NO 1
cause of camshaft failure in a new engine as any cam manufacturer will
tell you is the engine was cranked for extended periods of time so no
oil was sprayed up off of the crankshaft onto the camshaft and lifters
and the assembly lube cannot carry the load of lubing the cam that long
(long means a minute or so.) If you want to be good to your engine make
sure the timing is right on and there is some fuel in the carb and fire
and run it immediately. The engine should not be allowed to idle for the
first twenty minutes or so. This way it will get oil everywhere within a
few seconds and will stay lubed as the cam and lifters get familiar with
each other. No damage will result. As an engine builder of some 35 years
I would not cover an engine that is starter cranked for oil pressure and
neither would any cam manufacturer. Dispite the fact that it seems the
right idea because it is complicated and time comsuming it is excactly
the worst thing you can to for your engine and more new engines are
damaged that way than any other. I am sorry if this offends some of you
but it is the absolute truth. If you want to go a step further then
preoil you engine before starting either by running the oil pump with a
preoiler shaft with the distributor removed or with a pressurized
preoiler. What you want is the engine running and spraying oil inside as
quickly as is possible. It takes only a few seconds to get oil pressure
and internal spraying when the engine is fired up immediately but it
takes minutes on the starter. Loads are the same but the time is much
longer with the starter cranking deal and there is absolutely no oil
spraying on anything inside the engine.BTW it takes less than 5 minutes
to completely wipe a camshaft lobe.
Don Dulmage
Master Mach , Master Tech ASE
Lars Larson 56 Plymouth wrote:
>
> Dave H has presented most the info, also check your shop or motors manual?
> There is also an association of national engine rebuilders, my rebuild came
> with a detailed breakin procedure and guarantee, maybe U can find one of them
> like at a Jasper or other rebuilder. Cant seem to find my copy, but its 7
> yrs old so may have disappeared.
> If cranking to build up oil pressure, good to do each spring, dont forget to
> remove the LOW VOLTAGE lead from dist to coil- not the high tension wire.
> L.
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