Now this makes sense to me!
Now how about your opinion on starting an engine often to keep the oil up on
the walls etc. Its gone in a day or so anyway isn't it? I've always been
against the idea since start up is when the worst wear takes place so I
minimize the startups. Also at 40 cars I'd get nothing else done.
Should I just cut back on cars? Rational person would I bet.
-----Original Message-----
From: don dulmage <[email protected]>
To: [email protected] <[email protected]>
Date: Friday, October 29, 1999 7:12 AM
Subject: Re: [FWDLK] engine breakin
>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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