Hi Max,
See below.
Max Heim wrote:
>
> Charley, I think you are misconstruing the "bedding in" part. That occurs
> after the engine is started, when you run it at a constant RPM for a
> certain period of time,
Not really, Max. In the earlier thread, it was averred that the
engine needed to be started immediately, to get the oil to it sooner,
otherwise extended cranking before starting would do-in the cam. This
was based on one (1) cam grinder's pronouncement.
> you want to get it running at this RPM ASAP, and not be cranking and
> cranking trying to start the engine (as could happen with a first-time
> startup with a new carburetor of a different type), and then fussing
> getting it to run correctly.
Aw shux, Max, after my first one 40 years ago, I haven't built an
engine that didn't fire right up as soon as I tried to start it.
Frankly, it's a matter of pride with me. It means I did everything
right. If the mechanic covered all the bases, it should fire right up.
So I think it was sage advice not to swap
> carburetors while the engine is being rebuilt with a new cam, even if the
> long-term plan is to change to a Weber.
I wouldn't put the Weber on it either, but it has nothing to do with
the cam. If the carb works it should fire right up. If it doesn't,
someone didn't take steps to ensure that it would.
> Twist's description of starting up a new engine is perfectly correct as
> far as it goes, but it doesn't go so far as to describe the process of
> bedding in a new cam.
Twist's tip was aimed at not putting running loads on the engine until
it had oil under pressure, so that no sliding surfaces would gall.
Sliding surfaces include the cam and lifters.
Max, this "process" is not unique to bedding in a cam. Any mechanic
is going to run a newly rebuilt engine in for a half-hour or more at a
couple of KRPM. Meanwhile the engine will be checked for leaks,
overheating, noises, etc, etc. No big deal. Might even tip a brew to
celebrate. ;^)
Cheers,
CR
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