Howard Wilkinson wrote:

Paul:
    I strongly agree with your assessment about bearing spacing.......

I've

worked on 4x4 pickups for years and was really dissapointed when the newer
models went to two bearings close together.... the result has been worn out
castings, and bearing failures where they previously never bothered with
proper maintainance.    A taper is always a better way to mount something
like a prop hub, but matching tapers are critical, and often machining an
internal and external taper to match will be far more difficult than it
would appear.... you can't just depend on the taper attachment on the lathe
to do it for you.  On diesel engine where the front damper is often taper
mounted (Cummins) it is necessary to check with Prussian Blue to ensure

that

there is full contact.... if there isn't full contact it eventually will
wobble under the belt tension and ruin the damper and/or crank.
    I personally dislike crush sleeves..... I would much prefer to use

shims

to achieve proper pre-load..... That said someone who understands how to
properly use a crush sleeve (most people don't get it) can very quickly set
preload this way..... shimming is much more time consuming.

H.W.

I would send it out for the taper if I were making it and your
suggestion of checking it with blueing when it came back is a
very good idea since we are not producing
millions. Just one and there is plenty of time.

Paul Lamar

"Virgil N. Salisbury" wrote:

Lap it in with valve grinding compound. Perfect fit. Check progress
with prussian blue until perfect. Virg

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