[Vwdiesel] Starter pinions in extreme cold

[Val Christian]

One cold morning several weeks ago, I was trying to start my diesel
tractor, and the starter was making growling noises.  I determined that
the pinion gear was fully engaging into the ring gear on the flywheel.
The growling noise was peppered with segments where the growling 
would stop, and the engine would turn a little, then the growling
would resume.  There was chatter type moises which, if slower, might 
almost sound like a solenoid dropping out.

I checked battery voltages prior to and during starting, and found them
to be reasonable.  The lowest voltage during starting was 10.8V, while
as the starter first engages, and the glowplugs go on full.  That's a 
good voltage, particularily considering the -15F temp that morning.

If I recall correctly, a starter pinion drive, the "Bendix" as it was
commonly called in the past, has a set of needle rollers internally.
I'm wondering if:

	a. The needle rollers, which "clamp in" for drive, and "let
	loose" for overrunning, might be worn, and therefore just
	loose enough to not grab well when cold, or,

	b. the lubrication in the drive assembly, where the needle
	rollers are, may be viscous enough in extreme cold, so that
	the needles fail to "clamp in" when the assembly should be
	driving.

Any thoughts?

Val

ps: I found a place that carries electrical parts for tractors, mowers and
other equipment.  The parts for the tractor's Hitachi starter and altenator
seem to be about 1/4 of the dealer prices, so I'm inclined to "buy ahead"
and get a solenoid, drive, bushings, brushes, and for the altenator 
brushes and bearings.  Then I looked at my parts pile, and saw three
"bendix" pinion assemblies for my 69 Ford truck, and though perhaps I 
should reconsider the buy ahead.  Then I remembered that I paid $4 each
for them, and didn't feel so bad.