[T3] BBbbrrrrrr!

[Jim Adney]

On 7 Jan 2014 at 21:04, Dennis Stiefel wrote:

> No knocking she just shut down after about 60 seconds of running trying to
> back it out of my little shed. It acted like it was bogging down just before
> it quit. When I tried to start it would just barely turn even when I put the
> jump box on it.  I'm just going to leave it alone till we start have more
> normal weather for around here this time of the year at the end of the week.

I suspect you're right about this being serious, but it's still worth 
trying again when it's warmer.

This brings 3 things to mind:

1) The OE #2 main bearings came with steel inserts if the cars were 
destined for "temperate" climates. If you have experience with both 
styles, they are easy to tell apart just by feeling the weight. 
Otherwise a magnet will detect the steel. The steel inserts 
apparently kept the bearing from shrinking down on the crank when 
cold weather caused the case to shrink and increased the "squish" on 
that bearing. I don't fully understand this, or why it was not 
necessary for the full circle bearings. I hear that replacment 
bearing sets no longer come with the steel inserts. If that was your 
problem, then the cold may be responsible, but 9 F doesn't seem all 
that cold, at least to me.

2) It's very important that the case be cut to the exact correct 
diameter to give just the right amount of squeeze to the main 
bearings. Too tight or too loose are both bad. You opted for a local 
guy with a (probably) worn align boring bar, which would cut 
oversize. A journal seat that's .001" too large won't have enough 
grip on the bearing to hold it and keep it from turning.

3) If a bearing spun on you now, I doubt if you should blame it on 
the cold weather. It would have happened eventually. At least this 
way it happened at home, and not halfway to the Invasion.

-- 
*******************************
Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
*******************************