[DeTomaso] clutch?

[Göran Malmberg]

JT,
You have a very good point here!
Goran

A strongly sprung pressure plate will also increase the load on the crank's
thrust surface and bearing.  When the clutch is depressed at idle (e.g. at a
traffic light) the engines oil pressure is relatively lower and the crank's
thrust surface riding on the center main bearing is susceptible to wear.

Due to another issue, a previous engine build of mine had only about 15lbs
at idle and I was running a heavily sprung pressure plate from McLeod.  In
this environment, the crank's thrust surface suffered wear.  The crank was
replaced anyway because it was cracked which in turn damaged the main
bearings causing the low oil pressure in the first place.  However, it did
enlighten me as to the correlation between low oil pressure, strongly sprung
pressure plates and crank thrust surfaces.

I now better appreciate higher oil pressures at idle and never start the car
with the clutch engaged.  I wait for oil pressure to build before depressing
the clutch to spare the cranks thrust surface.

Happy Thanksgiving !

JT