[Vwdiesel] 81 pickup starter click but no crank

[Will Taygan]

I'm helping a buddy with his 81 diesel pickup

The starter went out a week or so ago, so we put in a working exide starter from my junker 82 diesel pickup.

It worked for a few days.  Then it stopped working.  He cleaned up the ground and electrical connections and it started working again.

Then it stopped working again.

The solenoid clicks.

We're working in -10F in the snow, but the block heater is plugged in.

12.7v at the battery and at the big nut on the starter.  Just UNDER 10v at the solenoid when the ingnition is in cranking position.

Starter whirrs when I short the big nuts with a screwdriver.  Engine turns over when we turn the ignition switch to crankig position while the starter is whirring.

Is this another bad starter, or is there anything else it could be?


Will.