Starter cranks at half speed

This is where the common years ago automotive electrical shops had starter torque load testers. Testing on bench with actual live torque load at various amp draw. One of the old tools that have been done away with that worked. Most every small town had a auto electrical shop, but with a parts changer society those shops disappeared.

I have seen on several occasions where there was corrosion between the battery cable and the crimped on terminal. Everything looked great but there was a voltage drop on the cable. Removed both terminals and cut off the corroded ends of the cable and crimped on new terminals and it cranked like it should. I was not the first person to troubleshoot that cranking problem.

Crimped ends looked OK but can check again. Will do a voltage drop test to confirm.

replace starter

I have to wait until he wants to do it or has time. I'll help but don't want to do all the hardest work.

I talked to him today and he said he changed the ground cable and it cranks faster and didn't get as hot. How much faster I'm not sure. He's hoping we can get it primed. I'll know better on Sunday.