No crank when hot

[Flinty]

As the title states, my '92 won't start after I've been running it for a while. Have any of you experienced this before? My search revealed clutch switch problems, contact problems, and ground problems. Couldn't find any threads with heat related issues. Any gut feelings out there that you might want to share with me? My next step is to get a hammer and give it a good whack the next time it won't start and see what happens. Thanks for looking.



Jon

 

[RedRamAndy]

Hello Jon,
I had an old Coronet that suffered from that once. Once the windings in the starter got hot, it lost it's cranking power. In your case though, I'd lean toward the contacts in the starter solenoid housing. My wife's '90 New Yorker has the same type starter on it only smaller. In 250 thou miles, I've put in a few sets of contacts, nothing else. It's a great starter. These contacts burn down and give a less positive closure to the circuit as they get older. Couple that with a weak hot solenoid magnet coil, and you could have your problem right there. I'd go for the contact kit myself.

 

[JLEONARD]

Now that you mention that I had a Ford pickup that was doing the same thing... . the drive gear bushings were so shot that the (6 month old rebuilt) starter couldn't turn but only when hot.

 

[Greenleaf]

I have pulled many starters from these diesels and the contacts are always burned. I have never seen one wear out. I know some report that they had to "buy a new starter"... ... . but, I wasn't the tech working on that truck! LOL



I have had the contacts stick and allow the starter motor to turn and burn the motor out. Never seen one wear out.



Pull the motor and open it up. Take the gears apart and clean/lube w/high temp grease. replace or clean the contacts. Some like to sand the armature to clean the contact points.



My 1990 trk at 320-some K miles has the original starter motor with all original parts.

 

[Flinty]

Here's what I found:

The contacts had lots of meat on them but the one the battery cable was connected to was twisted, making the plunger ride on the edge where the arrow is pointing to.



I squared the surfaces and cleaned everything up. Notice the line on the one contact. It has a hardened insert that the plunger rides on, like you see on planer blades.