3020 gas starter

[Hilltopper]

I am working on 3020 gas. It has started locking the selenoid in when you try to start it. It gets hot quickly. Necessary to pull ground to get it to stop. It cranks very slow recently. The battery is the second new 3et. It has had the cables replaced with new heavy ones. The start switch and selenoid are new. It cranks like a old draggy starter than at other times will spin very well. The bushing look o. k. Running groud directly to starter bolt had no effect. I have decided to pull the starter and take it to an electrical shop for testing. O'rielly could find nothing wrong on their tester. Stumped

 

[HollyFarmer]

Used to have a 3020 gasser, and it ate starters like kids eat candy. Never really figured out what was causing the problem. Always assumed, it was a timing. spark issue that caused to to crank good one time then slow the next. Finnaly gave up and traded for a 4020D.

 

[D-]

Possibly burrs on flywheel, worn grooves in armature, etc. holding drive in.

 

[buickanddeere]

Is the mechanical spark advance sticking?
Has there been a hydraulic pump destroker installed?

 

[Hilltopper]

There is no destroker on the pump. I had not considered an distributor advance problem will go there next. It has gotten worse lately. Sometimes fires right up other times sounds like a weak battery. Shaking the steering has no effect as the problem is there as soon as you try to crank it. Thanks