1989 Ford Class A Starter Issues

[Bouchbri25]

My RV starts fine but when it runs for a while (even 10minutes) and I shut it off, the starter doesn't want to re-engage (cranks very hard and won't start). I've replaced starter solenoid ignition switch battery and starter including wrapping the starter in heat wrap and still have the issue... Any ideas?

[38Chevy454]

The problem is heat related as you have determined. Heat goes up, so does resistance and subsequent amps required.
Some suggestions:
1) Check all electrical connections to make sure they are clean and tight. Want zero resistance due to connections.
2) Run a separate ground from starter to battery. Just as important to get power return negative side circuit to be direct path as the positive circuit side.
3) Run lower gage (bigger wire) positive cable. A lot of cables are 4 ga, you can run 2 ga or even get a custom cable made using welding cable in 0 ga. Bigger is better!
4) Check timing, if too advanced the engine struggles with the combustion load against the starter.
5) If all else fails, you can put an ignition cutout switch. You turn ignition off, then crank engine to get it rotating over, then flip the ignition switch and it will fire right off. Only needed when hot or cranking too slow.

[Bouchbri25]

Thanks for the great ideas. I did check timing and I was considering running another ground. Does it have to go back to battery or just to the frame? I love the ignition cutout switch idea too if all else fails. Thanks again!

[TQ60]

You have been swapping parts and not testing...

Get a voltmeter and make measurments everywhere.

1 across battery with leads pushed into posts
2 from ground to post
3 from podt to wire
4 from block to neg post
5 so on
6 so fourth...

Advanced timing will cause harder start but 89 is computer controlled but distributor still can be turned.

The coil is seperate so find an old spark plug or 1/4 bolt and remove coil wire at distributor and insert bolt or plug and rest it by ground...do not hold...

If combustion is causing issue then will crank just fine with no spark...

Combustion may not be cause...bad connection may be cause and combustion too much for issue.

Sounds like a connection is failing and before you change anything else use a voltmeter to see just where the voltage is dropping.

Also verify battery is fully charged.

Alternator may not be charging battery well.

[Bouchbri25]

Replaced the cables as suggested but as it turns out the issue was a bad clutch fan. It was spinning but never really kicked in and the temp was causing all of my issues. Once I replaced it the starting issues and running and shutting down randomly all went away. Thanks for all the help

[JohnRR]

Thank you for the update, you may also want to consider checking for one of your local auto parts stores that would have the capability to run a free starter load test for you to check the starter current draw.

If a starter is drawing excessive amps it may very well start cold but won't when hot.

[mrv8outboard]

Also with a heat issue you could have a hydro lock situation caused either by fuel leak down into the cylinders (carburetor boiling over/injector leak down) or a coolant leak into the cylinders.