Yes this is my first post and I have a tech q but I need help desperately. I have an 85 F-250 Utility truck. It had a 351W 2V motor in it with a 4 speed manual but the motor was junk so I rebuilt a 90 5.0 roller motor for it. I used the 4 speed manual but had to change the flywheel and balancer. I got a 50 OZ 164 tooth flywheel (the 351W was a 28oz 164 tooth) from a similar year Ford truck and used the 302 balancer. Everything bolted up fine and the truck ran great. It started and ran fine. Im sure I started it at least 6-8 times. All I had to do was put belts on it. A few weeks went by and I got the belts for the truck. I put them on and it wouldnt start. I thought the starter was bad so I replaced it. Put a new one on and it started one time perfectly and no more starting. The solenoid would kick in but not turn the motor over. I took the starter back and got a new one and it wouldnt turn the motor over either. It looks like the teeth on the flywheel are not as far spaced apart as the starter cog teeth. Do you guys think I have a starter problem as far as not the right cog on the starter for the flywheel? I need help ASAP. Thanks

 

First of all, welcome to FTE!

Have you tried taking the belts off and starting it again? Maybe something is siezed on the front of the engine. You could also put a wrench on the harmonic ballancer bolt and see if you can turn the engine over by hand with the belts on.

 

after that check the ground for the solenoid. the mounting tab to the fender is it's ground source, so be sure it's bare metal.

If this ground is dirty the solenoid can still kick over, but once a load is placed across the contacts it will disengage. Alot of times this bad ground is diagnosed as a bad starter and/or a bad solenoid.

Justin