3930 starting issues

i have a ford 3930 that starts great when cold. when it's been warm and sitting a while i turn the key and nothing happens. no click, grinding or anything. sometimes is turns over on the 2nd try, sometimes on the 10th try. anyone run into this before? thanks for the help.
 
That could be one of a number of things. A simple safety switch going bad or the ignition switch it self or the solenoid going bad. Try a jumper across the solenoid be sure it is out of gear when you do that. If it spins over that way then likely to be a safety switch or the ignition switch. Jump from the small post to the big post from the battery. If it spins that way the solenoid is good.
 
The electrical system on the 30 series are totally different than previous models. Electric fuel shutoff -relays -etc.and there are different variations of these. Better get yourself a wiring diagram.
 
The early 3930 is not that different than previous models... save a couple of points. They use a cube relay (4RD) to control the starter solenoid. This is located in the fuse panel. The key switch and the safety switches control the relay switching. The basic circuit starts at the key, proceeds through the transmission neutral safety switch on the range lever, then proceeds to a micro switch on the PTO lever. In my experience it is rare for the neutral switch or key to fail on these tractors since little current travels the circuit anymore. However, I have seen the PTO switch fail... and that is quickly wired out. If it wasn't already done 25 years ago.
Beyond that, I'd find the relay, pull it out... and then jump the appropriate terminals with a double blade jumper wire. That will rule out all the control circuits provided you have power feeding the relay. Then you know to go directly to the starter. It's really simpler than it sounds...

Rod
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top