1980 C-85 WheelHorse blowing fuse

[Tuneup 1,416]

So, I expect the voltage at the battery also dramatically increases at 2/3 throttle to reflect the increase in current. Suggests the regulator. I was in the same boat - regulator flaky, wiring half melted, ammeter open and coil dead. The previous just removed the fuse - simpler. At least the wires were in the right place. Verify that first and the right ign. switch and replace the regulator, I'm thinking. Never fun.

 

For what it's worth: The Sears one I'm working on - if I repair two of them I get the C-120 and Commando7 for free - had the wrong ignition switch and wrong solenoid. The two remaining black leads - both grounds - were wired to the starter side of the solenoid (+) so he burned out the alternator and shorted his switch to ground each time he tried to start it. Glorious...

[Henry Black 3]

This afternoon I checked the wires to verify they are right and the ignition switch is the right one. I don't believe it has ever been removed until this afternoon. Then I started checking things on the list. I was going to remove the wires from the regulator/rectifier but I could not get them off. I had to remove the regulator and then I found that the plug had melted and the wires were stuck to it. I pried them off of the plug.  The regulator terminal for the b+ was really burned.I had to put a new terminal on the wire to get it reattached and I cleaned the lugs on the regulator with wd40 and a wire brush. There were quite a few spider webs and little bug skeletons on the back of it. I checked the Stator voltage and it was right around 30 volts AC. I hooked the regulator back up after tapeing the wires to insulate them. The ammeter almost immediately dropped down to about 2 or 3 amps. I checked the voltage across the Positive and negative wires and it was reading about 13 volts. I am sure I am getting somewhere now but I'm not sure if I should just replace the regulator or not. Thanks for your help.

[gwest_ca-(File Mod) 10,496]

Sounds like you got it. If you can get the terminals sanded down to bare clean metal a coating of dielectric silicone grease on all of them should be all it needs. This product is available in small tubes and will not conduct current so no chance of it causing a short between circuits. Coat them completely and fill the plug-in connector.

 

Garry 

[Jayzauto 89]

GEvening Henry, I've been jammed up at the shop and haven't checked back...I apologize.  ANY loose connection will cause a voltage drop, which will cause heat and as you've seen, cause melting.  I agree with the regulator diagnosis as the cause of the main problem.  I think for the cost of a replacement and the damage it can cause, a new unit should be installed.  Loose connections will cause the conditions you found, but they can be intermittent also.  So the fact that it appears at this time, to be operating better, unknown damage may be present.  Count me in, on the addition of ground wires from the regulator housing to a solid ground point.  When everything is shiny and new, the regulator ground is sufficient......but shiny and new was a long time ago.  Additional ground wire is a quick and simple insurance policy on a new voltage regulator.  I would definitely LOAD test (or have it tested).... just because the battery starts the tractor, doesn't make it good.  A low, sulfated battery will cause excessive (read HOT) charging and overloading, as well as poor battery connections.  As stated before, just after starting, the recharging will be highest, and slowly drop close to zero as battery recharges, normally in a few minutes (longer if battery or connections are in poor condition).   This will prevent the replacement ammeter from burning up/sticking also.

 

GLuck, Jay