Wiring Question
 

I have been trying to get the charging system to work on my 149. Replaced the V/R after doing the S/G test found here and decided to replace the the V/R from a source mentioned here (DB Electrical I think it was). Anyway I get the new V/R on and still get nothing showing on the ammeter, engine sounds like it’s loading a little after it cranks but don’t want to run it too long if somethings not right.

Lots of information on here about these issues and I feel like I have read it all and still no luck.

Out of ideas I thought I would try to polarize the V/R just for the heck of it. When I jumped between the Bat and Gen terminals the engine started to turn over. Nothing I have read says that’s supposed to happen. Would that indicate I have a wiring issue somewhere?

I removed, disassembled and cleaned the S/G, removed and cleaned all the grounds and other odds and ends but nothing else electrical.

I have ohmed the three wires from the V/R as some suggested and the Bat is getting 12v with key off. Only other thing odd is with engine running my voltmeter is all over the place when I put it on the battery. With the engine off it’s a steady 12.5 or so volts.

Any ideas would be appreciated before I rip into the wire harness.

Jumping between the bat and gen terminal will crank the starter.

Did you try grounding the field coil and measuring voltage at the starter/generator with the engine running?

I am confused. Do you have a charging, starting, and/or both issue(s)..??

:Huh:

Oh man.. I would not suggest you rip into anything just yet. Need to slow things down and start over. By start over i mean, put the old VR back in and troubleshoot this thing from the beginning.

Yes. But for what ever reason with the engine running I can’t get a solid reading. Volt meter just dances, roughly 14-.5 volts.

Also the ammeter doesn’t move when I do this. Engine does load up.

Just charging. It cranks fine but the gauge stays on 0.

The rubber mounts have rotted and the old one will not mount to the fender, does that effect its operation? Also pretty sure it’s sat full of water by the looks of the inside. As far as gauge reading, volt meter and operation of the tractor I can’t tell any difference between the old and new V/R.

I think I have read here that some aftermarket VR's are not wired the same as original. Have you verified that the wires are connected to appropriate terminals?

If they are connected correctly the next thing to so would be to GROUND the F terminal temporarily with the engine running. Check voltage. If the voltage rises with power on the F terminal then the VR is bad or not connected properly.

It works the opposite of that, coop. The voltage regulator grounds the F coil to increase the output of the generator.

Voltage might bounce around a lot if you’ve got a dinked up starter/generator though. Could be that you’re not getting current out of some of the windings so as the commutator rotates past the brushes you get some sections that are good and some that aren’t. An o scope would show that but probably not a simple multimeter. Also I would think that starting might be rough if that was the case.

If it’s putting out voltage even part of the time, I think it should probably charge though. Have you measured the output voltage at the bat terminal with the engine running?

lol.. your right.. still half asleep here.. my apologies

meant to say ground the terminal