SH gen test

[GordoSD]

What's that test to see if the generator is working? Before the ammeter, vr etc? Strictly the uotput at the gen, not the battery check.
Voltmeter between gen arm post and ground?

Gordo

 

[John T]

The open unloaded voltage of the genny between its ARM post and its case/frame/ground dont tell you all that much, its what voltage it can supply when coupled to a load like a battery that counts more...

Para 5 (click URL below) tells how to determine if non charging is a Generator or a Voltage Regulator problem and the Par 8 Motor Test is a good way to check the generator itself. If shes running and you dead ground the gennys FLD post if the genny itself is okay she ought to go to the max high charge. If she charges fine with a dead grounded FLD post but NOT othewrwise, the problems EITHER the VR is bad,,,,,,or VR isnt well grounded,,, or wires bad from gennys FLD to VR FLD terminal

To see if the entire charging system is working test the Voltage on the battery.

On a 6 volt system with tractor setting there NOT running the voltage should be around 6.3 volts, then when running at fast RPM if the charging system works it should rise to at least 6.5 to 7 and over range or twice those values if a 12 volt system.

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=665110

John T
John Ts troubleshooting Procedure

 

[GordoSD]

Thanks John. But where do I put the probes of my voltmeter to check genny output, and not rely on the ammeter. The ammeter shows a drop (left) when you pull the switch out and does not move to the right but just centers up when you start it. No increased voltage at battery when running. Flat 6.1 Bat term on VR shows 6.1 all the time.
Problems doing all the trouble shooting as the wires are hidden in a master loom, and they are all the same color (yellow braid). So I'll have to rig some long leads for my voltmeter.

Gordo

 

[GordoSD]

OK this afternoon tests. Tractor off, amm needle at +1. Switch out amm at -3. Tractor running back at +1. Wire fron genny field to ground amm shows 20 amps. Checked battery with the 20 amps on the amm and it read 6. So I have two problems? One from gen to v/r and one from v/r to battery?

Gordo

 

[Janicholson]

If it is reading 20+ when the field is grounded (as described above) the gen is fine, the VR is not grounded, or not functioning to ground the field internlly. The bat volts when charging a partially discharged battery might be close to 6 volts or so even if the gen is charging 20 amps. If you ran it for 10 to 15 minutes with it charging 20 amps, I bet the voltage would be in the 7 to 7.2 range or more. VR issues are my bet. JimN

 

[GordoSD]

OK I'll keep plugging. This is the same tractor I wrote about last summer. I figured it was chargeing because I used it for about 5 hours.
I fired it up couple times in the winter, this spring I went out and it just barely turned over.But it did start. Iused it for about an hour. And the next day it was worse so I then knew the ammeter (at 2 amps) was indeed working. and I was not charging. AMazing how long that SH will run on just a full charge from a charger.
Thanks for the help. I have to print anything from YT board in landscape or I only get about 2/3 of the page.(across)


GW