106 No Charge

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trice
Posts: 6
Joined: Sun Apr 26, 2015 5:19 am
First and Last Name: Thomas Rice
Location: Sunbury, OH

106 No Charge

Post by trice »

Followed the no charge trouble shooting FAQ for a 106 w/starter-generator. When SG field post jumped to case/frame, RPM dropped. With engine running, field post jumped to frame and RPM dropped, placed voltmeter on battery terminals hoping to see an elevated volt reading from the charge but didn't. This doesn't seem right, any thoughts?

According to the trouble shooting FAQ, If the RPM drops, SG is good, regulator is faulty. Had a hunch my issue was the regulator so already had an IH-545130-R93 from PartsTree.

Installation instructions (IN THE BOX):

1. Turn ignition switch OFF. Disconnect the battery ground cable.
2. R/R VR reusing original hardware. Attach wires in the same relative position as the original unit.

(In my case, the new regulator was nearly identical to the one on my 106 which looks old and most likely original. The only difference noted on the exterior were the new regulator used rivets to fasten the suspension mounts and the old one used nuts and bolts. I haven't looked inside the new one.)

3. Reconnect the battery ground cable. Before starting the engine, polarize the regulator using these steps.
a. Using a spare piece of jumper wire, momentarily (2 seconds) touch the wire to both the (BAT) terminal and the (GEN) terminal or (ARM) terminal of the regulator.
b. DO NOT touch the jumper wire to the field (FLD) terminal.
c. There may be a small spark. There is no danger.
4. Start engine and test the charging system for proper operation.

I did this on the original regulator (BEFORE reading the FAQ) thinking that to get a charge MAYBE all I needed to do was polarize the old regulator. I was quite surprised when the spark was quite large and the SG started to turn the motor!

Here are my questions:

1.Why didnt I see elevated voltage at the battery terminals with the old regulator still installed and the SG field post jumped to the frame with the RPM dropped in the troubleshoot step?
2. I have installed the new regulator but HAVE NOT started the engine yet or completed step 3a. Do I need to complete 3a and jump 12v from BATT terminal to the GEN/ARM terminal to attain proper charging ops?
3. My tractor's wiring harness is missing the neutral safety switch wiring and switch. Also my harness has a green thicker gauge wire running from the back of the ignition to the BATT terminal of the VR thats not depicted on the 106 start wiring diagram. When I installed the new VR I left this green wire off the BATT VR terminal but the start position on the key switch wouldn't activate the SG. When I put the green wire back on the BATT terminal, I can activate the SG by bumping the start position on the ignition. The other wire on the BATT terminal of the VR is always hot (with the battery connected) and runs to the Discharge/Charge gauge as pictured on the 106 starting wiring diagram. Is the green wire supposed to be there or is a modification?
4. Any tips on how to "test the charging system for proper operation"?

I know this is a long post… Thank you for reading it and any feedback/thoughts given.

Klapatta
Posts: 1352
Joined: Mon Sep 06, 2010 2:25 pm
First and Last Name: Kenneth LaPatta
Location: Rockingham VT.

Re: 106 No Charge

Post by Klapatta »

I'd begin by ditching your old wire harness and getting a new replacement from Dave or elsewhere.
That series has a reputation of the harnesses atomizing into dust after 35 years or so. Folks make repairs on them but to me that is simply not worth the expense, time, or effort. A replacement harness uses the durable plastic covered wire and not that old school rubberized cloth covered stuff and also it will fit in like a glove when your done. Replacing the harness becomes very cost effective in the end. ! Make sure all your ground connections are clean and bright. There is no polarizing procedure involved. The generator self polarizes each time the key is turned to start position. The neutral safety switch can be bypassed by forcing a prong style 30 amp fuse into the two orange lead socket. Defective key switches are not unheard of so keep that under consideration while trouble shooting.
There are many brands of voltage regulators out there for that application and the terminal to wire mounting points DO vary greatly. So make your connections accordingly. I prefer the Napa VR896.

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trice
Posts: 6
Joined: Sun Apr 26, 2015 5:19 am
First and Last Name: Thomas Rice
Location: Sunbury, OH

Re: 106 No Charge

Post by trice »

Thanks Klapatta. New harness from Dave on the way.

I performed the polarization step in the VR instructions this morning. After doing so, I started the engine and the system began charging. With the engine running voltage at the battery is between 14.1-14.5v.

The new harness will go on as soon as I get it.

DaveKamp
Posts: 555
Joined: Mon Sep 06, 2010 10:19 am
First and Last Name: Dave Kamp
Location: LeClaire, Ia

Re: 106 No Charge

Post by DaveKamp »

The whole 'polarization' situation...

The starter-generator and mechanical regulator are viewed at as 'crude' by people who don't understand the technology... since these have NO solid-state devices, they CAN become entirely polarity-identity-flexible.

It's an electromagnet, so Why would it matter?? Simple--- when you apply a direct current to a coil, and that coil is wrapped around an iron bar, the iron bar becomes a magnet. When you turn that current OFF, the magnetic force ALMOST COMPLETELY goes away...

...almost...

Some 'sticks around'... it is residue... because you made it a magnet, it kinda wants to stay all molecularly-aligned to that direction.

It will tend to want to stay that way, which means the contacts will WANT to trip in a current flow of one direction, but not so much in the other direction.

Same thing happens to the polepieces of a DC generator.

If you leave them sit dead for a long time, that residual magnetism eventually fades away... and this is why you need to 'flash' the field on a new, or long-sitting system to wake it up.

And if you happen to be working on a generator that will run, but not generate, put a modest resistive load (like an incandescent bulb or a resistive heater) on it, and stick a big magnet on the side of it somewhere... leave it there 'till the engine grunts and the light comes on... then pull it off, and let it run and power that light or heater for an hour, to 'recover' the residual. The magnet creates a temporary magnetic field to 'boot-strap' the generator into operation, at which point, it rebuilds it's own field. Works on starter-generators, too... but usually the S/G will rebuild it's residual on it's own, because we're shoving high current through it to roll over the K-single.
Yes, I'm a Mad Scientist... but I'm usually happy, even when things ain't goin right.

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