Model 70 Starter Generator dying

[Kelpie]

Hey there,

My S/G has been having trouble starting my tractor for about a year now and now will not turn it over. The battery is good and there is plenty of power to the S/G.

Is this a matter of brushes wearing out? The S/G has never been rebuilt since 1964.

Thx,

[cubfixer]

I have worked on several S/G's (on my 100 and my 124) over the last two years. I would suggest either buy a brand new one off ebay, or take your existing S/G to a generator shop and have them repair it. There is just so much that can be wrong, such as brushes, bearings, armature, field coils, that it will save you time and money to have it replaced or repaired. Just my .02.

[PaulS]

Brushes are a possibility of a s/g slowing down. Bearings could be another issue. There are not many parts inside and there are kits to fix them. The biggest problem is keeping the brushes back far enough to get it back together.

[Kelpie]

I heard that it's better to rebuild than to buy a new one as the new ones are not like the originals. Anyone know of a good shop in Indianapolis that can repair it?

[R Bedell]

Your situation sounds like (A) You have a lack of power going to the S/G through bad battery cables and/or connections, or (B) that there is an issue with the S/G itself.

Personally, I am an advocate of getting the original S/G rebuilt. I have read some, not so good stories, about these $100.00 cheapies from China.

[dale c.]

I'd recommend finding someone near you with a good working used one to try to be sure it fixes your problem. Be careful when loosen/tightening the nuts on the cables, grind a wrench thin enough to fit under the cable on the bottom nut to make sure the post doesn't try to turn. If it turns it will usually crack the insulators on the studs.

[Kelpie]

I did some checking and when I press the starter button I only get about 8 volts to the s/g, but the battery reads 11.9 volts. Could something else be messed up?

[cubby102]

Check all your connections and all grounds. Sounds like something is loose dirty on a contact point

[MBounds]

Kelpie... 1) clean all connections,and 2) buy and install a NEW ground cable ! Btdt!

[Alvy]

Originally Posted by Kelpie

I did some checking and when I press the starter button I only get about 8 volts to the s/g, but the battery reads 11.9 volts. Could something else be messed up?

Do a volt drop test if you have a meter from positive on the battery to gen terminal of s/g. If under load you're at 11.9 at the battery and 8 at the s/g you might be losing it through a bad connection, bad cable, or starter button if the drop is happening on the positive side. You can do a volt drop test on both positive and negative sides individually from beginning to end of each path. Volt drop test should yield .5 volts or less. If you're losing 3.9 volts under load there is an issue. Hope this helps