Newer M-F question about alt.

[Levi Keech]

we have a 1992 M-F 3690 that had to have a new alternater put on it last fall when we were doing custom baling for customers. Well, since the tractor is canadian, it had a forgein alternator on it so we took it to the local Deere dealer where they put a Delco-Remy on it and converted it over. Well here's the problem, the tach isn't hooked up and when you do hook the wire up, it pegs out, and because of this the hour meter does not work either. A machanic at Deere sed we need to get a resistor for it to cut down the voltage. But he didn say what type of resistor, is it just a regular ballast resistor that you put on rite before the coil on older tractors? How many types of resistors are there?

 

[souNdguy]

There are as many resistors as .. well.. enough to fill some books.

Are yuo sure your new alternator has the correct tach sending unit for your MF tach?

what's the alt model number?

soundguy

 

[Bob M]

Levi - There's literally millions of resistor types. That issue aside it doesn't sound like your Deere dealer knows what he's talking about in the first place!

Alternator-driven electronic tachs like on your MF tractor use a separate terminal on the alternator that taps an AC signal voltage directly from one of the stator windings.

A good alternator shop should be able to modify your Delco alternator to provide the tach signal output. This of course presumes your previous unsuccessful hookup did not fry the tach/hour meter.

 

[Levi Keech]

I don't know the model number, all I know is that deere had better not stop selling their toys and crap because they wouldn make it repairing actual equipment. Bob would agree with my uncle, the mechanic we talked to really didn know what to make of the thing. If thought that if I put a ballast resistor on that that would make it work. If we knew what we did now then we woulda just rebuilt the other one. what do you think if I hooked a ballast resistor on?

 

[Anonymous-0]

Take it in to Ames Auto Electric and have Loren fix it. Problem solved. Ryerson's can't fix anything.

 

[souNdguy]

To be honest.. i think you are stuck.. Some alternators have tach sender on them.. most don't. if this is just a generic 3-wire alternator.. it probably doesn't. You could hang a ballast resistor, a diamond ring, and a license plate from an old desoto on it and you still wouldn't have a tach hookup if it was not designed to be compatible with your tach.

If you had the model number.. we could at lest research what alt you had, and what options it has.

I think you probably should have had the old one rebuilt... ya still got it?

soundguy