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Cletrac Tractor Discussion => HG, OC-3, OC-4 & General => Topic started by: Jethrow on May 23, 2011, 07:19:38 PM

Title: 12SI Alternator Conversion
Post by: Jethrow on May 23, 2011, 07:19:38 PM
Wanting to add a small ATV winch to my OC3-42 for some light logging, it was time for an alternator conversion.  I decided on the Delco Remy 12SI 3 wire model for the low speed excitation and the availability of a compatible pully.  My Ford NAA and IH 656 both have 10SI's so they're familar.

I had no idea in advance how to mount it so I took a chance on a 'C' shaped mount for a Chevy from eBay knowing the bolt pattern of the 12 SI to be 6.6" across.  Using the 'C' bracket, a section of the mounting bracket supplied with the alternator and two small bushing I was able to line up the pulleys within tolerance.  I replaced the HF link belt with an appropriate fan belt.

Not fond of the starter button with kids in the barn, I added a starter solenoid and key ignition switch.  The switch also provides the "accessory"  12V for a "not charging" indicator lamp and the excite signal to the alternator  I also plan to replace the magneto kill switch with a relay so everything goes on and off from the ignition switch. 

So far I am happy with the conversion. There is a slight clearance issue with the oil filler cap but I can live with it.

Hope this helps someone planing a similar converison.

Jethrow
Title: Re: 12SI Alternator Conversion
Post by: hotratz on May 24, 2011, 02:48:49 AM
Thumbs up! I didn't realize those C-brackets were available commercially. When I started my conversion using a 10SI the bracket that I ended up fabricating looks a lot like that one, funny. I still have it and the rest of the stuff I made for a 10SI conversion.