Alternator choice

[ruschman]

We are working on a to20 conversion. We ran into a problem with this statement "replacement Z-120 blocks were cast from Z-129 patterns. The result is two untapped bosses on the block behind the generator which prevent the alternator from mounting and this will not work" and are now confused. What did you folks use as an alternative? Any comments or solutions are welcomed. Is it mounting brackets or size of the unit that is the problem?

 

[Mad Farmer]

(quoted from post at 14:33:12 12/01/23) We are working on a to20 conversion. We ran into a problem with this statement "replacement Z-120 blocks were cast from Z-129 patterns. The result is two untapped bosses on the block behind the generator which prevent the alternator from mounting and this will not work" and are now confused. What did you folks use as an alternative? Any comments or solutions are welcomed. Is it mounting brackets or size of the unit that is the problem?

The TO-20 I have, had the motor replaced with a TO-30/Z-129 engine before I got it. It was also already converted with a 3-wire Delco alternator. I'll try to get a picture of the way it's mounted tomorrow ( dark and raining right now).

The 1-wire Delcos should mount the same and simplifies wiring.

 

[ruschman]

[I wonder if that means if I look for to30 alternator kit it would fit on our 20?

 

[Jim L WA]

Hi ruschman, I have a TO-20 with an alternator. It was already on it when I bought it, but it looks like it used the same mounting holes as the original generator. Here is a photo of it.

 

[Tom H.]

If you can, find a one wire alternator positive ground. Just to keep it simple. Ive put these on my TO30 and TO35. My 30 has an 8 volt
battery and alternator.



Tom

 

[ruschman]

Tom, it's not the wiring or the voltage. It is finding the brackets to fit our block. Still trying to determine if ours is like the one pictured above.



Tom[/quote]

 

[Mad Farmer]

Still raining here but I found a picture of the bracket that mounts to the block, looks homemade. Still need a better picture of the rest of the bottom mount and adjustable mount/arm.

The adjustable mount also seems to be fabricated, maybe from the original? They added a 2nd piece of flat stock and bolted that together to make the adjustable arm.

I believe the alternator is a 10SI

Looking over your original post you seem concerned about having a "replacement block" TO-20 from TO-30 casting. What makes you think it's a replacement block? Look up the ser #

This post was edited by Mad Farmer on 12/03/2023 at 08:45 am.

 

[ruschman]

Sorry for the confusion, Farmer. I was using the wording of the alternator vendors. They called it a replacement block. My mistake was thinking the rep block was from a to30. I was wrong there also. What it comes down to is that it appears no one is producing a bracket to fit the "replacement" block. I appreciate any photos that will help us fabricate a new one.