12 volt starter conversion?

Engineer Cub

New member
Good Morning all. I have a 1951 Cub that needs a new starter. I disassembled the original 6 volt starter and did the continuity and ohm tests on the armature and determined it was bad. The field coils also tested bad and one of those was missing the insulated wrap. I have converted the tractor to a 12 volt charging system and wanted to know if I could use a later model 12-volt cub starter on it? It is my understanding that the water inlet on the later tractors had a relieved area in the casting that provided clearance for the larger, 12 volt starter. If I replace my current water inlet with this one, should I be able to run the 12 volt starter?

If any of you have done this, I would appreciate your feedback and photos if available. Also, where did you purchase your starter from and what was the part number? In searching these part numbers, it appears that some were superseded by other part numbers and I want to be sure that I order the correct starter the first time.
 

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Along with the water inlet, the engine block was also modified to give more clearance for the 12-volt starter. Whether the 12-volt starter can be used with the earlier engine blocks has been reported as a somewhat hit-or-miss situation. It may work, depending on Individual variations in the block casting. The 6-volt starters seem to hold up on 12-volt conversions. So just getting a replacement 6-volt starter is the least complicated fix.
 
Welcome to the Forum. If you can find a shop that rebuilds starters, maybe you can get yours repaired. You can probably find some recommendations by posting that you want some contacts. Other forum posters have been successful by doing that. JMHO Stan
 
I wanted to do this as well, because my starter was bad, and I had the elbow and the 12 volt starter.
The parts are still laying on the bench in the shop, two or three years later, as I haven't taken time to make the swap, or at least try. It seems like a good conversion, especially for a guy like me that already has all the parts to do it.
 
I wanted to do this as well, because my starter was bad, and I had the elbow and the 12 volt starter.
The parts are still laying on the bench in the shop, two or three years later, as I haven't taken time to make the swap, or at least try. It seems like a good conversion, especially for a guy like me that already has all the parts to do it.
@69ranger I would be very interested to see if this will bolt up on your tractor. When you get around to it, please let me know what you find out.
 
Will do. I am so behind on my "have to do" work, that it will probably be this winter before I get anything done.
 
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