B7100 HST-E Regulator/Rectifier Crossmatch

[jparasho]

I am having problems finding out if there is another kubota rectifier/regulator that will work with my B7100 HST-E 1980 tractor. The origional part #is 15372-64602. I am trying to find out if a Kubota part # 66611-55250 or #67211-55230 will be compatable with this tractor. Also if the rectifier is bad would you still be able to read voltage out of the dymo. I had the dymo replaced when i had the head replaced due to a crack in it. Battery will not stay charged for more than a few cuttings. I am new at the workings of the dymo and regulator on this Kubota. Kubota mechanic says that if the regulator is bad i will not get a reading on the dymo. Any help would be appreciated. Thanks Jim

 

[j t huskins]

I just purchased a new rectifier for my 1978 B7100 last week and the PN is H6720-55200. It is smaller than the original and came with two different mounting brackets to adapt it to my tractor. It has the 4 wires as needed but the red charge and black ground are together in a 2 pole connector which I will have to change to plug into my individual wire connectors. My Dynamo shows 20+ AC volts if I check between the two blue wires coming from the Dynamo. If I check in line on each individual blue wire it shows 6+- AC volts. My WSM is difficult to see the test diagram so I'm not sure which way is correct. I only get 1 volt DC out of the rectifier to the battery so I chose to start with the rectifier first.

 

[ibnxe]

I can't answer your question about the cross referencing of the regulators, but I would expect that they are basically the same except for the plug connections. 20 volts AC sounds about right for the output of the dynamo. The regulator actually performs two functions. It rectifies the AC and also controls the maximum voltage sent to the battery. DC to the battery should be above 13 VDC.
The Kubota mechanic's comment is not correct. The dynamo will work all by itself. It is merely a coil of wire in a moving permanent magnetic field.

 

[jparasho]

Thanks for all the help. I guess I will have to try and test the dyno again and try to figure out which way to go from there. Can anyone think of a reason I might be getting a low reading out of the dyno? From everything I read they dont seem to go bad very often. thanks Jim

 

[Rockon70]

I just purchased a new rectifier for my 1978 B7100 last week and the PN is H6720-55200. It is smaller than the original and came with two different mounting brackets to adapt it to my tractor. It has the 4 wires as needed but the red charge and black ground are together in a 2 pole connector which I will have to change to plug into my individual wire connectors. My Dynamo shows 20+ AC volts if I check between the two blue wires coming from the Dynamo. If I check in line on each individual blue wire it shows 6+- AC volts. My WSM is difficult to see the test diagram so I'm not sure which way is correct. I only get 1 volt DC out of the rectifier to the battery so I chose to start with the rectifier first.

I have the new rectifier for my B7100, so I need to change the two pole plug on the new one and get another end for the Red to Red connection? My black ground went to the mounting bolts. Thanks