B2400 Alternator

Gomez · Apr 26, 2015

my b2400 battery light came on yesterday and I also noticed a faint burning rubber smell. Took the alternator off and tried turning it by hand. It would turn in one direction easier than in the other. Put it back and started it up. Alternator spin for about a minute then seized. Looking online for a replacement, there's a broad range, from $75-$200.

Another thing I came across during my search, I thought these were alternators, not dynamos. I saw one comment stating if the unit spins freely, it's an alternator. If it has a clunking feeling, it's a dynamo. Mine has the clunking feeling when it can turn (like a stepper motor), of about 8 steps per rev. Also, it has 2 wires which to me indicates an alternator.

I'm leary about the low price replacements.

Any thoughts?

Thanks

brain55 · Apr 26, 2015

Gomez said:
my b2400 battery light came on yesterday and I also noticed a faint burning rubber smell. Took the alternator off and tried turning it by hand. It would turn in one direction easier than in the other. Put it back and started it up. Alternator spin for about a minute then seized. Looking online for a replacement, there's a broad range, from $75-$200.

Another thing I came across during my search, I thought these were alternators, not dynamos. I saw one comment stating if the unit spins freely, it's an alternator. If it has a clunking feeling, it's a dynamo. Mine has the clunking feeling when it can turn (like a stepper motor), of about 8 steps per rev. Also, it has 2 wires which to me indicates an alternator.

I'm leary about the low price replacements.

Any thoughts?

Thanks

Post a pic I'll tell you immediately what you have. A dynamo is going to look like a solid shell. An alternator will look like what you'd have on your car. More open and vented for cooling. If what you have has two blue or grey wires with bullet connectors it's a dynamo.

Brian

Gomez · Apr 27, 2015

Brian,

Thanks, I attached a photo of the unit like on my tractor (except mine is painted).
It's the shell, not vented.

Is it better to replace in-kind or should I get an alternator?

Sodo · Apr 27, 2015

My battery light is on too (Kubota B2710), have to put the tractor on a charger to be able to start it.

At the battery there is no voltage difference running or not. My dynamo looks same as the 14Amp unit Gomez' posted and it's painted Kubota gray. It has a two wire output, both light blue, with bullet connectors. They were corroded pretty bad but I cleaned them up with hopes that was the problem, but still no charge voltage at the battery. I did not put an voltmeter across them, was busy with other stuff. I intended to test it later but didn't.

Is there a quick dynamo test that I can do to determine whether to order a new unit? Is the output of the dynamo AC or DC and what values are expected?

SeymourBota · Apr 27, 2015

I did the alternator upgrade on my 2410 and it was well worth it.

Easy enough to replace- you also get a new mounting bracket and belt. Between that and my battery maintainer, I get many years from my batteries.