Better charging alternative for Kubota g1900

[Orangecoalroller]

Currently have a g1900 non all wheel steer and extended the front battery tray to fit a optima red top 34-78 battery,only using it to pull stuff around, I built a pull behind scraper/box blade that has a electric over hydraulic motor on it and it will drain the battery fairly quick, I run it with out the deck and was wondering if there is a better alternator that will bolt up were the small factory one is, with some modifications another idea I had was to to use the deck drive shaft under the mower with a pillow block bearing and mount a Chevy alternator under it

 

[dstig1]

I doubt you will find an available upgrade for a mower alternator (prob not even an alternator on something that small & simple). I would start with finding the specs on the one you have and then start looking into parts for other mowers (maybe bigger ones?) to see if you can find something bigger that might still fit. You are almost certainly going to need to fab up your own mount, so consider that, if your skills are not up to it. Same with figuring out and possibly fitting a pulley of the right size.

Another possibility would be a small generator to power it. If the draw is that significant, you might not get enough power to drive that plus the mower from the mower motor.

A lot of "maybes" but some things to think about as you look into it more...

 

[CalG]

Currently have a g1900 non all wheel steer and extended the front battery tray to fit a optima red top 34-78 battery,only using it to pull stuff around, I built a pull behind scraper/box blade that has a electric over hydraulic motor on it and it will drain the battery fairly quick, I run it with out the deck and was wondering if there is a better alternator that will bolt up were the small factory one is, with some modifications another idea I had was to to use the deck drive shaft under the mower with a pillow block bearing and mount a Chevy alternator under it

From a quick scan, the dynamo used on that yard tractor is the same as equipped with any and all of the B series tractors of the time period.
You are in luck!
There is a 45 amp upgrade kit available from Kubota! I just put one on my B2601.
There is a chance that your application will require some mods to the support bracket or the wiring connector, but my guess it's pretty close. 3 cylinder engine and all.

I got the kit for a bit less than $150, but I had to look around for it.

Kubota #B7324 40 Amp High Capacity Alternator Kit.​

 

[Like Tractors]

Currently have a g1900 non all wheel steer and extended the front battery tray to fit a optima red top 34-78 battery,only using it to pull stuff around, I built a pull behind scraper/box blade that has a electric over hydraulic motor on it and it will drain the battery fairly quick, I run it with out the deck and was wondering if there is a better alternator that will bolt up were the small factory one is, with some modifications another idea I had was to to use the deck drive shaft under the mower with a pillow block bearing and mount a Chevy alternator under it

I have upgraded my G5200 with an alternator that is similar to the kit that Kubota offers to upgrade my B2650 from a dynamo to an alternator, I even used the same belt on the G5200. I believe it is a 40 amp nominal alternator, tested output of 54 amps, DB Electrical 400-52014.

 

[BlueKnife]

I have no idea if it's the same alternator, but on my machine, a Kubota R410 with a V1902 engine, the alternator is compatible with the alternator for a Suzuki Samurai, which is far higher output than stock. Wouldn't surprise me if it's the same mount on yours. The biggest issue may be hood clearance.