LPW2/4 12V starter suggestion

Hello Guys, I was wondering if anyone out there has repurposed an LPW2 from an 802A for a 12V application and if so, what did you use for a starter?
My 11 year old son took one of my spare motors and swapped it into his JD 425 tractor, because it was there..... I guess....
Due to a lack of room for 2 batteries he wants to convert the motor to 12V accessories.
The original starters are CW rotation with a 10T gear. If I search for a 12V LPW starter I find 11T starters, assumingly because they are used in an application with a different bellhousing and/or flywheel.
Note: he is using the original MEP-802A flywheel and bellhousing.

I found this Onan DL3 starter that looks like it may work. 10T CW rotation.


but was curious if anyone has already done a similar swap and knows of the correct starter?
I will also be needing a 12V alternator if anyone has an idea as to what would fit?

Ray70 said:

...My 11 year old son took one of my spare motors and swapped it into his JD 425 tractor, because it was there..... I guess....
Due to a lack of room for 2 batteries he wants to convert the motor to 12V accessories.

Click to expand...

Not to distract from your question, but good grief...my how times have changed! When I was 11 yrs old I was probably watching Bonanza or outside riding my bicycle!

Your son must have a really good role model to dive into such endeavors at such a young age!

Anyway, carry on with the quest for answers to your questions.

Thank you, he is definitely an exception from the norm for his age. He has built a go kart, resurrected 3 or more old riding mowers, he operates my backhoe.... often loading and unloading generators for me. Now he wants his JD 425 to be diesel powered for no practical reason other than the cool factor.
He welds, uses the milling machine and Lathe, all kinds of stuff he probably shouldn't do at his age.
He's doing school remotely and his screen saver on his Chromebook is a pair of M923A2's ( he grabbed the image off the internet and mad it his screensaver with nothing from me )
However, there is one thing he can't ( won't ) do... CLEAN UP HIS MESS of tools
When I was his age I was probably watching cartoons and riding a bicycle. I don't think I was allowed to tough the lawn mower or any other power tools yet.

Get him his own tools. That was the only way I could control the same problem. THEN, when you find them laying around, hold them for ransom.

Dad was a machinist. When I turned 10 he told me it was time I learned to weld. The 70's were a crazy time.

He started me on a acetylene torch with a brazing rod. From there it was stick welding with a Lincoln 225 AC machine.

I didn't follow in his footsteps to be a machinist but I am very thankful for the skills he encouraged me to develop.

Quick idea on the alternator, you could easily toss a GM 1 wire alternator on there, it’s a little excessive in amperage capacity for the application BUTTTT would give the ability to add lots of lighting for night cutting


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In a completely different direction... why not swap the fuel pump to a 12V version, retain a single battery as stock for any lights, etc... and manually actuate the fuel shutoff solenoid by cable? Mount a remote NATO slave plug on the frame with a HD toggle to open and close the circuit for starting purposes? Its a Frankenstein... but it could be fun.

Funny, the first thing I mentioned to my son was a 1 wire GM alternator...
After talking to a few folks it seems I may have to stay with the 24V system and find room for a couple small batteries.
I hear that the best route is to swap the flywheel bellhousing and starter to the civilian models.... but It will be much cheaper to just leave it as 24V.
I'll just pluck 12V off 1 battery and power the starter off both.
He is using the stock "In tank" 12V fuel pump and the fuel shut off will indeed be cable operated ( no need to spend $200 on a solenoid )
All I would need to buy is a 24V alternator since I don't have a spare.
The up side is we can always use his tractor as a temporary parts donor if one of the generators goes down!

I might have a nonfunctioning core if you wanted to send it out to be rewound/reworked. I can check later if interested.

what about the solution for the mep831a 24v aircraft battery replacemnet - 2 x 20 or 28ah sla or agm batteries?

Yes, The 2x AGM batteries is probably the route we are going to take. We still need 12V for the rest of the tractor's electrical and I have previously use 2 18/21AH batteries ( emergency lighting and jump pack batteries ) to power my 831 instead of the costly 24V battery that it requires and it worked well.
The other possibility would be a pair of small motorcycle batteries due to the limited available space due to the LPW2 being a bit bigger than the original V twin gas motor.
I would say keeping the starter and charging system 24V and simply splitting the 12V and 24V power accordingly will be the best and cheapest solution.

If the 12volt loads aren't too big you could used a 24v to 12v buck converter to power the 12v loads. That way you'll be pulling power from both batteries and will help keep them balanced.
Buck converters are very inexpensive.

I'll second that, you don't want to pull 12V off one battery if the system is being charged by 24V only. A converter is probably the simplest, cheapest option all things considered.

Ok, I will check into that... Thanks!