Allis G Engine

Thank you for those points! I am just starting to consider the idea, and that was really helpful.

try  'googling electric G' you should get  lots of hits as it's a popular conversion. The problems with batteries are 1) initial cost of GOOD quality, HIGH current batteries, yypically 4 identical units. 2) maintenance, weekly if not daily checking of battery electroyte level and charge 3) run time. the bigger(higher amphr rating) the longer they'll run BUT they need a proper charger to get good life out of them. Deep cycle batteries NOT regular car batteries should be used. Think batteries from electric tow motors NOT golf carts for long(6-10 hour) use then remember what you use, you have to replace ! That WILL take a long time and big chargers cost big bucks.
It's one of those 'do your homework' projects, the more you learn the better the choice you can make. You need to consider spare parts and delivery times, also 'options' like maybe 4 walkbehind rototillers instead of one tractor ?
A good gas G engine will probably outlive you and your kids, as long as it gets clean gas, regular oil changes and air filter cleaned.It's already 50-60 years old, something to consider.
Given the choice between electric or diesel, I'd go diesel. Cheaper to buy TWO 10hp engines, install one, other is a 'shelf spare' than a set of batteries and charger. First I'd check the engine though. Do a compression test, is say 125# all across, it's a good tight engine should be reliable. I would however convert to 12 volt battery and small(Denso) alternator. You'll benefit from easier starting, better battery, easy to jump start, easy to add 12v lights(LEDs) and an electric winch. Regular maintence is the key to have any machine be reliable.
Grab a piece of paper, make 3 columns gas-diesel-electric and write down the pros and cons for each,get as much info as you can, ask LOTS of questions,wait a week, then revisit the list and there is no 'right' answer,it's whatever works best for you.
jay

Oh geez...hearing the G costs a lot to rebuild, AND doesn't have sleeves doesn't make me feel very good...Good thing mine runs good yet! 

Thank you everyone.  This is a great forum.  

@diydave

One potential problem with repowering with say a 22HP engine is the increased available torque that could damage 'stuff' like the axle shafts. Having more power may lead the operator to 'give it' and oopsy, it broke.
The factory fresh G engine was about 10HP,something to remember. Also if an electric conversion is done, it's simple to monitor actual torque and 'dial back' power to not break 'stuff'.

Jay