Allis-Chalmers 808 GTII info-PLEASE HELP!

I have an Allis Chalmers 808 GTII from the early 80's,with an 8 HP Briggs & stratton engine,and a three-speed gear driven transaxle(not hydrostatic).How can I identify the make and model of the trans-where would there be some kind of number on it? I want to use it as an ATV since I no longer mow with it,and I would like to increase the speed.Anyone have any experience,advice or information on this would be helpful.

 

A riding lawn mower designed with no suspension and low speed does not seem like a good candidate for an ATV conversion in my opinion.

 

Welcome to the forums.

I agree. Tractors aren't built to withstand ATV duty not to mention no needed suspension.
Looks like that tractor uses Simplicity parts.
tractor parts
tractor data

 

Swap the engine pulley with the transmission pulley and put taller wheels on the back would be a start. Have a good one. Geo

 

Yep, if you want to go faster, put a bigger pulley on the engine, smaller on the transmission. You won't be able to swap them directly because of shaft diameter differences though. The transmission, if H-pattern shift, is probably an old Foote transmission and they hold up pretty well compared to most modern transmissions. I understand they had forged gears instead of cast, and they use oil instead of grease. I built a mower with a foote transmission that would run 50 mph and do donuts and catwalk on the rear wheels.

 

If it helps,the transmission doesn't look like the modern types.The gearbox is kinda oblong and is vertical,(looks like an old Ford model T diff),and sits off-center,with the output shaft coming out the side and a 9" pulley on it.what about overspinning the shaft on the tranny using a different pulley? I thought these could take only 2000 rpm on the input

 

Make sure to use some money for the ATV conversion to upgrade your medical and life insurances if you plan on going anything near 50 mph on a suspension designed for 10mph.

 

You have a gearbox instead of a transaxle? If so, you probably don't have what I was describing.

I wouldn't count on ANY suspension, there isn't any. 50 mph on a lawnmower isn't for the faint of heart but 15 is pretty tame and still a thrill. Doing donuts burning rubber on an asphalt parking lot on a riding lawn mower is something people remember though, especially the driver lol. That mower has been mud bogging, raced and beat 4-wheelers, and talked about locally by many lol. You either drive it or watch and remember the guy that did. The guy in the pic was my helper. He wanted to build the mower. When I drove it, I could pin the inside front wheel to one spot and swing the rear around and around smoking the tires... on asphalt.

 

I'm not lookingb to do 50mph! I just want it to go about 15-20 mph as a runner on smooth pavement.This is what the tranny looks like-I need to know what kind/make it is....

 

I'm not familiar with that unit. But still, a bigger pulley on the engine and smaller on the transmission will result in more speed. 50mph is not recommended lol. Well maybe, but not officially.

 

I'm only planning to do 20,maybe 25-30 on the outside.Just using it as a runner around the neighborhood in my small town-slow,but still have to go fast enough to keep semi-up with local traffic.People around here do it all the time on their ATV's-why can't I,on practically the same thing? .I already have it,no point spending $3000,000 on a used ATV(look on craigslist-BOY are they pricey!) when I already have 4 wheels and a motor sitting in my garage that I'm no longer using as a mower.Far cheaper than driving my 6400# 3/4 ton chassis Dodge Mark III just to get groceries. $5 to go one mile.The same $5 will go farther than that on a tractor.

 

You're not going to be able to licence & insure that lawn mower to be on the highway.

ATV's now days can be licenced for the highway.

You're likely to end up with a ticket & depending on the officer that stops you, a wrecker bill to tow it back home. I'm just giving you FYI. I don't know anything about your neighborhood or the law enforcement there, but I can absolutely say that mower is not legal for the highway.

 

ATVs are made to do those speeds. Mowers aren't. You'll have bearings and gears going bad and the transmission won't last doing this for long. But it's fun for a project and a little while. Oh, and brakes on a mower are made to stop a 6 mph mower, not a 30 mph mower. They are tiny.