Structures Allis 620

something doesn't look right about the front of the crankshaft, looks short to me

What is that extra gauge in the dash?  Not the ammeter...

Looks like a decent unit.  It appears someone removed the front clutch to fit that extra large battery on there.

Nice lookin' unit! Dave & Dan are right, what's up wit' the short crank? Hmmmm... wonder if that was machined off. Looks to clean of a cut to be homemade to be done in the chassis. Strange. As Dan mentioned, that's gonna be tough to run a snowblower, loader, or plow off the front with that short crankshaft. Might have to improvise when the time comes, but still a nice unit. Good luck with it.......
Steve@B&B

Somebody previously put an oil pressure gauge at the top.  It's not hooked up though.  I figured the front shaft was shorter because it used a clutch style pulley.  That battery is actually turned sideways is why it looks so big.  It's one of those new little lawn mower batteries.

Is the engine out of a generator? I think they had short tapered shafts.

Appreciate your guys help.  I think it is a generator engine or a cck engine?  Not sure.  There's no markings on it, but some of the black paint has scratched off and it appears to be that onan green color.  Guess it's been re-powered.  Here's some more pics.

Talk about Green paint. My 620 had a Lime Green paint on the inside of a couple of the engine cover shields. They were Black on the outside, but Lime Green on the inside of a couple. Nasty lookin' color..   

Mine has a plain black steering wheel center cap. Can I get an Allis Chalmers logo one, for cheap?

Look at how high that seat is, look at the 2.5" clearance to the hump in transmission cover. Only about 1/4" clearance on mine. I gave up
trying to remove the cover, after I scratched it. How many different seats are on these things.

Something looks different with the air cleaner.

I have a good belly mower and front clutch. BUT I would rather use
the Woods RM59CO cat 0 3pt mower. The belly mower is in the way
for tractor like operations (plowing,disking etc.). Yikes, cost of
clutch, crankshaft and mower. I think the Onan was used in a
Sears Suburban model. I don't know about that crankshaft end.
Ask an Onan expert if they ever seen that, perhaps an Ebay seller.

Does AGCO sell parts for the 620. I notice they do not have a parts manual online. Can a genuine AGCO dealer see the parts book?

Did anyone on this forum work at Simplicity when they made these
tractors? Have any stories to tell?

If I had the time talent and money and wanted a big project,this is how I would re-do the 620-
Different engine 3cy diesel or gas.
Larger gas tank. Fuel gage on dash.
Foot operated hydrostat controls.
Bigger better transmission oil cooler.
Tractor like 3pt lift operating lever with position control.
Power steering like on the JD318.
Two remotes up front for snow blade.
540 rpm PTO- I think this would be a toughie. 3.7 times lower RPM=3.7 times greater torque and loading forces. Looking at the parts book pictures I see a drive shaft with gear driving an idler gear driving the pto shaft. I have no sense of space available in there for new gearing arrangement. Does anyone think this is a possibility?

What was the price of a 1975 720 with rear PTO and 60" mower?

I think Allen is dead on with AC painting over the Nasty Green Onan color. Just starting to get my CCKB engine back together. I'll have to take a few pics of it as it goes back together. Got the new front tires for it and mounted them up at work at lunchtime. Tossed them back on to get it rolling again. I wanted to have this project up and running before the cold weather sets in. Want to use the loader for snow removal and around the property next season. Got the subframe for the loader bolted to the bottom of the Tractor also. Its gettin' there, but not quick enough. To darn busy with my full time job and our business. And with the rain we were getting for a while, the mowing never ends! LOL!