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leeave96

Sovereign Engine Choices

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leeave96
I thought I'd start another thread on engines/re-powering. My Agco Allis 918H (aka Sovereign) has a Kohler Command CH18S-62513, 18 hp engine in it. There are a bunch of 18ish hp engines available, in addition to the above specific one that are more $$$'s and some less. The above engine has a 1-1/8 diameter shaft x 2-7/8 long. Many engines have the 1-1/8 dia shaft, but it might be 4 inches long. Can you get one of these engines (including a CH18) and simply cut the shaft down? Also, unlike my Wheehorse tractors, Simplicity being shaft drive, and the drive shaft attaches to the flywheel side of the engine, are the attachments to the flywheel side of the engine hard to adapt? If I buy a CH18 engine or another CH engine like a CH20 (which I'll get to later), can I simply take the hardware off my old engine and use it to make the drive shaft connection? The engine prices on these Kohler Command engines are all over the place. The CH18S-62513, which was used on the Sovereign is one of the more pricey engines. Northern Tool has a 20 hp Command that says it's for the Sunstar, but otherwise appears to be similar or same as the CH18S and has the same crank dimensions. It is lower cost than the CH18! Here is a link: http://www.northerntool.com/shop/tools/product_200310303_200310303 I'm wondering/thinking that the non-Sovereign specific Command engines might be a direct bolt in replacement, except for hp, crankshaft length and price. Thoughts? Thanks everyone, Bill

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leeave96
Another point I forgot is that I'm hesitant to buy a new engine, but might would consider it if my Wife/Boss was in a charitable mood... sm03 But more likely, I'm looking for a decent used engine. If other Commands would fit-up/bolt-on (or another make engine), then the idea of buying another make tractor for a low price, with a suitable engine transplant potential would make sense. I've had a couple of Sovereign tractors, either whole or in part, slip though my hands in the last couple of months. Problem is - I'm not sure I could bring myself to part out an otherwise OK Simplicity to fix the one I got vs try to restore it too... :p OTOH, if another color tractor came along with a horizontal Command (or other make engine), I could see myself scrapping that tractor out for a engine transplant. I don't see a lot of Simplicity tractors in my neck of the woods, but do see a lot of MTD Cub Cadets for decent prices. Maybe I could sacrifice one of those for my tractor }:) Bill

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jmhusby
that 20hp looks like a good replacement if money isn't an issue. Did read in one of the topics that one of the guys swapped out a Kohler from a Cub Cadet and it bolted right in. Didn't say what model he took it from. Good luck.

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PhanDad
Based on the installation of a 62501 spec Command in my 75th Sovereign (previous owner had just installed it - about 15 to 20 hours mowing), IMO, the problem with "other" spec Commands is many of the cheaper ones don't have the "chopper" screen. For the Sovereign application (mowing), I believe the "chopper" screen is a must since the bottom of the frame is open and grass clipping are sucked up into the cooling fan. Without the "chopper" screen the engine looked like this:






The clippings are long and find lots of places to lodge. The "chopper" screen has finer holes and a cutting blade at the outside edge to chop the clipping into small bits that, hopefully, will pass through the cooling fins. This is the only pic I have of the "chopper" screen:


A second issue is many of the Commands come with the mechanical fuel pump mounted on the valve cover. This pump will interfere with the Sovereign hood. The hood can be bent out too allow the hood to close (as was the case with my 75th). I think the cost of parts (chopper screen kit, blower housing (chopper screen housing is different from standard), and vacuum fuel pump are about $200, so the "savings" for different spec engine can be lost in the conversion. However, if you already have a Command, then you could swap the parts to the new engine and reap the purchase cost savings.

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PhanDad
PS - Any crank length/diameter should be OK, the 62501 spec crank is 1 1/8" diameter and 4" long. It clears the hood "grill screen" with about an inch to spare:


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tractornut
quote:
Originally posted by jmhusby
that 20hp looks like a good replacement if money isn't an issue. Did read in one of the topics that one of the guys swapped out a Kohler from a Cub Cadet and it bolted right in. Didn't say what model he took it from. Good luck.
That may have been me, I'll give you some info on it. I used a Kohler Magnum 18 aka M18 out of a 1991 Cub Cadet model 1861. The driveshaft coupler bolted right up as its just standard Kohler four bolt pattern. What I had to do was drill two holes for the front engine mounts. And of course some very minor wiring work. The next thing you may run into is the oil filter location. If its right off the block on a Magnum it might hit the Sovereign frame. My Cub M18 had the remote oil filter with hoses so I just used it. Otherwise you might have to notch the frame to fit a block mounted oil filter. So if you are looking for what should be a cheaper route depending on how much you can get it for. Look for a 1990's Cub Cadet 18XX series like an 1861 and so on. Those are the ones with the big plastic hood and side covers and with rounded off metal rear fenders. The Cub I used was well worn out but the engine was great. I only paid $100 for the whole tractor.

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