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Kohler M20

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The M series was the updated KT series, which for the most part, a much better engine. Knocking when running might be a carbon build up in one head. I have had some Briggs come in that way. My 2 cents.

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I run one in my 917H. It is an improved KT like noted above, oil filter full pressure lube, electronic ignition. Smooth running.

But like the KT has limited amount of oil in the system.

Kohler rebuild parts are real pricey.

At $300 I would swallow hard if it is knocking. Any chance it was run low on oil?

No noise and it would be a buy for me.

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No idea what the reason is Greg, if it was run low or not.

PO said it started knocking badly so he shut it down and hasn't touched it since.

Not too worried about the price, that was a hook to get you guys interested. LOL

It is still attached and comes with tractor, deck, snow plow and loader.:o:O

Just trying to figure out if it's repair or replace.....

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The Magnums were used in the early SS's, before they switched to the Commands. They are quite powerful motors, but definitely do not run as smooth as the Commands.

Parts are fairly available through eBay, etc, since the motor was used on several different brand tractors. But - but - the parts can get pretty pricey. Do some looking on eBay at Kohler M20 and Magnum 20 and you'll see what I mean.

I had one that I took out of an old SS because it was cheaper to upgrade to a Command than to buy the parts to rebuild the Magnum (Thanks to a club member giving me the brother-in-law price on a beautiful low-hour Command). A fan of another brand saw the Magnum sitting in my garage and offered more than I would have expected for it (despite me bench running it for him to show him the problems with it), because he was convinced that he could make decent $ on it by parting it out.

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Depends on the problem, the oversized pistons are expensive, but most of the other parts are very reasonable.

A very good engine, just built one last fall with parts from several other M and KT engines.

So BLT had one possible reason, here is another: I got parts from an M18 engine, that the PO said had a really bad knock. So he replaced the engine, and sold it to someone who needed the crank and cam, I got the cylinders/pistons/heads for free. One cylinder head and top of piston were beat up a little from something in there, but the cylinder and other parts were fine. The crank and rods were good. Probably dropped the screw from the air cleaner plate into the carb throat.

So don't knock a "knock" until you have more info...It could be an easy fix.

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