Koehler KT Series

[8ntruck]

I'm curious about the dependability of the Kohler KT series engines in the Simplicity and Allis Chalmers applications.  

The KT series 1 engines did not have a stellar reputation in the Wheel Horse applications, with oiling issues and broken rods being more common than desired.  Operating the tractors on hilly terrain seemed to aggravate the issues.  The switch to series 2 KT engines with a full pressure oiling system seemed to solve the problems.

The KT engines were installed in Wheel Horses withe the crank going side to side in the tractor, instead of front to back like the Simplicity and AC tractors.  If the KT engines were not an issue in the Simplicity and AC tractors, I wonder if the mounting direction might have been part of the problem.

[Austin]

The problems were also noted on AC/Simplicities. The engine itself I feel was a great design but without a doubt needed a pressurized crankcase and/or full oiling system. I own an early AC 917 that had a series I KT17 with 1624 hours marked on the original hour meter when the engine basically blew up, without actually blowing up. I probably could've gotten by with new pistons, rods, rings, gaskets, etc. But the cylinders were very rough and the engine was showing many issues from the failed oiling. It has since been upgraded to a Magnum 18hp and its running great.

[Brettw]

The KT Series I had an oil pressurized system, but only to the main bearings.  The Series II added lubrications to the rod bearings too.  The issues with them was not so much the engine itself, it was that the capacity was fairly low, and if the owner didn't keep track of the oil level and maybe operated on steeper angles.  The pumps starved and hence the problems.  Later models added an oil filter which helped with capacity.  Then they added electronic ignition and re-badges them as the Magnum Series.  They did have a few other potential Gremlins, bad governor gears being one of them, but that was few and far between.  Personally, I think they are great engines.  I love the smoothness and the power they produce.  But you do have to take care of them, and just like any engine, air cooled especially, oil is the life blood.  Keep it topped off, change it when it's due and you will get years and years of good service out of most all of them.

[SmilinSam]

The main thing I noticed when I had a KT apart was that the oil pick-ups in the KT's are not centered in the block. So if you are using a Deere, Simplicity, Cub Cadet or other that sits the engine with the jugs sitting out the sides of the tractor and you mow along a steep enough hill with the pick-up on the high side you will starve the engine of oil.  Been there...Done that....

 With the wheel Horses with the jugs in line with the tractor, its going up or down steep hills that is a problem.

[Snojetter]

Sam - which side of the engine is the pick-up offset towards?  I mow my ditches sidehill and have been doing this for years.  The first two passes are at a relatively extreme angle (I have not measured, but would like to).  I feel comfortable doing it and completely stable, but it does require my rear to be planted almost on the fender 😁 Anyway, since the deck is LH discharge and I'm shooting the clippings to the cut side, that puts the RH cylinder to the low side of the incline.  Is that where the pick-up is located?

Regardless, been mowing this way for years with no issue (M18)  and I check the oil level before I start the engine EVERY single time.

[Brettw]

That pick up is only slightly offset as it sits right next to the one half of the engine case.  That case is split in half equally.  However, as you sit on the tractor it is set right at the joining edge of the right case member.  In reality, I don't think it's even an inch off center.  And if that inch offset is causing oil starvation on a sidehill, I would think you are either really low on oil, or you got some guy hangin' out on a sidecar to keep you from rolling over.  This coming from an ol' fender sitter from way back.........😉

 

 

[GWGAllisfan]

Somebody here a couple of years ago told me the best choice was" Downhill and to the right", although I do have a couple of  fairly steep uphill strips I have to mow.

I think keeping the oil full is the main prevention technique.

[GregB]

I seem to remember a post from AL Eden.

His comment was the he mowed commercially with the twins.

He said like above, check oil and keep it full.He had no problems with mowing slopes and engine life as I recall.

 

[Snojetter]

Good to know proper oil level is the key and no real issue with the sidehills.  I always had concern that I might be doing some damage, but I've had this property since 2006 and there's no way I can mow uphill and crest the lip of the ditch without hanging up...so sidehill it is.  I did blow up a K301 in my Allis 712 early on, but that I'm sure was due to a low oil level.  The two Magnum's I run currently haven't lost a drop of oil over the course of a season in all the years I've owned them.  I feel pretty good about the longevity of these engines!

Edited September 14, 2024 by Snojetter