Kohler Durability Improvements.

[Fordiesel69 210]

So in thinking about the one lung K Series or Magnums, if maintained can outlast the equipment they are one.  However there a three major areas of wear that I beleive could be improved. 

 

1.  Cylinder wear:  They get oval even when maintained as they approach their overhaul interval.  Does anyone know if a replacment cylinder sleeve made of better metal would help with wear?  There are tons of metal formulas automakers use to combat wear.  I beleive kohler formulates one type of cast iron, and makes the entire block out of it.  An aftermarket sleeve may be made of a better material.

 

2.  Crankpin wear:  Regardless of frequent oil changes, slightly after the combustion takes place the crankpin gets a bit of wear that creates a knock.  You can tear a perfectly maintained engine down and find a super smooth rod and crankpin, yet it still rattles.  Brain Miller seems to think a bearing insert will wear the crankpin less as the bearing material is much softer than aluminum.  However this makes me beleive that the bearing may  wear and need to be replaced more frequently.

 

3.  Valve Guide Wear:  Automotive valve guides can operate with a full valve seal and last over 100k.  My thought is if the original kohler guides are left in place and reamed out with new automotive ones, they may last longer.

 

All these are just thoughts, I would never be able to put enough hours on my equipment to verfiy if any of these would be beneficial, or be worse than the originial design.  Opinions on these? 

[jdleach 525]

1. There is a firm in California that makes special cylinder sleeves for a wide variety of engines. I know you can give them the specifications for the sleeve you want, and they will produce it. Many of the antique tractor enthusiasts use them for sleeves that are no longer available. As for different metallurgical content, I do not know what they offer.

Just did a Google, and several firms come up: Melling Sleeves, LA Sleeve, and others.

2. Was informed recently by a friend of mine into antique Farmall tractors, that there is a mod. for one lung Kohlers that replaces the rod with an inserted bearing to improve wear, and curtail the tendency for throwing the rod when these engines are operated on inclines. He did the mod. on his Cadet some years back after twice throwing a rod while mowing his yard. Has had no more issues. The idea came from a garden tractor puller friend.

3. There are several mods. that can be done to the valve train to improve longevity. Inserted seats, inserted guides, etc.

Edited May 19, 2014 by jdleach

[rmaynard 14,893]

You know, there something about the sound of a Kohler cast iron engine that will just disappear if you do all those mods. I don't know if I'd like that. The K241 engine on my first B-100 has never had anything done to it other than oil changes. The guides may be a little worn, and the cylinder may be a little out of round, and it just might have a bit of wear on the crank pin. But when I turn the ignition at -10 degrees with a foot of snow around me, and she fires right up and plows my driveway, I listen to the sounds of that cast iron Kohler and am thankful for the most dependable, noisy engine ever built. 

[SALTYWRIGHT 859]

DO NOT FORGET AUTOS ARE WATER COOLED AND KOHLERS ARE AIR COOLED.

[Desko 552]

IMHO all engines have there problems

onan-valve seat, rods

kohler-out of round cylinder, valve guides

briggs-(I've ran the heck out of em no problem) unknown

tecumseh-lets not even go there

Wisconsin-again no problems

Chinese clones- every thing

but at the end of the day a running motor is better than no motor right?

[shorts 182]

If you're asking can the K series engines be improved the answer is yes but at what cost?  We need to remember that the available technology when these engines were designed, developed and manufactured was a lot different than it is now.  Sure you can resleeve the cylinder with a high alloy that  won't wear as fast but then you will want to upgrade the rings and coat the upgraded pistons with a space age coating to help minimize friction. then you go to the valves and use something like bronze guides, stelite seats and valves, maybe even sodium filled valve stems. then go to a special rod with insert bearings and weld the crankpin with some exotic alloy to hardface it and have it remachined and you have take a 1950's flathead engine into the new millennium with all of the "good" parts and you now have a 1950's flathead engine that costs 10 times its design cost and might last twice as long as the original design that only lived for 25 years.

 

Take a look at what kind of money the pullers are spending to stay "in class" with their "stock" 12 or 16 hp Kohler pulling engines and it can get out of control pretty quickly,

 

I cut my teeth back in the day working on liquid cooled flat head industrial engines when the standard was to bore them at rebuild time .010, .020, .030, .040 over and then punch them out .187 and press in a sleeve and start over with a standard bore. the valve guides were knurled and reamed or reamed over and inserts installed then the were pressed out and replaced with new. valve seats were recut until they were to big or low in the block and then they were cut out and replaced.  cranks were ground several times and then welded up and returned to standard size.  The water pumps, governor's, magneto's, carburators, starters and charging systems were also rebuilt and returned to service many times.

[Fordiesel69 210]

Sounds like that would have been a fun time, when stuff was actually decent. 

[shorts 182]

Their is/are still decent modern stuff out their to work on, It's just different and better in different ways, the modern air cooled engines are aluminum blocks with hi alloy cast in place liners that last 3 or 4 times linger than the old cast iron engines they use piston rings that don't need as much tension to seal properly but wear out faster, the combination slows down the oval/taper wear pattern but it doesn't totally eliminate it, the piston skirts have friction reducing coatings and the rods have insert bearings or modified alloy castings for better bearings the cranks are either high alloy and or hardened for better wear the overhead valvetrain adds a bunch of parts but it also increases combustion efficiency for cleaner burning more economical performance. Lets not forget the pressurized oil systems instead of splash oiling which is probably the biggest single improvement by reducing crank and bearing wear as well as allowing for the modern OHV heads and combustion chambers. and last but not least how about the modern gasket and sealant technology to keep oil in and dirt out.  Just try to visualize a world where synthetic gasket material, silicone sealant, never seize, Teflon tape and loctite  didn't exist.

 

Now  after talking about all of the modern improvements to engines lets go find a 1937 Bentley and you will find a high moly cast iron block with an overhead camshaft and valve train complete with a vertical driveshaft in the front cover for the cam all encased in polished cast aluminum oil pan cam/head cover, bell housing and intake manifold with twin carburators. the only things missing were the high tech gaskets, seals and electronic management systems

[wrightorchid 261]

And I am sure you could hardly hear the Bentley when it was running.  Most of the older cars sound like a sewing machine when running.

[shorts 182]

Yes it sounds just like a Singer sewing machine, it belongs to 1 of my dads buddy's the old car guy.

The cast aluminum covers due an amazing job of keeping the noise inside the engine, the other part of the noise battle is getting the valves adjusted properly, it doesn't take much to have 1 loose valve and the whole engine sounds like it's about to come apart.

Edited May 21, 2014 by shorts

[oldlineman 1,450]

I to have a 1979 c-101 with a k241 that now only plows snow. It is not the fancy-est nor comfortable tractor to operate but is the most fun and I for one would not trade the sound of that old Kohler for all the new engines today, she still does the job. I'm with rmaynard  on this one.

[shorts 182]

I also have to agree that their is something about the K series Kohler's that can't be duplicated or replaced, a lot of it is the sound and feel of the power of a fresh K series properly tuned and working against the governor at WOT. the new high tech stuff is good stuff but I would still prefer the old school for it's simplicity and ease of repair.

[Fordiesel69 210]

I also have to agree that their is something about the K series Kohler's that can't be duplicated or replaced, a lot of it is the sound and feel of the power of a fresh K series properly tuned and working against the governor at WOT. the new high tech stuff is good stuff but I would still prefer the old school for it's simplicity and ease of repair.

 

But.......how cool would it be to improve upon the very design and still have all that?  Sleeve, bearing insert, & automotive valve guides.   Would be interesting if it did not cost a mint.

[km3h 543]

I have several tractors with Kohler K series engines that are in the neighborhood of 35 years old and still running smoothly and not knocking or slapping, nor are they burning oil. What's to improve on?