One of Brian Miller's Garden Tractor Pulling Tips & Tricks.

Balancing the Crankshaft to the Piston/Connecting Rod Assembly for a Single Cylinder Engine

This page was updated 4/27/09 (Click Refresh.)
To search for a word or phrase in this Web page, with Microsoft Internet Explorer, press CTRL+F to open the Find dialog box.

The basis of improved engine performance is precision workmanship. Every effort must be made to reduce friction and step up power. It must be remembered that extreme accuracy in setting the ignition timing, carburetion, together with a quality valve job, will give better than average performance. Contributing largely to stepped-up performance is precision balancing of the piston assembly and the connecting rod to the crankshaft counterweights. Special balancing equipment or an electronic digital scale (like the one pictured in this web site) is used for balancing the piston assembly/rod to the crankshaft so the total weight of the piston assembly/connecting rod is exactly the same as the crankshaft's counterweights. Also, superior balance and low vibration saves wear and tear on internal engine components and attached external equipment.

Here's some important information to remember -

Kohler [obviously] balance their engines at the factory. The crankshafts' counterweights are equally balanced to the weight of the piston assembly to reduce engine vibration. The crankshafts that's are used in the12hp, 14hp, 16hp [valves in block] and 18hp OHV (Over Head Valve) engines have the same stroke. The crankshaft in the 14hp and 16hp flathead cast iron block Kohler engine, and the 18hp OHV cast iron block Kohler engine are identical (except perhaps for the PTO end). Therefore, they're balanced the same and can be used in either engine. All these engines have the same stroke, too. Only the counterweights are different. More metal is removed (drilled and machined off) from the counterweights for the 12hp engines, which use a lighter weight piston. The 12hp crank and piston assembly are a balanced set. Kohler uses the same identical piston in their 16hp [valves in block] and 18hp OHV engines. Although their connecting rods are made of different material, they weigh the same. Therefore, the cranks are balanced the same. The wrist pin is narrower in the 16hp and 18hp piston, making them the same weight as the 14hp piston and pin. Therefore, the same crankshaft can be used with the 14hp, 16hp and 18hp OHV piston assembly. If both counterweights on your crankshaft aren't machined off flat, then it's a 14 or 16hp crank. If they are machined off, then it's a 12hp crankshaft. And a 12hp crank shouldn't be used with a 14 or 16hp piston assembly. The engine will vibrate more than usual and because of the heaver piston assembly, the connecting rod could stretch and eventually break. If a 14 or 16hp crank is used with a 12hp piston, because of the heavier counterweights, the crankshaft could eventually break. Because there's one opposing force working against the other.

In other words, the 12hp crankshaft is balanced differently from the 14, 16hp flatheads and the 18hp OHV engine crankshafts. Although the stroke and rod journal are the same, the counterweights on the 12hp crank are different. The 12hp piston assembly weighs less than the 14, 16 and 18hp piston assemblies. Therefore, the 14, 16 and 18hp crankshafts need more metal on the counterweights to balance out equally. And 14, 16 and 18hp crankshafts are all balanced the same, which means that they're interchangeable between the 14, 16 and 18hp engines.

The diffence between the 12hp crankshaft and the 14hp and 16hp crankshafts.

Actually, there's two kinds of 12hp Kohler crankshafts. One is with one wide and one narrow counterweight and both counterweights are machined off. The other, which is rare, the counterweights are the same width, and they're rounded with holes drilled. Some 10hp crankshafts are like this, too.

A 12hp crankshaft cannot be used with a 14hp, 16hp or 18hp OHV piston assembly without adding weight to the counterweights because the 12hp crankshaft is balanced too light. The opposite would need to be done if a 14hp, 16hp or 18hp OHV crankshaft is used in a 12hp block, or the engine would vibrate more than normal. The Magnum crankshafts are interchangeable with the older K-series crankshafts... as long as a 12hp piston assembly is used. But if the crankshaft is going to be used in a 14hp or 16hp piston assembly, it would need to dynamically balanced. Click here to read more about this. By the way - the only major differences between the older K-series and the newer Magnum crankshafts are where the flywheel fastens onto. The K-series have a 5/8" diameter threaded stud and the Magnums have a 3/8" threaded bolt hole.

The 10hp crankshaft have a shorter stroke (2.875") than the 12hp, 14hp and 16hp cranks (3.25"). The 10hp crankshaft is in a class by themselves. Therefore, they can't be used in combination with a 12hp, 14hp or 16hp connecting rod or piston assembly without extensive machine work and precision balancing. And the 12hp, 14hp and 16hp cranks can't be used with a 10hp connecting rod or piston assembly without extensive machine work and precision balancing.

Identifying the Differences in Kohler Crankshafts -

To identify the 10, 12, 14 and 16hp Kohler crankshafts, the 10hp cranks have a shorter stroke than the other cranks. You can compare a 10hp crank to a 12, 14 or 16hp crank by placing them side by side, and with the counterweights down, looking at the bottom part of the rod journal, the journal on the 10hp will be closer to the main journals. (3/8" of difference in stroke.)
The 12hp crankshaft is different from the 14 and 16hp cranks because the counterweights are machined off for the lighter-weight 12hp piston assembly. NOTE: Some 10hp cranks also have the counterweights machined off like the 12hp does, and some don't.
And the 14hp and 16hp cranks are identical in weight and appearance. Some may have a few more holes drilled into the counterweights, but that's the only difference.
Because of it's lighter weight piston assembly, the 12hp crankshaft is balanced differently or lighter from the 14hp and 16hp cranks. If installed in a 14hp or 16hp engine, the engine will vibrate more than usual and after a while, the connecting rod could break. If a 14hp or 16hp crank is used in a 12hp engine, the engine will vibrate more than usual and after a while, the crankshaft could break. So it's important that the right parts are correctly matched for durability of the engine, and not to mention operator comfort.

Kohler's Dynamic Balance System -

Kohler's Dynamic Balance System Some 10hp and larger single cylinder Kohler engines use a Dynamic Balance System, which are two out-of-balance gears that rotate on stub shafts that's pressed into the PTO side of the engine block. These balance gears rotate in opposite direction of the crankshaft. These gears reduce the rotating side thrust (vibrating affect) of the crankshaft.

Unless a heavier crankshaft is used (than the original one that came in the engine), in some 10hp Kohler engines, it will vibrate more if the balance gears are left out. But the 12, 14, 16hp flatheads and 18hp OHV engines won't vibrate that much more without the balance gears. And the 10hp engine requires different balance gears than the 12, 14, 16hp flatheads and 18hp OHV engines.

IMPORTANT! Don't (re)install the balance gears in an engine if it's going to turn above 4,000 rpm! (The factory maximum rpms for virtually all small gas engines, including all of Kohler engines is 3,600.) The high rpms could cause them to break and destroy the engine! So when building an engine that's going to turn above 4,000 rpm, these gears (and spacers) MUST be permanently removed! Remember - "An ounce of prevention is worth a pound of cure." It's okay to leave the stub shafts in the block. Or if you want, drive out the balance gear pins from the block (from the PTO end), cut 1/4" NPT threads and install a couple of 1/4" NPT Allen pipe plugs from outside the block. Be sure to use silicone sealer too, to prevent an oil leak. Or, the holes can be welded up solid.

And if a stock OEM-type piston assembly and connecting rod is going to be (re)used, there's no need to re-balance the crankshaft/piston/rod assembly if these gears are removed. If you want, leave the balance gears out. Actually, they're more trouble reinstalling and align with the crankshaft than they're worth. You won't notice that much difference in the vibration of the engine, either. It won't damage anything and it won't hurt anything. The engine will operate just fine without them.

By the way - I've seen balance gears in the 10hp, 12hp, 14hp and 16hp engines, but not every one of them have balance gears. I've even seen some 16hp Kohler Magnum engines have three balance gears! Anyway, it seems that Kohler was selective in which engines they put them in. Perhaps they only put them in engines that was installed in a "luxury-type" of garden tractor to help reduce operator discomfort. And every balance gear I've ever seen appear to be exactly the same weight and design.

For most single cylinder Kohler engines, balance gears isn't really necessary.

Leaving them out shouldn't have a noticeable effect on engine vibrations, but they do help to reduce engine vibrations somewhat. So if you choose to reinstall or leave them in an engine that will never turn more than 4,000 rpms (this is the maximum rpms for pulling in stock classes or doing ordinary yard work), make sure that the bearings in the [balance] gears and the stub shafts that they spin on are in good condition. If the bearings are worn and if the balance gears wobble, they'll wear the crankshaft gear teeth and they could break, possibly destroying the engine. By the way - you can get the balance gears alignment tool (timing gage) from your local Kohler engine dealer. The part number is 10355 or Y-357. It's much easier to use this tool when aligning the balance gears in time with the crankshaft. See the drawing to the right for correct identification of this tool.

Once, just for curiosity, after I've rebuilt a 12hp (K301) Kohler engine, I've ran the engine with the balance gears installed. Then I took them out to see if the engine would vibrate more. (It wasn't a lot of work to remove the gears. I just removed the oil pan, snap rings, washers and spacers, rotated the crankshaft a certain way, and then lifted the gears right out.) Anyway, I found that without the balance gears, the engine vibrated EXACTLY the same as when the gears were installed! Makes ya wonder why Kohler installs them in the first place. ????

The balance gears in a 12hp Kohler engine can be removed without removing the crankshaft. What's needed is a heavy duty snap ring pliers with 90º tips to remove the snap rings. Be sure to remove the spacers (if equipped) and shims from the shafts, too. The counterweights on the 12hp crankshaft are machined off, allowing room to remove the balance gears. But on a 14 and 16hp engine, the counterweights may be in the way. If it is, try driving the pins from the PTO end of the block instead and then plug the holes from the outside with a couple of 1/2" cup-shaped expansion plugs.

How To Remove the Crankshaft from a Kohler Engine -

Remove the piston/connecting rod, flywheel, bearing plate and anything that's on the PTO end of the crankshaft. (Not necessarily in this order.) And then, very gently, bump the PTO end with a wooden block to remove the crankshaft from the block. And there's no need to reinstall the balance gears. They serve very little purpose.

How Fast Can You Spin A Cast Iron Crankshaft?

As long as the piston assembly and connecting rod to the crankshaft counterweights, including the flywheel, starter pulley and clutch components are all precision balanced, you can spin it as fast as you want. Just make sure to have the crankshaft checked for stress cracks (magnafluxed) before using it.

If an engine vibrates severely, then the only things that causes the vibration is the piston/rings/wrist pin/clips assembly and/or the connecting rod isn't equally balanced to the crankshaft's counterweights. Another thing would be an out of balance flywheel. Also, if there's a parasitic accessory attached to the crankshaft, such as a bent pulley, it could be causing the vibration.

When installing a high-performance [heavier than OEM stock] piston and connecting rod assembly in a single cylinder engine, and to minimize dangerous vibration and to prevent the possibility of self destruction, the crankshaft must be re-balanced (more weight added to the counterweights) to compensate for the difference in weight.

Note: when using an OEM piston assembly and connecting rod, and if the rod journal (crank pin) on the crankshaft is reground for a smaller diameter bearing, that will not throw off the balance of the rotating assembly. Because the undersized rod bearing will take up the material that was removed from the crankshaft.

FYI - STATIC balancing is when parts are at rest, and DYNAMIC balancing is when parts are in motion. Dynamic balancing is a more precise way to balance anything that spins, but static balancing is a lower cost alternative... also proven very effective. An accurate electronic digital scale that breaks at 1/10th of an ounce (.001 lb.) or 1/2 of a gram to static balance a crankshaft to the piston and connecting rod assembly will be needed. For an idea of how much a gram weighs, a dime (10¢) weighs 2 grams.

How to Static Balance a Single Cylinder Engine:

Acquire a precision electronic digital scale that can weigh up to about 13 lbs., and one that will break at 1/10th of an ounce (.001 lb.) or 1/2 of a gram. A digital scale works much better for balancing an engine than a mechanical one. And the higher the capacity, the less precise it will be. The more precise it is, the better. Look on eBay for a quality digital scale.
Use pencil, paper and arithmetic for this procedure, to keep track of the results.
Weigh the stock (preferably std size) piston, rings, pin, clips and connecting rod as a unit. Make a note of the total weight. Be sure the scale is on a level surface. If it's not an inaccurate reading will result. Weigh the original piston/rod that came with the crankshaft. But if you don't have a piston/rod assembly available, here's the weights for them: The stock 12hp (K301) piston assembly and rod weighs exactly 29.1 ounces or 823 grams. And the stock 14hp (K321) and 16hp (K341) piston assembly and rod weighs in at 31.4 ounces or 891 grams.
Now weigh the high performance (or heavier) piston, rings, pin, clips, connecting rod and bearing insert as a unit. Write that weight down.
Subtract the two above weights and note the difference.
Now weigh the crankshaft that was originally used with the stock OEM piston/rod assembly. Record the weight on paper. The average weight of a typical cast iron Kohler 12hp (K-301) crankshaft is 151 oz., 9 lb. 7 oz. or 4,280 grams. And the average weight of a typical 14hp (K-321) and 16hp/18hp (K-341/361) crankshaft is 4,485 grams, 158.2 oz. or 9 lb. 14.2 oz. But the weight of every crankshaft will vary a few ounces depending on the length and diameter of the PTO shaft, if the PTO shaft has a drilled and threaded bolt hole, or if the flywheel end has a 3/8" threaded bolt hole or a 5/8" diameter stud. But remember, these numbers are for reference only.
Add the difference in weight to the crankshaft counterweights. Drill holes lengthways in the counterweights and weld in some heavy metal (tungsten steel), or fill in the factory drilled out holes with some lead capped with steel that's held in place with a roll pin driven in crossways, or weld or bolt some thin plate steel on the side(s) of the counterweights, etc. NOTE: Try to add an equal amount of weight to each counterweight so the crankshaft won't it be too heavy on either end. Not doing this may result in crankshaft breakage over time. And remember, crankshaft breakage could destroy other internal parts of an engine as well!
It must be a high-quality welding job whenever any welding is done on a cast iron crankshaft! Remember, cast iron is porous (it actually soaks up oil). This mean you must first heat the counterweights with an acetylene torch to burn the oil out of the metal. Then it'll be good for welding.
Weigh the crankshaft again and subtract the difference from the result that was derived in step 4.
The added weight to the crankshaft should now reflect the difference in weight of the two piston/rod assemblies. If it doesn't, it's OK to grind off some weight from the counterweights.
That's it! The crankshaft and piston/connecting rod assembly are now statically balanced.

If a high-performance 12hp (K301) piston assembly is going to be used in a Kohler engine, a 16hp or 18hp crankshaft can be used instead for rebalancing. Less weight will need to be added to the counterweights because of the smaller and lighter weight 12hp piston assembly.

Heavy metal (tungsten steel) and tools that's specifically made for crankshaft balancing can be purchased from GOODSON (http://www.goodson.com) Tools and Supplies for Engine Builders. (Request a catalog from them.)

IMPORTANT! An aftermarket steel crankshaft will need to be dynamically spin-balanced in a precision balancing machine if nothing has been balanced to it before. And the same balancing machine for automotive engines [and flywheels] can be used to balance single cylinder Kohler engines. All that is needed is a bob-weight that clamps to the crank journal. Also, the same balancing machine for automotive engines can be used to balance Kohler flywheels. Click here to see what can happen to an unaltered 9-1/2" diameter cast iron Kohler flywheel when spun well above 4,000 rpm.

If the engine still vibrates at high rpm after doing the above, it's either because of the side thrust of the crankshaft counterweights (which is normal in single cylinder engines), or if the vibration is severe, have the flywheel checked for precision balance and/or the clutch assembly trued up in a metal lathe. If you have a garden tractor with rubber motor mounts, these must replaced with solid metal mounts. If the crankshaft/piston/rod are balanced correctly and the flywheel is also balanced, and the tapers are clean, the crankshaft should last the life of the engine. Even when used in high-performance conditions.

If you need your crankshaft and piston/rod assembly and/or flywheel precision dynamically balanced, please contact me, Brian Miller, at A-1 Miller's Small Engine & Specialty Shop (1501 West Old Plank Rd., Columbia, Missouri. 65203 | Phone: 1-573-875-4033). Please call any day between 12 noon and 8:00 p.m. Central time, and please be patient because I stutter. | Fax: 1-573-449-7347. You can also contact me through Yahoo! Messenger: E-mail: pullingtractor@aol.com. We will soon be relocating our shop/business to a much larger facility at 1712 Business Loop 70 East, in Columbia, MO, offering many more quality parts & services to our customers! 1712 Business Loop 70 East, Columbia, MO - Google Maps

Balancing Service -

Balance flywheel (steel or cast) - $50.00 labor, plus return shipping.
Balance cast crankshaft - $125.00 labor, plus return shipping. To balance an engine, I will need the crankshaft, piston/rings, pin, clips, connecting rod and bearing inserts. The flywheel is balanced separately.
Balance steel crank - $150.00 and up (mallory extra), plus return shipping.

You can also have your flywheel and crankshaft/piston/rod assembly professionally dynamically precision balanced at:

Lakota Racing (http://www.lakotaracing.com/)
Midwest Super Cub (http://www.midwestsupercub.net/)
Vogel Manufacturing Co. (http://www.vogelmanufacturing.com/)

If you're looking for a steel crankshaft, aftermarket connecting rod or other engine parts, look in my advertisement web site or you can place a want ad in the same site.

Advertisement:

If you need a set of solid motor mounts, please contact me, Brian Miller, at A-1 Miller's Small Engine & Specialty Shop (1501 West Old Plank Rd., Columbia, Missouri. 65203 | Phone: 1-573-875-4033). Please call any day between 12 noon and 8:00 p.m. Central time, and please be patient because I stutter. | Fax: 1-573-449-7347. You can also contact me through Yahoo! Messenger: E-mail: pullingtractor@aol.com. We will soon be relocating our shop/business to a much larger facility at 1712 Business Loop 70 East, in Columbia, MO, offering many more quality parts & services to our customers! 1712 Business Loop 70 East, Columbia, MO - Google Maps By the way - these are not CNC machined. I fabricate these manually in my metal lathe.

Replace Deteriorated ISO-Mounts with a set of my Machined Solid Steel Motor Mounts -
Details include:

An alternative to the troublesome OEM rubber mounts. For Cub Cadet models 800, 1000, 1200, 1250, 1450 and 1650. Especially the models that are clutch driven.
Permanent replacement and a MUST for competitive pulling or everyday use because they stabilize the engine to prevent severe engine vibration at high rpms, and they save wear on the driveshaft components, especially the flexible 3-pin clutch drive plate.
For pulling competition, heavy towing, garden plowing, pushing snow, yard work or just lawn mowing.
Direct replacement - replaces the entire rubber mounts. They install between the tractor frame and engine mounting brackets. A flat washer fastens on top of the brackets.
Weighs just 4 ounces each.

$30.00 per set of four solid mounts (1 per corner), plus shipping.
$40.00 per set of four solid mounts with the mounting hardware. Each mount comes with a flat washer, grade 5 bolt, lockwasher and nut, plus shipping.

By the way - rubber motor mounts are intended for operator comfort from engine vibration only. The ISO mount tractors with solid motor mounts installed would feel and operate just like the older models with a solid mounted engine. And some people use my solid motor mounts just to mow grass and tell me that the mounts don't cause their tractor to vibrate much at all. But others have used them and said the vibration was unbearable. So I guess all I can say is try them. If you don't like them, return them for a full refund less shipping cost.
Can be easily removed if rubber mounts are used instead. If you'd prefer to use new rubber motor mounts, you can to visit your nearest NAPA auto parts store. They have a variety of rubber mounts. Some shock absorber mounts are the same thing.

Advertisement:

If you need any of the items below, please contact me, Brian Miller, at A-1 Miller's Small Engine & Specialty Shop (1501 West Old Plank Rd., Columbia, Missouri. 65203 | Phone: 1-573-875-4033). Please call any day between 12 noon and 8:00 p.m. Central time, and please be patient because I stutter. | Fax: 1-573-449-7347. You can also contact me through Yahoo! Messenger: E-mail: pullingtractor@aol.com. We will soon be relocating our shop/business to a much larger facility at 1712 Business Loop 70 East, in Columbia, MO, offering many more quality parts & services to our customers! 1712 Business Loop 70 East, Columbia, MO - Google Maps

10hp, 12hp, 14hp and 16hp K-series and Magnum flathead engine crankshafts. These cast iron cranks are a genuine Kohler part, in good condition, with good keyways. They may have either a 1" or 1-1/8" diameter x 3-1/2" long keyed PTO shaft and may have a STD or freshly reground .010", .020" or .030" undersized journal. Although .030" is rare, it's still safe to use. $85.00 each, shipping included. [When available.]

Flywheel retaining nut for older K-series crankshaft stud. 5/8-18 NF threads. Self-tightening jam nut. Torques at 65 ft. lbs. $1.00 each, plus shipping.
Flat washer for retaining flywheel and/or aluminum clutch hub adapter to flywheel. A must to secure flywheel and to prevent hub breakage! 41/64' i.d. x 1-1/4" o.d. x approximately 1/4" thick. $2.00 each, plus shipping. Machined Adaptor Stepwasher
Steel adapter step-washer for mounting the aluminum clutch hub with a 5/8" hole to the Kohler Magnum crankshaft with a 3/8" bolt. A must to prevent hub breakage! $8.00 each, plus shipping.
NOTE: I can also custom machine other adapter washers to fit your particular application. All I need is the dimensions. $10.00 each, plus shipping.

New main crankshaft bearings for 7hp and 8hp Kohler K-series and Magnum single cylinder cast iron flathead engines. These are specifically designed to provide maximum performance by means of precise ball implement selection. Heat treated. Made in China, but has the same quality as OEM Kohler bearings for long wear. Dimensions: 1.18" i.d. x 2.44" o.d. x .62" width. Part # 150-960. $10.00 each, plus shipping.
New 8 ball main crankshaft bearings for 10hp, 12hp, 14hp, 16hp (flatheads) and 18hp (OHV) Kohler K-series and Magnum single cylinder cast iron engines. These are specifically designed to provide maximum performance through precise ball implement selection. At higher rpms, bigger balls run cooler which create less rolling resistance than bearings with smaller balls. Heat treated. Made in China, but has the same quality as OEM Kohler bearings for long wear. Dimensions: 1.57" i.d. x 3.54" o.d. x .90" width. Part #150-973. $15.00 each, plus shipping.
NOTE: If you cleaned all the oil out of the crankshaft main [ball] bearings and then allowed them to dry, and then later you spun the bearings by hand, and if the bearings isn't worn much or at all, they might feel "rough" and make a rattling sound. This roughness or noise isn't necessarily because the bearing is worn out. The noise is mainly caused by the balls running dry on the races because there's no oil to separate them from the races. Try applying a small amount of motor oil to the balls/races and then spin them. They should be a lot quieter. The same thing will happen with new ball bearings.

For die-hard believers in balance gears!
Used 12hp, 14hp and 16hp balance gears with good, snug bearing. $10.00 per pair, plus shipping. (When available.)
Complete kit (balance gears, stub shafts, shims and snap rings) to convert an ordinary Kohler K-series and Magnum 10hp, 12hp, 14hp, 16hp (flatheads) and 18hp (OHV) single cylinder cast iron engines to Dynamic Balance. The two holes MUST be present in the block for this to work! $30.00, plus shipping. (When available.)

Linked pages to my parts & services:

A-1 Miller's Small Engine & Specialty Shop	Engine Rebuild Parts, Machine Shop Services, Engine Rebuilds & Build-up and Exhaust Header Pipe Kits
Carburetor, Fuel System Parts & Machine Shop Services	Clutch Parts, Rebuilding & Machine Shop Services
Transaxle Parts & Machine Shop Services	Steering, Chassis Parts & Machine Shop Services
Conventional Ignition, Electrical and Crank Trigger Electronic Ignition Parts and Kits	Brian Miller's Sled Rental and Sled Construction (Self-propelled weight transfer machine)

Please click HERE, e-mail me at pullingtractor@aol.com or call me at 1-573-875-4033 if you need various parts, machine work performed, repairs made, if your business would like to help sponsor my web sites or if you'd like to make a small donation toward my web sites. Please call between 12 noon and 8:00 p.m. Central time, and please be patient talking with me on the phone because I stutter. You can also contact me through Yahoo! Messenger:

Ã Return to Main Pulling Tips Page | Please Sign My Guestbook | Return To Previous Page | Classified Advertisements for Garden Pulling Tractors and Related Parts | Garden Pulling Tractor Engine Builders, Parts Suppliers and Service Providers | Brian Miller's Garden Pulling Tractor Picture Gallery | Pulling Sled for Garden Tractors Picture Gallery | Top of Page

Looking for a place to pull your tractor? Then check out this web site: Hot Links for Various Garden Tractor Pulling Clubs and Associations.

If you need any of the items below, please contact me, Brian Miller, at A-1 Miller's Small Engine & Specialty Shop (1501 West Old Plank Rd., Columbia, Missouri. 65203 \| Phone: 1-573-875-4033). Please call any day between 12 noon and 8:00 p.m. Central time, and please be patient because I stutter. \| Fax: 1-573-449-7347. You can also contact me through Yahoo! Messenger: E-mail: pullingtractor@aol.com. We will soon be relocating our shop/business to a much larger facility at 1712 Business Loop 70 East, in Columbia, MO, offering many more quality parts & services to our customers! 1712 Business Loop 70 East, Columbia, MO - Google Maps
10hp, 12hp, 14hp and 16hp K-series and Magnum flathead engine crankshafts. These cast iron cranks are a genuine Kohler part, in good condition, with good keyways. They may have either a 1" or 1-1/8" diameter x 3-1/2" long keyed PTO shaft and may have a STD or freshly reground .010", .020" or .030" undersized journal. Although .030" is rare, it's still safe to use. $85.00 each, shipping included. [When available.]
Flywheel retaining nut for older K-series crankshaft stud. 5/8-18 NF threads. Self-tightening jam nut. Torques at 65 ft. lbs. $1.00 each, plus shipping.	Flat washer for retaining flywheel and/or aluminum clutch hub adapter to flywheel. A must to secure flywheel and to prevent hub breakage! 41/64' i.d. x 1-1/4" o.d. x approximately 1/4" thick. $2.00 each, plus shipping.	Steel adapter step-washer for mounting the aluminum clutch hub with a 5/8" hole to the Kohler Magnum crankshaft with a 3/8" bolt. A must to prevent hub breakage! $8.00 each, plus shipping. NOTE: I can also custom machine other adapter washers to fit your particular application. All I need is the dimensions. $10.00* each, plus shipping.*
New main crankshaft bearings for 7hp and 8hp Kohler K-series and Magnum single cylinder cast iron flathead engines. These are specifically designed to provide maximum performance by means of precise ball implement selection. Heat treated. Made in China, but has the same quality as OEM Kohler bearings for long wear. Dimensions: 1.18" i.d. x 2.44" o.d. x .62" width. Part # 150-960. $10.00 each, plus shipping. New 8 ball main crankshaft bearings for 10hp, 12hp, 14hp, 16hp (flatheads) and 18hp (OHV) Kohler K-series and Magnum single cylinder cast iron engines. These are specifically designed to provide maximum performance through precise ball implement selection. At higher rpms, bigger balls run cooler which create less rolling resistance than bearings with smaller balls. Heat treated. Made in China, but has the same quality as OEM Kohler bearings for long wear. Dimensions: 1.57" i.d. x 3.54" o.d. x .90" width. Part #150-973. $15.00 each, plus shipping. NOTE: If you cleaned all the oil out of the crankshaft main [ball] bearings and then allowed them to dry, and then later you spun the bearings by hand, and if the bearings isn't worn much or at all, they might feel "rough" and make a rattling sound. This roughness or noise isn't necessarily because the bearing is worn out. The noise is mainly caused by the balls running dry on the races because there's no oil to separate them from the races. Try applying a small amount of motor oil to the balls/races and then spin them. They should be a lot quieter. The same thing will happen with new ball bearings.
For die-hard believers in balance gears! Used 12hp, 14hp and 16hp balance gears with good, snug bearing. $10.00 per pair, plus shipping. (When available.) Complete kit (balance gears, stub shafts, shims and snap rings) to convert an ordinary Kohler K-series and Magnum 10hp, 12hp, 14hp, 16hp (flatheads) and 18hp (OHV) single cylinder cast iron engines to Dynamic Balance. The two holes MUST be present in the block for this to work! $30.00, plus shipping. (When available.)