Important Information About Small Engine Flywheels
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Three types of flywheels were used on the 10hp-16hp K-series Kohler engines. They are as follows:
- Very few of the early 10hp and 12hp engines came with a 9-1/2" diameter flywheel with an unmachined edge, but no ring gear for the starter motor, and there's no way to install a ring gear. These engines used a Magneto ignition system. There's two magnets attached to inside the flywheel, the ignition coil is fastened on a stator to the bearing plate and a rope was used on a large pulley that was attached to the flywheel to crank the engine. There is no battery and no charging system involved. These were popular engines for the U.S. Military because there were very few parts to give trouble. The ignition coil is no longer available from Kohler for these models.
- Many of the early 10hp and 12hp engines came with an 8" diameter flywheel. The engine had battery-powered ignition, and a starter/generator provided the cranking source to start the engine and then it produced the power source to recharge the battery and power any electrical accessories.
- In later years, the 10hp through 16hp engines came with a 9-1/2" diameter flywheel with a machined edge for a starter ring gear and a ring of magnets on the inside. The engine had battery-powered ignition, and a small, gear type starter motor cranks the engine to start it and an alternator charging system produced the power source to recharge the battery and power any electrical accessories.
The Correct and Safe Way to Remove a Small Engine Flywheel -
To remove the flywheel from
a Kohler (or virtually any) small engine, remember, the retaining nut or
bolt have right-hand threads. Remove the flywheel with a quality-made automotive
harmonic balancer/vibration damper puller tool
(Lisle Corporation makes a sturdy puller) that have fine
threads and with a quality-made 1/2" impact wrench (with a large capacity
[minimum 30 gallon] air compressor reservoir tank) to literally "pop" the
flywheel off the crankshaft taper. Avoid using an imported puller because
it might move sideways when under pressure and break off the stud or bend
the bolt. Use the protective cap that's supplied with the puller to prevent
from damaging the threads on the end of the crankshaft. Apply grease or motor
oil on the threads of the center threaded shaft to increase the pulling torque.
The puller tool requires either two 5/16" or two 3/8" diameter grade 8 coarse
thread bolts with a thick flat washer under each bolt head so the head won't
pull through the puller's slots. And use bolts that's long enough so the
threads can penetrate the entire length of the threaded holes in the flywheel
to prevent the threads from being pulled out. Use a tap to clean the threads
in the flywheel if necessary. And although some flywheels are stubborn to
remove, just remember, it'll eventually come off. It's not made on the
crankshaft!
Personally, I use a quality-made 1/2" impact wrench running off of 150 psi of pressure with a 60 gallon air compressor tank and a Lisle harmonic balancer puller with grade 8 bolts w/flat washers to remove Kohler flywheels. I ain't never had one that was so stubborn it took effort to remove. My set up pops them off every time with little effort!
On most aluminum block engines,
such as Briggs & Stratton, Tecumseh, etc., a flywheel knock-off tool
can be used to remove the flywheel. You can get a knock-off tool at virtually
any place that sells small engine parts, and they come in 4 different sizes:
1/2" hole for older B&S engines, 7/16-20 NF, 1/2-20 NF and 5/8-18 NF.
To use the knock-off tool, for an older B&S engine with the crankshaft that has a long unthreaded shaft that protrudes into the starter clutch, the tool is placed on the end of the shaft, and for all other engines with a threaded stud on the end of the crankshaft, the tool is threaded onto the stud. A prybar is wedged under the flywheel against the engine block to provide extra leverage (and to prevent breaking the rod journal on the crankshaft), then a medium- to large-size hammer is used to sharply strike the tool perpendicular to literally "pop" the flywheel free from the crankshaft taper. To prevent from damaging the threads in the tool and on the crankshaft stud, always thread the tool all the way on the stud, and then back it off 1/2 turn. And don't strike the knock-off tool at an angle, or the stud on the crankshaft could get bent or break off!
But on small flywheels with no threaded holes to pull the flywheel, a knock-off tool of the correct thread size with a pry bar wedged under the flywheel and a medium size hammer can be used to remove the flywheel. Be sure to strike the tool perpendicular, too! Or a large 3-jaw gear puller can be used instead.
The Incorrect and Dangerous
Way To Remove A Small Engine Flywheel -
Most Kohler crankshafts are made of somewhat brittle cast iron material. So NEVER hit or strike the end of the crankshaft with a big hammer to remove a flywheel! And DO NOT attempt to use a wrecking bar (crowbar) to "pry" the flywheel off the crankshaft! Also, never use a large [2 or 3 jaw] outside gear puller to remove a flywheel. Doing any of these could break or crack the crankshaft and/or possibly crack the flywheel or break it in half. AND DEFINITELY DO NOT USE A KNOCK-OFF TOOL WITH A BIG HAMMER ON A KOHLER CRANKSHAFT WITH THE 5/8" STUD TO REMOVE THE FLYWHEEL! Being the crank is made entirely of cast iron, the stub will likely to break off!
A true story: One of my customers brought his walk-behind lawn mower with
a 3.5hp Tecumseh engine to me just to have the flywheel removed. When I was
working on it on my work table, I noticed the flywheel was wobbly and then
I found the crankshaft was broken in two at the connecting rod journal. I
thought this was odd, so I called the customer and told him about it, and
he said his neighbor tried to "pop" the flywheel off with a 10 lb. sledge
hammer! 
About Crankshafts Breaking at High RPMS -
A cast or billet steel crankshaft should survive as high as 7,000 rpms for a long time if they've been precision-balanced to the connecting rod and piston assembly. Some cast cranks break, and steel crankshafts are prone to breaking, too. When they do break, it's usually due to: being in an engine that broke the connecting rod and the rotating assembly came to a "sudden stop", and the flywheel kept wanting to spin, but cracked the crank instead; an out of balance flywheel (steel flywheels should be precision-balanced, too); and/or an out of balance starter pulley on the PTO end (which should also be precision-balanced). An out of balanced flywheel or pulley will cause the crankshaft to flex a few thousands of an inch at high rpms. When they flex, this causes metal fatigue, which creates a microscopic crack next to the rod journal, and they eventually break. Kind of like bending a piece of wire back and forth by hand, until it eventually breaks. I heard that the Magnum crankshafts are tougher than the old K-series cranks when precision-balanced. And when a crankshaft breaks at high rpms, it can also break a cast cam or bend a billet steel cam, which could crack the engine block at the cam pin on the flywheel side.
Always Use a Heavy [Steel] Flywheel on a Pulling Tractor!
Most of the time a heavier-than-stock, custom-made, machined
steel flywheel will add more "grunt" or more torque to an engine when pulling.
In our experience, a light-weight flywheel will cause an engine to lose power
toward the end of a pull. Light-weight flywheels are actually made for high
speed racing applications, such as for drag racing or race cars. A lightweight
flywheel works great for circle track racing because they allow the engine
to accelerate quicker and regain the rpm after coming out of the turns. A
heavy flywheel will "bog" an engine down and make it sluggish upon acceleration.
Pulling tractors on the other hand need ground speed (momentum) to do well in a pull, with the use of a heavier-than-stock flywheel. Once a heavy flywheel is spinning, it's hard to stop it or slow it down. A heavy flywheel may somewhat cause a [stock] engine to rev up slower, but once it's revved up, and because of the greater momentum force or increase of weight in the rotating mass, it'll "hold" the rpm longer, allowing a tractor to pull the sled right out the gate.
Remember, there's only two things to be gained by using a heavy steel flywheel; 1: the safety of steel versus cast iron, and 2: the increase in rotating mass with use of a heavier-than-stock flywheel. This means that a heavy flywheel will help an engine to produce more torque at higher rpm, which is very important for a pulling engine. A heavy flywheel (heavier-than-stock) will, without a doubt, will add more lugging power to an engine. That's why they're used on the large farm tractors. By the way - the 9-1/2" diameter OEM cast iron flywheel with the starter ring gear and full fins for the single cylinder 10-16hp Kohler K-series engines weighs 23-24 lbs.
Here's the dimensions if you want to fabricate a 9-1/2" diameter steel flywheel for the 10-18hp single cylinder Kohler engine:
- Overall diameter is 9-1/2".
- Total thickness is 2.250" (2-1/4").
- Diameter of the machined edge where the ring gear fastens onto is 9.250" (9-1/4").
- Degree of taper is 3.575º (most common) or 7.15º.
- Distance of inner taper to backside edge of flywheel is .875" (7/8").
- Length of taper is 1.375" (1-3/8").
- Diameter of small end of taper is 1.0625" (1-1/16").
- Distance from small end of taper to the edge where the ring gear butts up against is 1.71875" (1-23/32").
- Width of keyway is .1875" (3/16").
- When installing the ring gear on the flywheel, I'm not sure what the interference fit should be, but the normal rule of thumb is .001" per inch of the i.d. of the ring gear. This means that the surface for the ring gear on the flywheel should be .015"-.020" bigger than the i.d. of the ring gear. But make it somewhat large to begin with, and if the ring gear has trouble fitting, it can be turned it down .005". This rule applies to all flywheels.
If the above dimensions are somewhat confusing, then perhaps it's best to acquire a Kohler flywheel and take the measurements off of it.
By the way - the flywheel for the 10, 12, 14, 16hp flatheads and the 18hp OHV single cylinder Kohler K-series and Magnum engines will interchange. They all have the same taper in the center, and most of them have two or four tapped holes for accessories, and for using an automotive harmonic balancer/vibration damper puller tool to remove the flywheel from the crankshaft.
The best way to determine if an engine has either a cast iron or steel flywheel (if they look the same) is to tap it with a small hammer or wrench. Cast iron will make a "clunk" sound, and steel will have a high pitch ring to it.
And adding a heavy pulley on
the PTO end of the crankshaft would help add torque to the engine at high
rpms. But if/when the engine bogs down upon launch at the starting line or
several feet from the starting line, it may be hard to get it to rev back
up due to the extra spinning weight. So you gain one thing, but may lose
another.
NEVER INSTALL A DIRTY FLYWHEEL
ON A DIRTY CRANKSHAFT!
NEVER INSTALL A DIRTY FLYWHEEL
ON A DIRTY CRANKSHAFT!
Before installing the flywheel on a crankshaft, always use a clean cloth (white in color, to see the dirt) to remove any dirt, oil or debris from the crankshaft taper and most importantly, inside the flywheel taper. Use cleaning solvent (paint thinner) or brake cleaner because these leave no oily residue when they dry. And use emery cloth to remove any light rust. Clean both tapers thoroughly. This is very important because there must be direct metal-to-metal contact between the two tapers for a secure bonding of the parts. Because the flywheel must keep up with the rapid acceleration (or driving force) of the piston via the crankshaft. Do not use anti-seize for easy removal of the flywheel later! And there's no need to apply Loctite or Permatex on the tapers to install a flywheel to keep it from slipping on the crankshaft. If either of these are used, an acetylene torch will be required to remove the flywheel. If the flywheel needs to be removed later, use a quality gear puller and an air impact wrench or some muscle. Any oil, dirt or debris trapped in the tapers, or even anti-seize, will, without a doubt, allow the flywheel to slip or rock back and forth on the crankshaft, in which will shear the key, wallow out both keyways and possibly crack or break the flywheel and/or crankshaft. Dirt/oil on the tapers is the main reason why most custom-made billet steel high performance crankshafts break. And if the flywheel use a Cub Cadet or billet aluminum clutch hub adapter, be sure to install the [1-3/8" o.d.] thick flat washer under the retaining nut or bolt and then torque the nut or bolt to the proper specs.
A cast
iron flywheel with a crack in it, even a small crack, should never
be used on any engine!
Oil, grease, dirt on
the crankshaft and/or flywheel tapers or even an overtorqued nut or bolt
could cause the center in a cast iron flywheel to crack in the keyway or
the threaded stud of the crankshaft to break off. Cast iron flywheels always
crack at the weakest point, which is at the keyway. If the crack was welded,
and when the flywheel is installed on the crankshaft, and the nut or bolt
is torqued, the taper would still split next to the weld. But steel flywheels
don't crack (or break).
A crack in a flywheel will make an engine vibrate severely, plus it'll be noisy. (It'll make a "clunk, clunk, etc." sound at idle.) The crack will get worse over time, causing the flywheel to split in half at high rpm. If this happens, the two halves could cause severe bodily injury or possibly death if they were to become airborne and strike an innocent bystander.
The only valuable part on a cast iron flywheel with a crack in the keyway would be the starter ring gear. It can be installed on a [good] cast flywheel or a steel flywheel. Cast iron flywheels that's in good condition works great up to 4,000 rpm. (The factory setting of maximum rpm for virtually all small gas engines, including all of Kohler engines is 3,600.) Above 4,000 rpm, a steel flywheel is highly recommended for safety.
Below are the results of a cast iron Kohler
flywheel when spun well above 4,000 rpm -
The photos below are the results of a 9-1/2" diameter cast iron Kohler flywheel when it was spun at wide open throttle in a garden pulling tractor. This was a very serious accident that could have been a life-threatening tragedy. Remember: a well-constructed and precision-balanced steel flywheel is cheap compared to hospital bills, rehabilitation or funeral costs and not to mention the seemingly never-ending lawsuits!
The guy (name withheld) had just recently bought the Pro Stock motor. He already had the clutch setup on the flathead kohler twin he was running. According to what a friend of his told me (that also has a Pro tractor) the guy called him and asked would it be ok just to start the motor so he could hear it run. He was told not to turn it over 3,000 rpms. There is no question the guy knew he needed a steel flywheel and safety shields on the tractor before pulling it. I am confident those measures would have been on it before he pulled it the first time. There "was" someone standing by the tractor - the guy that owns it. He was working the throttle standing right in-line with the cast iron flywheel. You can see what it did to the air filter. Apparently it hit the carburetor and filter on its way to hitting him. It wasn't his leg that got the brunt of the piece of flywheel!
He just got too eager to find out what he had purchased and made a bad decision. It's an injury that will be with him the rest of his life. The point of putting these pictures on this site is so other pullers would not make the same mistake. I'm confident he is embarrassed by his actions...but he didn't have to share those pictures, ya know. I admire him for sharing these photos, and he's still suffering from the accident. - Story by Ron Ethridge
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It's recommended that
all flywheels, despite the material it's made of, be dynamically spin-balanced
on a precision balancing machine. The same machine to balance a crankshaft
can be used to balance a flywheel, too. And never use an automotive tire
"bubble balancer" to balance a flywheel! They are NOT precision!
Shielding of the Flywheel is Important!
I remember years ago, I was reading a club's rules, and it stated that all tractors must have a steel flywheel, and it must be shielded 360° with minimum 1/4" thick steel. I asked one of the pullers of the club, "why shield a steel flywheel? It's not going to break." And he told me: "There's a possibility that the end of the crankshaft could break off."
Actually, it's not rare that this kind of thing happens. It's happened to various pullers. The end of a crankshaft, despite if it's steel or cast iron, can break off next to the flywheel. It's a slight possibility. But then again, it could happen. Like the old saying goes: "A bad apple will spoil the bunch." And remember Murphy's Law? Must be prepared for the unexpected. So need to shield them flywheels folks, before a catastrophe happens.
With the tapers clean, and when
the flywheel nut or bolt is tightened or torqued to specs, the "squeezing"
action of the flywheel taper actually "grips" it to the crankshaft, guaranteeing
positive metal to metal contact, with no slip whatsoever. Torque the 15/16"
nut at 65 ft. lb., and the 3/8" bolt at 40 ft. lb., but do not overtorque
it! (As with an air impact wrench.) And Kohler's flywheel [castle] nut is
self tightening. Therefore, a lock washer isn't necessary. But sometimes
the nut will wear and tend to loosen over time. When this happens, the flywheel
could loosen, and the keyway in both the flywheel and crankshaft will become
damaged beyond repair. Therefore, a new all metal self locking nut is required
for a professional repair. But use a split lock washer on the bolt. And use
a grade 8 bolt, nothing less.
The best type of flywheel key to use in virtually any small engine is soft aluminum (4041 hardness). The reason for this is if the connecting rod breaks resulting in instant crankshaft lockup, the soft key will prevent damage to the flywheel and crankshaft. The aluminum key will shear in two, allowing the flywheel to slip on the crankshaft, preventing damage to either the flywheel or crankshaft. A steel key will cause a cast iron flywheel to crack or break, or if a flywheel loosens on the crankshaft, it'll wallow out the keyways. But if an aluminum V-belt starter pulley with ignition timing degree marks is installed on the PTO end of the crankshaft, there's really no need to install a flywheel key. The only reason most small engines use a flywheel key is to time the ignition, and not to prevent the flywheel from slipping on the crankshaft.
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 All metal self locking flywheel retaining nuts for threaded
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each at 65 ft. lbs. IMPORTANT: Apply thin coat of oil on threads of crankshaft
before installing nut.
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 Flywheel retaining
bolts for threaded hole in end of crankshaft. Each are grade 8, 1-1/2" long.
Available for....
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Steel Flywheel Keys
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 Extra Thick Steel Washers for retaining flywheel and/or Cub
Cadet aluminum clutch adapter hub to flywheel. A must to prevent hub breakage!
Available in 3/8", 5/8" or 3/4" diameter center hole x 1-1/4" o.d. x
approximately 1/4" thick. $3.00 each, plus shipping & handling.
(The 3/8" washer is the same used for the solid motor mount
kit.) |
 Steel Adapter
Step-Washer for mounting Cub Cadet aluminum clutch hub with 5/8" center hole
to Kohler Magnum crankshaft with a 3/8" bolt. A must to center hub and prevent
hub breakage! $8.00 each, plus shipping & handling. |
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 Used OEM Aluminum Clutch Drive
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Pin for aluminum clutch hub. 3/4" long. Secures above hub to flywheel to
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Rectangular key for 10-14hp
older 8" diameter K-series flywheel. Dimensions: 3/16" x 1/4" x 1-3/8" long.
OEM Kohler part # X-366-1-S. $2.25 each, plus shipping & handling.
Square key for Magnum 8hp and
6¼-16hp K-series 9" diameter flywheel. Dimensions: 3/16" x 3/16" x 1-3/8"
long. OEM Kohler part # X-286-17-S. $1.50 each, plus shipping
& handling.
Woodruff key for 10-16hp Magnum
engines. 3/16" x 1". Kohler part # X-46-3-S. $1.50 each, plus shipping
& handling.
Removing the Majority of the Fins from the Flywheel for Added Power -
One sure way to increase the
power output of an engine is to reduce the amount of drag that the flywheel
fins cause. To do this, the majority (about 3/4) of the fins will need to
be removed from the flywheel. For pulling competition, the flywheel will
still provide plenty of air to cool the engine. This shouldn't be done on
an engine for general yard work only because the engine could run hotter
than normal, causing premature wear.
And without a doubt (and using common sense), an altered flywheel definitely should be dynamically spin-balanced using a precision crankshaft/flywheel balancing machine. The same machine for balancing rotating assemblies (crankshaft and connecting rod/piston assembly) can be used to balance flywheels also. And never use an automotive tire "bubble" balancer to balance a flywheel! Also, make sure the flywheel has all the internal magnets intact (for the charging system) or remove the magnets altogether.
A 14" chop saw, like the ones that most automotive muffler shops use, can be used to remove the majority of the fins from the flywheel. To cut the flywheel fins off in a chop saw...
- First of all, wear an air respirator (surgical face mask) to prevent breathing in the cast iron and cutting wheel dust particles.
- Position the flywheel in alignment with the cutting wheel, firmly hold the flywheel with one hand and carefully bring the cutting wheel down even with the center of the flywheel. Rotate the flywheel, keep doing this until all the fins are removed. Try to keep the fins in alignment, too.
- Chuck the flywheel in a large metal lathe to true up the fins so they'll be the same height.
- And DEFINITELY have the flywheel dynamically precision spin-balanced afterwards at an automotive racing machine speed shop. And do not spin the cast flywheel (on the engine) no faster than 4,000 rpm!
-
A 1-1/2" diameter x approximately
24" long steel rod machined with a precision-machined taper to match the
taper in the flywheel and a threaded bolt hole in the end to retain the flywheel
will need to be fabricated for chucking the flywheel in the metal lathe and
spin-balancing of the flywheel.
Or better yet, install a billet steel flywheel and an electric fan to cool the engine.
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precision dynamically balanced, please contact A-1 Miller's Performance
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Phone: 1-573-875-4033. Please
call Monday-Friday, 9am to 5pm, Central time. If no answer, please try again
later. (When speaking with Brian, please be patient because I stutter.)
Fax: 1-573-449-7347.
E-mail:
pullingtractor@aol.com. You can
also contact us through Yahoo! Messenger:
Precision Dynamic Balancing Service - To balance a rotating assembly, I need the crankshaft, piston/rings, pin, clips, connecting rod and bearing inserts. The flywheel is balanced separately.
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Cooling the Engine with an Electric Fan -
Using a steel flywheel with no cooling fins, will without a doubt, allow any engine to operate at a much higher temperature. If you're burning methanol fuel and full synthetic motor oil, they'll help keep the engine somewhat cool, but the engine will still run hot from lack of a cooling system. Excessive heat will cause an engine to lose power and eventually "wear out." Therefore, installing an electric fan to cool the engine, especially between pull-offs, wouldn't be a bad idea. Pulling tractors that have a smaller engine (8hp or 10hp) usually don't go very fast down the track will really benefit from an electric cooling fan. Acquire a quality fan that can handle a lot of vibration, and mount it securely!
One type of fan that works great
for cooling a pulling engine is the Attwood Turbo 3000. It measures 3" in
diameter x 5" in length, draws 2.6 amps, and has 145 cfm air flow. It can
be securely mounted on the clutch cover or between the grille and PTO end
of the engine and aimed toward the exhaust area of the engine, because that's
the hottest part of an engine. These are available on
eBay and other places.
Another fan that works great for cooling a pulling engine is
the Vantec 92mm Tornado computer and electronic equipment fan (part # TD9238H).
On a Cub Cadet, this fan can be securely mounted between the grille and PTO
end of the engine, and aimed toward the exhaust area. This fan measures 3-13/16"
x 3-13/16" x 1-1/2", weighs 6.6 oz., draws 1 amp of power, has 119 CFM air
flow, turns at 4,800 rpm and the motor is supported by double, precision,
high-speed sealed ball bearings. But the fan will need to be wired separately
from the ignition (and electric fuel pump) circuits. These fans are available
on
eBay and at computer parts supply stores.
Return to a previous page or paragraph.
Because they draw power from the battery, which could weaken the spark for the engine, use an electric only to cool the engine after a pull, while driving the tractor around, or between pull-offs. And if the cooling fins on the engine block are clean (free of debris), if the throttle shaft isn't worn in the carburetor, if the ignition timing is set at 20 degrees BTDC, and if there's plenty of air blowing over the engine, then it should operate at a cool temperature.
To swap a starter ring gear from one flywheel to another, first
of all, Kohler don't sell just the ring gear by itself. You have to acquire
a used flywheel with a good ring gear on it.
- With the flywheel facing upward, use a large hammer to remove the ring gear from the flywheel. Tap gently and evenly around the entire gear to avoid warping or weakening the [ring gear] metal.
- Position the other flywheel face down, and lay the ring gear on it with the beveled edge of the gear teeth facing upward.
- Use an acetylene torch to heat the ring gear and it'll eventually drop down on the flywheel. This will expand it so it'll install on the new flywheel with ease. Do not hammer the gear onto the flywheel! Once in place, allow it to air cool.
By the way - the same starter ring gear fits the 8hp, 10hp, 12hp, 14hp, 16hp and the OHV (Over Head Valve) 18hp single cylinder Kohler K-series and Magnum engines. Only the 8hp flywheel itself is different. It's taper is smaller.
Widening a Narrow Frame Cub Cadet for
Use of a Large Flywheel and Gear Starter -
The larger 9-1/2" diameter flywheel with a starter ring gear, larger K-series bearing plate and K-series flywheel housing can be installed on any 10-18hp Kohler engine for use with the gear starter, as long as there's an indention in the block just above the starter motor's mounting holes (when using the upper-mount type starter). (The small flywheel is 8" in diameter.) If the engine is being installed in a narrow frame Cub Cadet (models 70, 71, 72, 73, 100, 102, 104, 106, 122, 124 and 126), the frame rails must be widened to accept the larger flywheel, bearing plate and flywheel housing. No charging system is required or recommended for a pulling tractor because it'll rob horsepower and add unnecessary weight and extra wiring. Read below for information on how to convert a narrow frame Cub Cadet.
If you want to do away with the old, heavy, battery draining, power-robbing
starter/generator on a narrow frame Cub Cadet and install a lightweight gear
starter along with the larger 9-1/2" diameter geared flywheel on a Kohler
engine, you'll have to widen the frame rails. To do this, with the engine
removed, cut a slot halfway down into the frame where the front of the flywheel
shroud sits. For the rear cut, measure 17" back from the front of the frame
(to where the metal bends for the clutch cover), and then make the cut there.
Then using a large pipe wrench or equivalent, bend or spread the frame rails
outward 11" from the front of the frame. Use a (large) flywheel shroud as
a gauge to determine how wide the rails would need to be. This will eliminate
having to put the engine in and take it back out again. Spread the frame
5" forward (towards front of tractor) from where the slot was cut. Then weld
a gusset into each wedge (or cut) opening. Use 1/8" thickness mild steel
to widen the frame rails. A Magnum flywheel housing and bearing plate
would require a lot more work to the frame rails to install in a narrow frame
Cub Cadet.
Widening the frame rails as mentioned above and then properly welding in the gussets shouldn't weaken it. But make sure that the frame is in fact straight before welding in the gussets. Because sometimes it can bend during the process of widening the frame. To prevent the frame from bending overtime when doing ground-pounding wheelies, weld in the gussets on both the inside and outside of the frame. Put down a good bead of weld, too. If the frame is bent, only slightly, this will interfere with the operation and proper alignment of the clutch and driveshaft.
There's no need to widen the frame rails on a wide frame Cub Cadet (models 86, 108, 128, 800, 1000 and 1200), because the large flywheel and gear starter will clear the rails.
The parts needed to convert a 10-16hp Kohler K-series engine with a starter/generator to a gear starter are as follows:
- Large diameter (9-1/2") flywheel with a starter ring gear.
- Large diameter bearing plate that's designed for flywheel above and a K-series gear starter and charging stator.
- K-series flywheel shroud for flywheel, bearing plate and starter above (for either an upper-mount or lower mount gear starter).
- K-series gear starter. (Lower mount for 7-8hp engines, and lower mount on the 10-16hp engines if the gas tank is in the way - not for Cub Cadets. Upper mount only on 10-16hp engines for Cub Cadets.)
- Starter solenoid (if your particular tractor/equipment requires one).
- Charging system (stator and solid state voltage rectifier/regulator).
But if you prefer to use the starter/generator when pulling, remember this: the generator part requires less than 1hp of engine power to charge a fully drained battery. Therefore, if you were to install an OFF/ON toggle switch to turn off the field windings in the starter/generator, this will prevent it from charging the battery. Which will allow the engine to produce more power.
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| If you need any of the items listed below, please contact
A-1 Miller's Performance Enterprises | 1501 W. Old Plank Rd. | Columbia,
MO 65203-9136 USA | Phone:
1-573-875-4033. Please call Monday-Friday, 9am to 5pm, Central time. If no
answer, please try again later. (When speaking with Brian, please be patient
because I stutter.) Fax:
1-573-449-7347. E-mail:
pullingtractor@aol.com. You can
also contact us through Yahoo! Messenger:
|
||
9-1/2" diameter genuine OEM cast iron Kohler K-series flywheel
for 10hp-16hp K-series flathead and 18hp OHV engines. These flywheels
are for battery ignition only, not magneto ignition. They're in excellent
condition and unaltered. No crack in the keyway, no broken or missing fins
and no cracked or missing internal magnets for charging system (if used for
yard use). These flywheels are for stock tractors
only; not to be turned above 4,000 rpm!
|
|
|
 Small Flywheel Shroud for
Kohler K-series 10hp-16hp flathead engines with 8" diameter flywheel,
starter/generator and battery ignition (Cub Cadet engines). OEM Kohler part
# 235375. (Discontinued from Kohler.)
|
 Large Flywheel Shrouds for
Kohler K-series 10hp-16hp flathead engines with 9-1/2" diameter ring gear
flywheel, upper-mount gear starter and battery ignition. OEM Kohler part
# 47 027 46-S.
|
 Aluminum bearing
plates for Kohler K-series 10hp-16hp flathead engines with 9-1/2" diameter
ring gear flywheel, upper- or lower-mount gear starter and battery ignition.
Supplied without bearing and oil seal. OEM Kohler part # 45 156 02-S.
|
All the parts needed to convert your 10hp-16hp single cylinder
Kohler K-series flathead engine from the small flywheel with the
starter/generator to the large flywheel with the ring gear starter.
The flywheel is for stock tractors only; not to
be turned above 4,000 rpm! Includes the following parts: [When
the used parts are available.]
NOTE: These are the older K-series flathead engine parts, not Magnum. All used parts are in excellent condition. And if you have a narrow frame tractor, the frame rails MUST be spread or widened for these parts to fit. Because there's no other way to make them work. And this conversion kit is meant mainly for pulling tractors. |
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Linked pages to our parts & services:
A-1 Miller's Performance
Enterprises |
Engine Rebuild Parts, Engine Rebuilds, Build-ups, Exhaust Header Pipe Kits and Machine Shop Services |
Transmission, Transaxle Parts, Rebuilds & Machine Shop Services |
|
Ignition, Electrical and Crank Trigger Electronic Ignition Parts and Kits |
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