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Copyright © 1996-Present. This website created, designed and maintained by Brian Miller
Where Science and Common Sense Come Together for Better Engine Performance
This page was updated 3/7/18 (Click Refresh to see changes or updates.) Optimized for 1024 x 768 screen resolution. To search for a word or phrase in any of my web sites, press CTRL and F to open the Find dialog box in your web browser. Although every effort has been taken to check the accuracy of information contained herein, I cannot assume responsibility for errors.
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. A special dynamic balancing machine or an electronic digital scale 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, precision balancing of the rotating assembly and flywheel and low vibration saves wear and tear on internal engine components and attached external equipment.
If bolts, screws or nuts on the engine or tractor frame loosen due to engine vibration, there's no need to apply Loctite on the threads of the fastener. Just install a split lock washer of the correct size that fits the fastener (under the head or nut) then torque the fastener to specs. The lock washer will guarantee the fastener will stay tight. Or a self-locking nut can be used instead.
Here's some important information to remember - (Updated 3/7/18)
First of all, Kohler (and all other engine manufacturers) [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 the K301, K321, K341 and K361 engines have the same stroke. The crankshaft in the K321 and K341 Kohler engine, and the K361 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 K301 engines, which use a lighter weight piston than the K321, K341 and K361 pistons. The K301 crankshaft and piston assembly are a balanced set. Kohler use the same identical piston in their K341 and K361 engines. Although the connecting rods in these engines are made of different material, they weigh the same. Therefore, the crankshafts are balanced the same. The wrist pin is narrower in the K341 and K361 piston, making them weigh pretty much the same as the K321 piston and wrist pin.
HOWEVER, certain factory-type pistons come with a heavy wall wrist pin (weighs more), and others come with a thin wall wrist pin (weighs less). I believe that all OEM Kohler pistons come with a thin wall wrist pin, and most (or all) imported pistons come with a thick wall wrist pin. I'm not sure if there's a difference in the weight of the pistons themselves, and if this is why the manufacturer included a heavy or lightweight wrist pin to compensate for the weight of the piston to maintain engine balance. Anyway, to reduce the chance of severe engine vibration, use the heavy wall wrist pin in an engine that's going to run up to 4,000 RPM, and use the thin wall wrist pin in an engine that operates at a higher RPM.
The same crankshaft can be used with the K321, K341 and K361 piston assembly. If both counterweights on your crankshaft aren't machined off flat, then it's a 14 or K341 crank. If they are machined off, then it's a K301 crankshaft. And a K301 crank shouldn't be used with a K321 or K341/K361 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 K321, K341 or K361 crank is used with a K301 piston, because of the heavier counterweights, the crankshaft could eventually break. Because there's one opposing force working against the other. ("For every action, there's an equal and opposite reaction." - Newton's third law of motion.)
In other words, the K301 crankshaft is balanced differently from the K321, K341 and K361 engine crankshafts. Although the stroke and rod journal are the same, the counterweights on the K301 crank are different. The K301 piston assembly weighs less than the K321 and K341/K361 piston assemblies. Therefore, the K321, K341 and K361 crankshafts require more metal on the counterweights to balance out equally. And K321, K341 and K361 crankshafts are all balanced the same, which means that they're interchangeable between the K321, K341 and K361 engines.
Because of it's shorter stroke, the K241 crankshaft is different from the K301, K321, K341 and K361 cranks. The K301 crankshaft's counterweights are machined flat for the lighter-weight K301 piston/rings assembly, while the K321, K341 and K361 crankshaft's counterweights are rounded for the heavier K321, K341 and K361 piston/rings assemblies. The same crankshaft is used in the K321, K341 and K361 engines because their piston/rings assemblies weigh the same.
There's two types of K301 Kohler crankshafts. One is the early type. Its counterweights are the same width, and they're rounded with holes drilled. (Certain K241 crankshafts are like this, too.) The later K301 cranks have one wide and one narrow counterweight and both of them are machined flat to lighten them.
The crankshaft to the right is the very early model K301 version, because the counterweights are the same width. This crankshaft was produced in 1966-early 1969, before the K321 (and the K341 and K361, which share the same crankshaft because the piston assemblies are balanced the same) came into production. The K321 went into production in late 1969. The counterweights on the crankshaft for the K321, K341 and K361 engines, one is narrow and the other is wide. When the K321, K341 and K361 engines were manufactured, Kohler stopped making this type of crank and used the K321, K341 and K361 crankshafts in the K301. They just machined part of the counterweights off and drilled a few holes to bring it into balance with the lighter weight K301 piston assembly. And I have experienced certain K301 engines vibrate severely for some unknown reason. I had to have the crankshaft dynamically and precision spin-balanced and then the engine ran smooth with a lot less vibration. This goes to show that the technology for single cylinder engine balancing during the 1960's isn't like it is today.
K-series VS Magnum Crankshafts -
A K-series K301 crankshaft cannot be used with a K321, K341 or K361 piston/rings assembly without adding a lot of weight to the counterweights because the K301 crankshaft is balanced too light. The opposite would need to be done if a K321, K341 and K361 crankshaft is used with a K301 piston/rings assembly, or the engine would vibrate more than normal. If a K-series K301 crankshaft is going to be used in a K321, K341 or K361 piston assembly, it would need to precision spin-balanced.
The Magnum crankshafts are interchangeable with the older K-series crankshafts.... but the K301/M12, K321/M14 and K341/M16 Magnum crankshafts are all basically balanced the same... for a K301 piston/rings assembly. Some Magnum engines use three counterbalance gears. Just like the K-series, the two balance gears on the side of the block are to reduce the side-thrust of the counterweights of the crankshaft. But the lower balance gear in the Magnum is used to balance the rotating assembly because the Magnum counterweights are too light for the K321/M14 or K341/M16 piston/rings assemblies. Go here to learn how to align the three balance gears: Kohler Three Gear Balance Gear System Service Bulletin 208.pdf. (require Adobe Acrobat Reader and use Google Chrome web browser for a faster download of web sites with large files.)
For the heavier M14 and M16 Mahle piston/rings assemblies, the bottom balance gear simulates additional weight on the counterweights of the crankshaft so the engine will run with less vibration. If the Magnum balance gears are left out with any model, the engine will vibrate terribly! But if the balance gears are purposely left out, such as for high RPM operation, the rotating assembly would need to be precision balanced to reduce dangerous vibration. The older K-series engines will not vibrate more than it did before without balance gears installed.
And if a Magnum crankshaft is replaced with a K-series crankshaft, the Magnum balance gears shouldn't be used with the K-series crankshaft. If they are used, the engine may vibrate a lot.
If a Magnum (M12, M14 or M16) crankshaft require three balance gears, it can be used without the balance gears in a K-series block if it is precision spin-balanced to reduce the vibration (with the connecting rod and piston/rings assembly) on a crankshaft balancing machine.
And I have no idea why Kohler changed the crankshaft balancing with the Magnum single cylinder engines to a three gear balancing system. It make no sense at all to me. I mean, the way the older K-series engines was balanced worked great. But anyway, it'll be best to leave out the balance gears and have the rotating assembly (crankshaft, piston/rod assembly) dynamically and precision spin-balanced. By having this done, the engine, with no doubt, should run much smoother and possibly last longer.
The early K-series crankshafts have a 3/16" wide slotted [flywheel] keyway and a 5/8" diameter threaded stud w/nut to retain the flywheel, and the later K-series and all Magnum crankshafts have a #5 Woodruff [flywheel] keyway and a 3/8" bolt to retain the flywheel.
The K241/M10 crankshafts have a shorter stroke (2.875") than the K301, K321, K341 and K361 cranks (3.25"). The K241/M10 crankshafts are in a class by themselves. Therefore, they can't be used in combination with a K301, K321, K341 and K361 connecting rod or piston assembly without extensive machine work and precision balancing. And the K301, K321, K341 and K361 cranks can't be used with a K241 connecting rod or piston assembly without extensive machine work and precision balancing.
Identifying the Differences in the K-series Crankshafts -
Kohler's Dynamic Counterbalance System -
Various Kohler engine models K241/M10, K301/M12, K321/M14, K341/M16 and K361 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 counterbalance gears rotate in opposite direction of the crankshaft. These gears reduce the rotating side thrust (vibrating affect) of the crankshaft. Most K241 and M10 engines came from Kohler without balance gears. Only four K241 engines came from Kohler with balance gears installed. These engines have the specification number: 46578, 46590, 46593 & 46718. And only four M10 engines came from Kohler with balance gears installed. These engines have the specification number: 461509, 461513, 461526 and 461534. All other specification numbers for the K241 and M10 engines have no balance gears. However, if your engine vibrates a lot, it should to be precision spin-balanced. But most K241 and M10 engines (without balance gears) run smooth from the factory.
Unless a heavier crankshaft is used (than the original one that came in the engine), in some K241 Kohler engines, it will vibrate more if the balance gears are left out. But the K301, K321, K341 and K361 engines won't vibrate much more without the balance gears. And the balance gears in the K241 engine are the same as the ones used in the K301/M12, K321/M14, K341/M16 and K361 engines. They have the same OEM Kohler part number.
For reasons unknown why Kohler did this, some K301 Kohler engines will vibrate more without balance gears, while others don't vibrate much more without the balance gears. The counterweights on the crankshafts that vibrate more and the ones that don't vibrate as much look almost the same, too. Only the K301 engines experience this. Most K321, K341 or K361 engines don't vibrate much more without balance gears. Anyway, if the balance gears have been removed from a K301 engine, and it vibrates more than before, then the Crankshaft Balance Plate Kit from Kirk Engines http://www.kirkengines.com/index.php#CrankshaftBalancePlateKit can be installed, or have the rotating parts (crankshaft and rod/piston assembly) precision spin-balanced at an automotive speed shop. (A place that balance race car engines.)
For most single cylinder Kohler engines, balance gears isn't necessary.
Leaving out the balance gears shouldn't have a noticeable effect on engine vibration, but sometimes they help to reduce engine vibration. So if you choose to reinstall or leave them in an engine that will never turn more than 4,000 RPM (this is the maximum RPM for pulling in stock classes or for general lawn and garden use), 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 - the balance gears alignment tool (timing gage) is no longer available from Kohler. If you find a good used one or a new one from a Kohler dealer's old stock, the Kohler part numbers are 25 455 06-S, 10355 or Y-357. It's much easier to use this plastic tool when aligning the balance gears in time with the crankshaft. See the animated image to the right for correct identification of this tool.
Once, just for curiosity, after I've rebuilt a K301 Kohler engine, I've ran the engine with the balance gears installed and correctly aligned with the crankshaft. Then I removed the balance gears just to see if the engine would vibrate more. (It wasn't a lot of work to remove the gears. I removed the oil pan, snap rings, washers and spacers, rotated the crankshaft to clear the balance gears, and lifted the gears right out.) Anyway, I found that without the balance gears, the engine vibrated EXACTLY the same as when the balance gears were installed! Wonder why Kohler installed them in the first place. ????
Counterbalance gears does no good to install them. Most Kohler engines don't come with them and they do very little to help reduce engine vibration. When left out, the engine will not vibrate more than usual. Besides, being balance gears are made of cast iron and operate out of balance on a single needle bearing, they've been known to break and destroy the crankshaft, cam and engine block. I've seen this happen a few times. Therefore, I highly recommend leaving them out.
By the way - I've seen balance gears in the K241, K301, K321, K341 and K361 engines, but not every one of these engines have balance gears. I've even seen some Kohler Magnum M16 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.
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.
The balance gears in a Kohler engine can be removed without removing the crankshaft. Use quality-made heavy duty snap ring pliers with 90° tips to remove the [heavy gauge] snap rings that retain the balance gears. Because these snap rings are actually thicker than ordinary ones which makes them harder to expand. A flat screwdriver may need to be wedged under each snap ring to help them off the stub shafts. (Been there, done that many times. And it's difficult each time.) Be sure to remove the spacers (if equipped) and shims from the shafts, too. The counterweights on the K301 crankshaft are machined off, allowing room to remove the balance gears. But on a K321, K341 and K361 engine, one of the counterweights on the crankshaft may be in the way. If it is, try driving the pins into the crankcase from outside the PTO end of the block. By the way - the shims from removal of the balance gears can be used as camshaft shims to set the cam-to-block clearance on the K241-K361 engines.
Don't (re)install the balance gears in an engine if it's going to turn above 4,000 RPM! (The factory maximum RPM for virtually all small gas engines, including all of Kohler engines is 3,600.) The high RPM or wide open throttle operation 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, the balance gear stub shafts can be removed with a hardened 7/16" steel rod and a big hammer to drive them out from the PTO end of the block. They will fall into the block. And don't worry about driving out the stub shafts with a hammer, the engine block will not crack. But using a hydraulic press to drive the pins out could cause the block to crack.
The best and easiest way to plug the stub shaft holes is to cut 3/8" NPT threads into the holes from outside the block, and then install a couple of 3/8" NPT Hex Socket (Allen) pipe plugs. A special tool is required to install 1/2" cup-shaped expansion plugs in the stub shaft holes. And be sure to use RTV silicone sealant with either plug to prevent an oil leak, too.
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.) 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.
FYI - A cast iron flywheel with a broken off fin (fan blade) will definitely run out of balance, and cause the entire engine to vibrate badly. At higher RPMs (up to 4,000 RPM), the severe vibration could also cause the sheet metal to crack at the mounting bolt holes, and in rare cases, possibly cause the crankshaft to break at the rod journal. To statically (not spinning or in motion; at rest) put the flywheel back in balance, if the entire fin is broken off, simply break off the fin directly opposite of the broken fin with a hammer. But if only part of the fin is chipped off, use an angled hand grinder or a reciprocating saw / saw saw to remove about the same amount of chipped off material from the opposite fin. Try to make the fins match each other to maintain proper balance. The flywheel should still be safe to use, and the remaining intact fins will provide plenty of fresh air to adequately cool the engine. But the best way to put the flywheel 100% back in balance is to have it dynamically precision spin-balanced with an automotive crankshaft/flywheel balancing machine.
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.
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. 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.
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 and precision electronic digital scale that breaks at 1/10th of an ounce (0.1 lb.) or 1 gram to static balance a crankshaft to the piston and connecting rod assembly will be needed. For an example of how much 1/10th of an ounce is, a dime (10¢) weighs exactly 1/10th of an ounce (2.8 grams). But with a single cylinder engine, the engine will still vibrate some due to the side thrust of the counterweights, which is unpreventable.
How to Static Balance a Single Cylinder Engine:
If a high-performance K301 piston assembly is going to be used in a Kohler engine, a K321, K341 or K361 crankshaft can be used instead for rebalancing. Less weight will need to be added to the counterweights because of the smaller and lighter weight K301 piston assembly.
By the way - Actually, it's best to have the rotating assembly precision and dynamically spin-balanced with a crankshaft balancing machine. Because just bolting on a weight to side of one of the counterweights without spinning the crankshaft to check the balance against it and the rod and piston assembly may add too much weight or not enough and the engine might still vibrate a lot. I've seen this happen several times.
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.)
The reason most [high dollar] billet steel crankshafts break at wide open throttle is because they were not dynamically and precision spin-balanced using a specialized crankshaft/flywheel balancing machine. This happens when the counterweights on the crankshaft weighs much more than the piston and connecting rod assembly. When out-of-balance, the crankshaft flexes a few thousandths of an inch at high RPMs, which weakens the metal and causes fatigue cracks, eventually resulting in breakage. When a crankshaft breaks, it can destroy the camshaft and possibly the engine block. So it's very important that an aftermarket billet steel (and cast iron) crankshaft be dynamically and precision spin-balanced when the engine is ran at very high RPMs. Most manufacturers of billet steel crankshafts do not dynamically and precision spin-balance them. They include counterweights on the crankshaft that's pre-weighed and matched to the weight of the piston and connecting rod assembly to be used with the crankshaft. The counterweights must weigh the same as the piston and connecting rod assembly, with the exception of the weight of the rod journal, which counter-weighs the counterweights. When rotating, the rod journal too, adds weight to the piston and connecting rod assembly. And the same balancing machine that's designed to balance automotive crankshafts and flywheels can be used to balance single cylinder Kohler (and other makes of small engines) crankshafts and flywheels. To balance a crankshaft with a specialized flywheel/crankshaft balancing machine, all that is needed is a bob-weight that clamps on the rod journal. The bob-weight simulates the weight of (and must weigh exactly the same as) the piston and connecting rod assembly that is going to be used with the crankshaft to be balanced. If the piston and connecting rod assembly and/or crankshaft is used with another piston and connecting rod assembly and/or crankshaft, the rotating assembly will be out-of-balance.
But then again, when excessively out of balance, a billet steel crankshaft will not always break. A billet connecting rod will break instead. This happens when the piston and rod assembly weighs much more than the counterweights on the crankshaft. What happens is, as the engine rotates at high RPMs or at wide open throttle, the weight of the piston and connecting rod is sent upward a lot more than the counterweights are sent downward , resulting in two unequal opposing forces, and this places severe strain on the connecting rod cap' bolts. Eventually, the upward force of the piston and rod will cause the bolts to stretch (the 4-bolt hex socket (Allen) head cap screws (bolts) in certain billet rods are more prone to stretching), which will cause the rod to knock, and the continuing stretching of the bolts will cause them to break, ultimately resulting in connecting rod breakage, which can destroy the entire engine block. So it'll be a good idea to definitely spend the extra time and money to have your rotating assembly dynamically and precision spin-balanced.
If the engine still vibrates at high RPM or at wide open throttle after doing the above È, 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 would like to purchase any of the parts or services listed below Ê, or virtually any product or service mentioned in this website, please contact A-1 Miller's Performance Enterprises | 1501 W. Old Plank Rd. | Columbia, MO (Missouri) 65203-9136 USA | Phone: 1-573-256-0313 (shop) | 1-573-881-7229 (cell). Please call Monday-Friday, except holidays, 9am to 5pm, Central time zone. If no answer, please try again later. (When speaking with Brian, please be patient because I stutter.) A-1 Miller's shop is open to the public from 9am to 5pm, including weekends, except holidays. Please call before coming so I'll be here waiting for your arrival. E-mail: email@example.com. Directions to our shop | 1501 West Old Plank Road, Columbia, MO - Google Maps or Map of 1501 West Old Plank Road, Columbia, MO by MapQuest. Please click here to place an order.|
Quality Inductive Wireless Handheld Small Engine Tachometer.
A tachometer helps in setting the correct RPMs of an engine to prevent from
over-revving and possible damage to the engine. For gas/spark ignite engines
only. Works with magneto and battery-powered ignition systems. High quality
and very accurate. This handheld analog tach works great for checking/setting
the RPM on various small engines in the shop, and/or for checking/setting
the RPM [tech] on stock governored competition pulling engines. Hold sensor
(antenna) close to spark plug wire for reading. Operates off a self-contained
replaceable 9 volt battery. Has built-in battery voltage check. Reads up
to 5,000 RPM on the low scale, and 15,000 RPM on the high scale.
|High Quality Inductive Small
Engine Tachometer/Hour Meter. A tachometer is required in setting the
correct RPMs (normally 3,200 or 3,600 maximum for small engines) of an engine
to prevent over-revving and possible damage to the engine or dangerous flywheel
explosion. Very accurate. Can be hand-held to temporarily set engine RPM
or permanently mounted to monitor engine RPM at all times. Large 3/8 inch
LCD display. Works with all spark ignition engines by selecting engine type
using S1 and S2 buttons. Works with magneto and battery-powered ignition
systems. If tachometer does not turn on automatically as soon as engine
starts, press and hold the two buttons at the same time. Instructions
included. Tachometer reads up to 99,999 RPM. Hour meter reads up to 9999:59
hours/minutes then resets to Zero. Programmable maintenance hour setting
with service icon, a reminder when to change oil or other service. Can be
manually reset to Zero hours. Programmable maintenance hour setting with
service icon, a reminder when to change oil or other service. Easy installation:
Single wire wraps around spark plug wire and secured with two supplied nylon
zip-ties. No wire terminal connections required. Tachometer can be
surface-mounted and secured with two screws. Has built-in battery rated up
to 4 years. Sealed unit; weather and water resistant. Dimensions: 2" wide
x 1-3/4" depth x 3/4" height.
|High Quality Digital
Tachometer/Proximity Sensor Kits. A tachometer is required in setting
the correct RPMs (normally 3,200 or 3,600 maximum for small engines) of an
engine to prevent from over-revving and possible damage to the engine or
dangerous flywheel explosion. Will work with single- or twin-cylinder small
engines or multi-cylinder automotive engines, gas or diesel. Works with magneto
(with a battery to power the proximity sensor and tachometer) and battery-powered
ignition systems. Very accurate. Can be used for lawn & garden equipment
or competition pulling engines. Designed to be permanently mounted to monitor
engine RPM at all times. This precision digital tachometer operates with
external power and on the same principle as my
crank- or flywheel-trigger
ignition systems with a proximity sensor to detect a target, which can
be a small ferrous steel screw or pin, or magnet in a rotating disc on the
crankshaft or on/in flywheel. Cannot be wired in conjunction with the Dynatek
Dyna S or PerTronix Ignitor ignition modules. It must be wired separately
or can be used with any of my crank trigger ignition systems that also use
a proximity sensor. A sturdy steel or aluminum bracket will need to be fabricated
by customer to mount the sensor in close proximity of the detector/trigger
target. Set air gap/clearance at .010"-.188". Tachometer works with 8-24
volts DC, proximity sensors works with 6-36 volts DC. Tachometer can be in-dash
or panel-mounted. Dimensions for mounting hole: 3" wide x 1-17/32" wide.
Tachometer measures 1" in depth. Tachometer works with 8-24 volts DC, proximity
sensors works with 6-36 volts DC. Dimensions of each proximity sensor below:
15/32" (12mm) diameter x 1-3/8" thread length. Some proximity sensors have
an LED (Light Emitting Diode) on the rear of unit. If the proximity sensor
is wired incorrectly, the LED will stay on and go off when activated. Displays
up to 9,999 RPM. Very accurate. Tachometer returns to zero  when power
(ignition) is turned off. Wiring Instructions: #1 wire on tachometer connects
to brown wire on (either) proximity sensor and ignition switch (12 volt power),
#2 wire on tachometer connects to blue wire on (either) proximity sensor
and engine/chassis ground (battery negative () post), and #5 wire on
tachometer connects to black wire on (either) proximity sensor. Wires #3
and #4 connects to nothing. Wiring can also be integrated with
crank trigger ignition
with a proximity sensor. Choice of
BLUE numeric display.
|Solid Motor Mounts for Cub Cadet "Quiet
Line" Tractors - Replace Deteriorated "ISO" Rubber Motor Mounts with a Set
of Machined Solid Steel Motor Mounts! An original, ingenious,
innovative concept invention by Brian Miller, because I was the one who
originally thought of, promoted and advertised the use of this product.
Please accept no copycat
products of this kind.
Solid Motor Mounts for Wheel Horse - Replace Deteriorated ISO-Mounts with a Set of Machined Solid Aluminum Motor Mounts! An innovative concept invented by Brian Miller, because nobody else advertise and offer this product for sale. Please accept no other advertised copycat products of this kind.
|Used 9-1/2" diameter genuine OEM cast iron flywheel for Kohler
K-series K241-K361 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 fan blades and no cracked or missing
internal magnets for charging system (if used for general lawn and garden
use). These flywheels are for stock tractors only;
not to be turned above 4,000 RPM!
|Crankshafts for Kohler K-series
and Magnum K241-K361 engines. These cast iron cranks are a genuine Kohler
part, they're used, but in good condition. 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. And if you're going to use a pulley, clutch, etc., on
the PTO end, then I need to know the dimensions of the PTO shaft on your
crankshaft so we can match it to one that we may have in stock. Measure the
diameter and length from the gear teeth. [When available.]
Balance (cast or steel) flywheel for Kohler K241-K361 engines. $60.00 each labor, plus return shipping & handling.
Balance cast iron (Kohler) crankshaft and matching connecting rod and piston assembly. $200.00 per rotating assembly, plus return shipping & handling. NOTE: I will need to take your parts to the only reputable and trusted automotive machine shop in central Missouri (Jefferson City) that does professional engine balancing. Or you can contact Precision Machine, Inc. (PMI) to have your rotating assembly precision spin-balanced. They are located at 1703 Christy Drive, Jefferson City, MO 65101. Phone: 573-635-7214. Return To Previous Paragraph or Section
Retaining Nuts for threaded stud on end of K-series and steel crankshafts.
IMPORTANT: Apply thin coat of motor oil on threads of crankshaft before
installing nut then torque each at 65 ft. lbs.
|Flywheel retaining bolt for
threaded hole in end of crankshaft. Each are grade 8, 1-1/2" thread length.
Torque at 40 ft. lb. Replaces Kohler part # 25 086 253-S.
Flywheel / Aluminum Hub Retaining Washers. A thick, wide washer is a must to secure flywheel and prevent clutch/driveshaft aluminum hub adapter breakage! Each made of steel and measures 1-1/4" o.d. x approximately 1/4" thick.
|Steel Adapter Step Washers for Centering OEM Cub Cadet or billet
aluminum clutch hubs on crankshaft. A must to prevent severe wobble and prevent
hub and driveshaft/clutch breakage! NOTE: As long as the rotating clutch
components are trued-up in a metal lathe to minimize vibration, and the wide,
thick washer is used inside the hub to secure the hub to the flywheel, and
the flywheel retaining nut or bolt properly torqued, the OEM cast aluminum
clutch hub have been proven to hold up to a wide open throttle pulling
|OEM Kohler Aluminum Clutch
Hub Adapters. Fits John Deere and all models of Cub Cadet garden tractors.
|New main crankshaft bearings
for Kohler K-series and Magnum engine models K141, K160/K161 and K181/M8.
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 Kohler K-series and Magnum engine models K241/M10, K301/M12, K321/M14, K341/M16 and K361. These are specifically designed to provide maximum performance through precise ball implement selection. At high RPM or at wide open throttle, 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 & handling.
NOTE: If you cleaned all the oil out of the crankshaft main [ball] bearings and allowed them to dry, and when 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 then spin them. They should be a lot quieter. The same thing will happen with new ball bearings.
|If you would like to have your Kohler stock or pulling engine
tested on a
(dyno), please contact A-1 Miller's Performance Enterprises | 1501 W. Old
Plank Rd. | Columbia, MO (Missouri) 65203-9136 USA |
Phone: 1-573-256-0313 (shop)
| 1-573-881-7229 (cell). Please call Monday-Friday, except holidays, 9am
to 5pm, Central time zone. If no answer, please try again later. (When
speaking with Brian, please be patient because I stutter.) A-1 Miller's
shop is open to the public from 9am to 5pm, including weekends, except holidays.
Please call before coming so I'll be here waiting for your arrival.
Directions to our shop |
1501 West Old Plank Road, Columbia, MO - Google Maps or
Map of 1501 West Old Plank
Road, Columbia, MO by MapQuest.
A-1 Miller's Fully Computerized Stuska Water Brake Engine Dynamometer (Dyno) Service with DPM Data Logger Software!
For performance testing engines up to 200hp at speeds up to 12,000 RPM. The only engine dyno service in Missouri for Kohler pulling engines! Now set up and fully operational, customers can rent dyno time, fine tune and make adjustments or changes to their engines for maximum horsepower and torque, and print-out the results so their tractor(s) will be truly competitive on the track. NOTE: A fresh-built engine may not produce full power until it's broke-in. This is when the valves wear-in with the seats to completely seal in the compression. The rings will likely hold the compression, but the valves may leak slightly until they wear into the seats. This is normal for all engines and may take several hours or pulls to happen, then the valves will be able to hold full compression. Lots of pullers tell me after I've built their engines that it seems to pull stronger every time they pull it.
Engine Dyno Rental Fee: $30.00 per hour run time from the moment the engine is started. No setup fee for Cub Cadet engines with a 3- or 6-pin/stud clutch driver. An adapter may need to be needed or fabricated for other makes and models of engines. Only engines with the narrow base oil pan can be tested. Engines with the wide base (tall) oil pan cannot be tested at this time.
A-1 Miller's Performance Enterprises | 1501 W. Old Plank Rd. | Columbia, MO (Missouri) 65203-9136 USA | Phone: 1-573-256-0313 (shop) | 1-573-881-7229 (cell). Please call Monday-Friday , except holidays, 9am to 5pm, Central time zone. If no answer, please try again later. (When speaking with Brian, please be patient because I stutter.) A-1 Miller's shop is open to the public from 9am to 5pm, including weekends , except holidays. Please call before coming so I'll be here waiting for your arrival. E-mail: firstname.lastname@example.org. Directions to our shop | 1501 West Old Plank Road, Columbia, MO - Google Maps or Map of 1501 West Old Plank Road, Columbia, MO by MapQuest. You can also make the drive to A-1 Miller's shop to personally drop off and pick up your engine, transaxle, tractor, etc. for rebuilding or repairs. "The road to a friend's house (or shop) is never long."
To place an order, please call the number below Ê or send an email with your name, complete and correct postal address and phone number and so I can figure the total with shipping cost and USPS Tracking. For payment options for parts ordered or services performed, or to make a donation to my websites, I accept cash (in person), USPS Postal Money Orders, cashier's checks, business checks, MasterCard, VISA, Discover, American Express (please add 2.5% to the total for the credit/debit card processor's surcharge), Western Union Money Transfer, MoneyGram Money Transfers or Popmoney. (If a part for a specific purpose is special ordered, your debit/credit card may be charged for the full amount or as a deposit right after your order is placed; please do not send your debit/credit card information in email!) Or you can pay me through PayPal. (My PayPal account name is my email address. And be sure to mention in PayPal a description of what the payment is for.) If sending a money order, please include a note in the envelope with your name, complete and correct postal address, phone number and a description of what the payment is for. My mailing address and phone number are below Ê . I'll make a note of your order, and I may have to order some of the parts, which should take a few days to come in, but I will send the parts to you as soon as I have everything in stock after I receive your payment.
IMPORTANT - When sending your part(s) to me for rebuilding or repair, package everything securely so the item(s) won't get damaged in shipping and please include a note in the box with your name, mailing address, phone number (in case I have any questions) and a description of what you want done. When shipping heavy parts, it's best to put a slightly smaller box inside a larger box, to double the strength and integrity of the package. Because the clumsy "gorillas" or incompetent and uncaring workers that work for certain delivery services mishandle the heavy packages and don't care. And when the work is completed, I'll either call or email you an invoice with the total including shipping & handling.
To figure the shipping cost, I weigh the package with the parts, then I go online to the USPS Postage Rate Calculator website. I type in the weight, my zip code and your zip code, then it shows me the prices for various ways to ship the package. I always choose US Postal Service because I believe that's the most fastest, economical and reliable method.
Shipping: (United States and it's territories)
To save you shipping charges, item(s) in a package or cushioned envelope weighing less than 13 oz. is sent by First Class Mail for a 2-6 day delivery. Most packaged item(s) weighing over 13 oz. is sent by US Priority Mail for a 2-3 day delivery. To save you even more on shipping heavy items, I always try to use the US Postal Services' Flat Rate Priority Mail envelope and boxes (if the item(s) can fit inside the envelope or boxes). Some heavy items weighing no more than 70 lbs. is sent by US Mail Parcel Post. Item(s) weighing over 70 lbs. is sent by FedEx Ground. Again, if you're the kind of person who don't trust delivery/shipping companies (mis)handling your high-dollar and fragile merchandise, you can always make the long drive to A-1 Miller's shop to personally drop off and/or pick up your engine, transaxle, tractor, etc.
We Ship to Canada and Worldwide
Item(s) in a package or cushioned envelope weighing less than 1 lb. is sent by US Postal Service Airmail Letter Post for a 4-7 days delivery. Packaged item(s) weighing over 1 lb. and up to 66 lb. is sent by US Postal Service Airmail Parcel Post for a 4-10 days delivery. I cannot use the US Postal Services' Flat Rate Priority Mail envelopes and boxes to ship outside U.S. territories. Item(s) weighing over 67 lbs. or more is sent by FedEx Ground or equivalent services.
To make a payment to me through PayPal, go to PayPal's secure website ( https://www.paypal.com/ ) and click on Send and Request -> Pay for goods or services. Type in my email address, or copy and paste this: email@example.com, the amount and follow the directions. Be sure to mention in PayPal a description of what the payment is for. After you've finished, PayPal will send me an email notifying me that you have made a payment to me for the product(s) or services and amount entered. Then I go to their website and direct PayPal to deposit the money in my bank account. And I will send the parts to you as soon as I receive your payment. But I may have to order some of the parts if they're not in stock, which should take a few days. In that case, I will send you the parts as soon as they come in. PayPal protects your financial privacy and security. With PayPal, privacy is built in. It's a way for you to pay without exposing their financial information.
Coming Soon - Detailed Illustrated Plans on How to Construct a Professional Pull-Back Garden Tractor Pulling Sled, and a Motorized/Self-Propelled Garden Tractor Pulling Sled. FYI - My professionally-built motorized/self-propelled pulling sled, Track Master (click the picture to the right to see a larger image of my sled), is the only one I've ever built and I got it right the first time, with very few changes that had to be made to it. I guess I'm just one of those kind of guys that knows what he's doing. Pullers really like pulling my sled, too. They say it's the best sled they've ever pulled. (Not bragging, just stating the truth.) By the way - Track Master sled is engineered so well (by Brian Miller), other sled owners/builders have copied my well thought-out and proven design. Anyway, I have lots of work to do in my shop and I work on the sled plans in my spare time. As soon as my plans with an inventory list of parts to use are perfected, I'll post the update in my websites. Remember - Perfection takes time. If it's worth having, it's worth waiting for. Also, I plan to acquire a bigger shop and I may build high quality garden tractor pulling sleds in the future to offer for sale. Please call me at 573-256-0313 (shop) or 573-881-7229 (cell), or email me at firstname.lastname@example.org or email@example.com if you're interested. - Brian Miller
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