Cub Cadet 300 User Manual
Professional Shop Manual
300 Series Snow Thrower
NOTE: These materials are for use by trained technicians who are experienced in the service and repair of outdoor power
equipment of the kind described in this publication, and are not intended for use by untrained or inexperienced individuals.
These materials are intended to provid e su pp lem ental information to assist the trained technician. Untrained or inexperienced individuals should seek the assistance of an experienced and tr ained professional. Read, understand, a nd follow all
instructions and use common sense when working on power equipment. This includes the contents of the product’s Operators Manual, supplied with the equipment. No liability can be accepted for any inaccuracies or omission in this publication,
although care has been taken to make it as complete a nd accura te as possib le at the time of publica tion. However, due to
the variety of outdoor power equipment and continuing product changes that occur over time, updates will be made to these
instructions from time to time. Therefore, it may be necessary to obtain the latest materials before servicing or repairing a
product. The company reserves the right to make changes at any time to this publication without prior notice and without
incurring an obligation to make such changes to previously published versions. Instructions, photographs and illustrations
used in this publication are for reference use only and may not depict actual model and component parts.
© Copyright 2009 MTD Products Inc. All Rights Reserved
MTD Products Inc - Product Training and Education Department
FORM NUMBER - 769-05547
11/2009
Table of Contents
Chapter 1: Introduction .........................................................................................1
About the text format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Fasteners. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Assembly instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Understanding model and serial numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The 300 series snow thrower. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Chapter 2: Maintenance ........................................................................................ 5
Engine maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Auger / impeller maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Auger drive system maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Traction drive system maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 3: Traction drive system .........................................................................9
Description of the traction drive system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Wheels and Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Tire Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Drive Belt Replacement: Single-speed System . . . . . . . . . . . . . . . . . . . . . . . . 10
Drive Belt Replacement: three speed drive system . . . . . . . . . . . . . . . . . . . . 11
Drive Engagement Cable Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Speed Control Cable Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Transmission Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Transmission Internals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Chapter 4: Auger System.................................................................................... 23
System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Auger belt removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Auger control cable replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Auger housing Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Auger Housing disassembly: Pulley removal . . . . . . . . . . . . . . . . . . . . . . . . . 29
Auger housing disassembly: Impeller shaft bearing replacement . . . . . . . . . . 30
Auger housing disassembly: flight removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Auger Housing disassembly: impeller brake replacement . . . . . . . . . . . . . . . 34
Auger housing disassembly: Impeller removal . . . . . . . . . . . . . . . . . . . . . . . . 36
Auger Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Chute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
I
II
INTRODUCTION
CHAPTER 1: INTRODUCTION
Professional Service Manual Intent: This manual is intended to provide service dealers with information that will
help them maintain and repair the MTD 2-Stage snow thrower.
Disclaimer: The information contained in this manual is correct at the time of writing. Both the product and the infor-
mation about the product are subject to change without notice.
About the text format
Certain flags and key words are used to indicate the nature of the text that accompanies them. They are as follows:
! CAUTION! CAUTION
! WARNING! WARNING
! DANGER! DANGER
NOTE: “NOTE” is used to point-out helpful information that may not fit as a step in a procedure.
1. Numbered steps
1a. Sub steps
the actions required to complete a step.
• Bullet points: Indicate sub-steps or points of interest, without implying order or relative importance.
will be lettered and nested within steps. Two or more sub steps may be combined to describe
CAUTION: Indicates a potentially hazardous situation that, if not avoided, ma y result in
minor or moderate injury. It may also be used to alert against unsafe practices.
WARNING: Indicate s a poten tia lly haza rd ous situat io n tha t, if not a voide d, could r esult
in death of serious injury.
DANGER: Indicates an imminently hazardous situation that, if not avoided, will result in
death or serious injury. This signal word is to be limited to the most extreme situations.
indicate specific things that should be done, and the orde r in whic h th ey sh ou ld be do ne.
Disclaimer: This manual is intended for use by trained, professional technicians.
• Common sense in operation and safety is assumed.
• In no event shall MTD be liable for poor text interpretation, or poor execution of the procedures described in
the text.
• If the person using this manual is uncomfortable with any procedures they encounter, they should seek the
help of a qualified technician.
1
INTRODUCTION
Safety
This Service Manual is meant to be used along with the Operator’s Manual. Read the Operator’s Manual and familiarize yourself with the safety and operational instructions for the equipment being worked on . K eep a co py of the
Operator’s Manual for quick reference. Operator’s manuals may be viewed for free at the brand support website. It
will be necessary to have the complete model and serial number for the equipment.
• Be prepared in case of emergency:
Keep a fire extinguisher nearby
Keep a first aid kit nearby
Keep emergency contact numbers handy
• Replace any missing or damaged safety labels on shop equipment.
• Replace any missing or damaged safety labels on equipment being serviced.
• Grooming and attire:
Do not wear loose fitting clothing that may become entangled in equipment.
Long hair should be secured to prevent entanglement in equipment.
Jewelry is best removed.
• Protective gear: includes, but is not limited to
Clear eye protection
Protective gloves
Armored footwear
Hearing protection
Chemically resistant gloves
Respirator
Appropriate tinted eye protection
while working around any machinery
where necessary
when working around any machinery
in noisy environments
when working with chemicals or solvents
when working with chemical or solvents
when cutting or welding
! CAUTION! CAUTION
! CAUTION! CAUTION
! WARNING! WARNING
! WARNING! WARNING
Fame resistant headgear, jacket, chaps
• Remember that some hazards have a cumulative effect. A single exposure may
cause little or no harm, but continual or repeated exposure may cause very serious
harm.
• Clean spills and fix obviously dangerous conditions as soon as they are noticed.
• Lift and support heavy objects safely and securely.
• Be aware of your surroundings and potential hazards that are inherent to all power
equipment. All the labels in the world cannot protect a technician from an instant of
carelessness.
• Exhaust fumes from running engines contain carbon monoxide (CO). Carbon monoxide is a colorless odorless gas that is fatal if inhaled in sufficient quantity. Only
run engines in well ventilated areas. If running engines indoors, use an exhaust
evacuation system with adequate make-up air ventilated into the shop.
2
when cutting or welding
! CAUTION! CAUTION
! CAUTION! CAUTION
! DANGER! DANGER
INTRODUCTION
Fasteners
• The fasteners used on the equipment described in this manual, and the engine that powers it are a combination of metric and fractional inch. For this reason , wrench sizes are frequently identified in the text, and measurements are given in U.S. and metric scales.
• If a fastener has a locking feature that has worn, replace the fastener or apply a small amount of releasable
thread locking compound such as Loctite® 242 (blue).
• Some fasteners like cotter pins are single-use items that are not to be reused. Other fasteners such as lock
washers, retaining rings, and internal cotter pins (hairpin clips) may be reused if they do not show signs of
wear or damage. This manual leaves that decision to the judgement of the technician.
Assembly instructions
• T orque spec ifications may be noted in the p art of the text that covers assembly. They may be summarized in
tables along with special instructions regarding locking or lubrication. Whichever method is more appropriate
will be used. In many cases, both will be used so that the manual is handy as a quick-reference guide as well
as a step-by-step procedure guide that does not require the user to hunt for information.
• Lubricant quantity and specification may be noted in the part of the text that covers maintenance, and again
in the section that covers assembly. They may also be summarized in tables along with special instructions.
Whichever method is more appropriate will be used. In many cases, the information will be found in several
places in the manual so that the manual is handy as a quick-reference guide as well as a step-by-step procedure guide that does not require the user to hunt for information.
• The level of assembly instructions provided will be determined by the complexity of reassembly, and by the
potential for damage or unsafe conditions to arise from mistakes made in assembly.
• Some instructions may refer to other parts of the manual for subsidiary procedures. This avoids repeating the
same procedure two or three times in the manual.
3
INTRODUCTION
The 300 series snow thrower
The 300 series snow thrower is designed for the residential
user with moderate snow removal requirements
See Figure 1.0.
Features:
• 2-stage design
• Light-weight: 120 lbs. (54 kg.) typical
• 22” clearing swath
• Self-propelled, with internal clutch transmission
• Some versions are single-speed
• Some versions have 3 ground speeds
Figure 1.0
Understanding model and serial numbers
The model number of a the snow thrower described in this manual is 31A-32AD762. This manual is likely to carr y
useful information for a range of similar Snow Throwers that may carry a variety of MTD and private brand names.
The break down of what the model number
means is as follows:
• 31_ _ _ _ _ _ _ _ _ indicates that it is a snow thrower
• _ _A_ _ _ _ _ _ _ _ indicates that is the first generation of its basic design
• _ _ _ - _ _ _ _ _ _ _ indicates the type of starter ( - = recoil only, S = 110 V, M = 110 V+ alternator)
• _ _ _ _32_ _ _ _ _ indicates the engine used
• _ _ _ _ _A_ _ _ _ _ indicates the handle style
• _ _ _ _ _ _D_ _ _ _ indicates the housing width (D= 22” (56 cm), E= 24” (61 cm)
• _ _ _ _ _ _ _ _ 762 indicates the customer (styling, labels, color)
The serial number is 1H126G10012. The serial number
• 1_ _ _ _ _ _ _ _ _ _ engineering level
• _H_ _ _ _ _ _ _ _ _ month of production (A = Jan., B = Feb., C= March, D = April, E = May...)
• _ _12_ _ _ _ _ _ _ day of the month
• _ _ _ _6_ _ _ _ _ _ _ last digit of the year
• _ _ _ _ _G_ _ _ _ _ plant it was built in (B= Willard, OH., G= Brownsville, TN., I= Canada)
• _ _ _ _ _ _1_ _ _ _ _ assembly line number
• _ _ _ _ _ _ _ _ 0012 Shift/sequence number
Additional technical and service information is be available to our company authorized service center personnel
through our corporate offices, regional p arts distributors, and regional field support personnel. Please contact the
designated support office in your area or our corporate offices directly should further service information is needed.
reads as follows:
MTD Products LLC www.mtdproducts.com
P.O. Box 368022
Cleveland, OH 44136
Telephone: (800) 800-7310
4
Maintenance
CHAPTER 2: MAINTENANCE
Proper maintenance and storage key factors in keeping outdoor power equipment dependable. Encourage your
customers to bring snow equipment in for service and storage preparation at the end of each winter. Attending to
their snow throwers maintenance in the early spring will bring-in some pre-season work and prevent the barrage of
anxious phone calls when there is 8” of snow in their driveway.
Allow the engine to cool, and drain the fuel and oil from it before starting any mainte-
! CAUTION! CAUTION
Engine maintenance
All maintenance related material for the engine is covered in our horizontal shaft engine manual # 769-04015.
Save engine storage preparation for last.
Auger / impeller maintenance
1. Inspect the augers for bending or damage.
nance or service procedures.
2. Inspect each shear pin;
2a. It is possible for a pin to be sheared, with one end stuck
in place. Check both ends. Wiggle the auger to confirm that the shear pin is intact.
2b. Make sure that the shear pins have not ben replaced
with standard clevis pins or nuts and bolts.
2c. Use only the correct OEM shear pins.
NOTE: Shear pins help
mission if the augers hit a solid object hidden in the snow.
NOTE: If a shear pin breaks, the unique design of the
augers on current MTD snow throwers allows the next
auger over to continue driving the one with the broken shear pin. It is possible for a customer to continue
clearing snow without noticing a damaged shear pin, but it will double the forces on the next shear pin.
NOTE: The auger gear box is sealed and filled with grease at the factory and should not require any maintenance or service.
3. Wiggle the auger shaft to check the shaft-end bearings in the auger housing. Replace the bearings if they are
worn.
4. Check the auger drive transmission for any obvious damage. It is sealed a sealed unit, serviced by replacement of the complete transmission and auger shaft assembly.
5. Inspect the impeller;
prevent damage to the auger trans-
Shear Pins
Figure 2.1
5a. Wiggle the impeller to confirm that the roll pins that transfer drive from the input shaft are intact.
5b. The impeller should wiggle slightly, confirming that there are no for eig n ob je cts jamm ed beh in d th e imp el-
ler.
NOTE: The typical customer complaint will be that the augers turn, but the snow just oozes out of the discharge chute.
5
MAINTENANCE
6. Spray penetrating oil on the joints between;
• The auger shaft and the bearings in the auger housing that support it
• the augers and the auger shaft
• the augers and the shear pins
• the impeller shaft and the impeller
7. Check and adjust the shave plate and the skid shoes;
7a. Replace the shave plate if it is worn. It is generally best
to install the new shave plate with new carriage bolts
and locking nuts.
7b. Replace the skid shoes if they are worn.
7c. Skid shoe adjustment- place a length of corrugated
cardboard under the shave plate, supporting the
shave plate evenly about 1/4” (0.5cm) above the
ground. Push the skid shoes down against the
ground, then tighten the nuts that secure them.
Skid shoe Mounting bolts
Figure 2.2
Auger drive system maintenance
Allow the engine to cool, and drain the fuel and oil from it before st artin g any main-
! CAUTION! CAUTION
1. Remove the belt cover.
1a. Remove the screw on the right side of the of the
belt cover using a 3/8” wrench.
1b. Squeeze the locking tabs inward and slip
the belt cover up and off of the snow thrower.
2. Tip the snow thrower up onto it’s auger housing.
3. Inspect the auger belt for signs of wear or damage.
4. Disconnect the auger brake spring with a piece of starter
rope (the spring can be reached from the top, with the belt
cover has removed).
5. Apply a film of with lithium grease under the auger brake
arm
6. Work the brake arm back and forth to allow the grease to
spread evenly under the arm.
tenance procedures.
Figure 2.3
7. Add a light film of oil to the brake spring.
8. Replace the auger brake return spring.
6
Traction drive system maintenance
NOTE: Be careful to keep oil and grease away from the belts and pulleys.
NOTE: Replace any worn or damaged parts discovered during inspection.
NOTE: If a part has failed prematurely, identify and correct the cause of the failure.
1. Loosen the wheel bolts using a 1/2” wrench.
2. If not previously removed, take the belt cover off;
Maintenance
2a. Remove the screw on the right side of the of the
belt cover using a 3/8” wrench.
2b. Squeeze the locking tabs inward and slip
the belt cover up and off of the snow thrower.
3. Tip the snow thrower up onto its auger housing.
4. Inspect the moving parts of the system:
4a. Check the belts for wear or damage.
4b. Check the cables for wear or damage.
4c. Operate the traction clutch control bale; the cable and
clutch should move smoothly.
4d. Check the traction belt tension pulley; it should rotate smoothly and keep adequate tension on the belt.
4e. Check the cross-shaft bearings; wiggle the shaf t s. Ther e sh ould not be more th an .080” ( 2mm) play in the
shafts.
When checking actuating or belt-tensioning mechanisms, do not place your fingers
! CAUTION! CAUTION
5. For 3-speed snow-throwers;
5a. Relieve tension from the traction drive belt by drawing-back the tension pulley.
in an area where they might be pinched by unexpected movement.
70T Bull gear
14T Pinion
Gear
Figure 2.4
Drive Belt
Tension Spring
5b. Operate the speed control lever; confirm that the variable-speed pulley moves and returns smoothly.
6. Apply grease to the two drive gears.
7. Apply a light coating of oil to the transmission tension spring.
8. Spray some penetrating oil into the area between any rotating shafts and the plain bushings that they ride in.
9. Lubricate the axles so that the wheels can be removed easily in the future:
9a. Remove the wheels.
9b. Apply a light coating of anti-seize grease to the axle.
9c. Replace the wheels.
9d. Install the wheel bolts and Bellevil le washers; the outer lip of the washer should taper inwar d to contact the
outer edge of the axle.
9e. Tip the snow thrower back to its normal operating position.
9f. Tighten the wheel bolts to a torque of 20 in-lbs. (2.25 Nm).
10. Check and adjust the tire pressure to 20psi.
NOTE: The transmission is filled with gear oil and sealed at the factory. It is not intended to be serviced, and
will require no maintenance.
7
MAINTENANCE
FINAL
1. Reinstall the belt cover.
2. Spray some penetra ting oil in to the po ints of the control cables where the cable core enters the cable housing.
3. Re-fill the crankcase with fresh 5W-30 engine oil, and add a small amount of fresh gasoline to the fuel tank.
4. Test-run the snow thrower, testing all operation and safety features.
5. Prepare the engine for storage;
• Drain or run all of the fuel out of the engine.
• Remove the spark plug and add a small amount of motor oil to the cylinder, then replace the spark plug.
• Turn the crankshaf t 3-4 revolutions using the st arter rope. Stop when there is tension on the rope, leaving both
valves in the closed position.
8
TRACTION DRIVE SYSTEM
CHAPTER 3: TRACTION DRIVE SYSTEM
Description of the traction drive system
• A belt transfers power from the engine crankshaft to the input pulley of the transmission.
• A spring-loaded idler pulley keeps the belt under constant tension.
• On the three-speed version, a cable op er a ted var i ab le speed pulley changes the drive ratio to the transmission:
the sheaves of the pulley close or spread to change its effe ctive circumference. The idle r pulley automatically compensates for the change in belt tension.
• The transmission is a sealed unit with an internal clutch. The clutch is actuated by a cable attached to the drive
control bale on the handle.
• The transmission drives a 14T pinion gear which turns a 70T bull gear.
• The bull gear turns the axle at a 5:1 ratio from the transmission input shaft speed.
Wheels and Tires
IMPORTANT: The proper inflation pressure is a maximum
20 psi. See Figure 3.1.
Air pressure gauge
Uneven air pressure between the two tires ma y result in:
• Uneven tire wear
• Irregular drive tracking
• Pulling from one side or the other
If you encounter a snow thrower with
! CAUTION! CAUTION
NOTE: While it is possible to replace the tires on the
wheels, they are generally serviced as an assembly.
plastic wheels, see Special Reminder
Service Advisory MTD-098.
Do not overinflate the tires.
! CAUTION! CAUTION
Tire Replacement
1. Loosen the bolts that hold the wheels to the axles using a 1/
2” wrench. See Figure 3.2.
2. Tip the snow thrower forward onto its auger housing.
Allow the engine to cool, then drain
! CAUTION! CAUTION
the fuel and oil from the engine before
starting any service procedure.
Figure 3.1
Wheel bolt
3. Remove the bolts and slip the wheels off of the axles.
NOTE: The wheels fit onto the axle with a double “D”.
4. On installation, lubricate the axle shaft with anti-seize.
5. Install the bolts and Belleville washers with the outer edge
of the washers tapered in to meet the axle.
Figure 3.2
9
TRACTION DRIVE SYSTEM
DRIVE BELT REPLACEMENT: SINGLE-SPEED SYSTEM
1. Remove the belt cover:
1a. Remove the screw on the right side of the belt cover
with a 5/16” wrench or screwdriver . See Figure 3.3.
1b. Squeeze the locking tabs on the belt cove r inward while
lifting.
1c. Work the cover from between the engine and
discharge chute
Screw
Allow the engine to cool, then drain
! CAUTION! CAUTION
2. Tip the snow thrower forward onto the auger housing.
3. Remove the spring retaining nut from the anchor bolt on the side of the engine frame with a 7/16” wrench.
See Figure 3.4.
4. Disconnect the extension spring that draws the transmission toward an anchor bolt on the engine frame from the
anchor bolt.
the fuel and oil from the engine before
starting any service procedure.
Nut
Anchor bolt
Lock tab
Figure 3.3
Figure 3.4
10
NOTE: Use a length of heavy cord looped around the hook
end of the spring. See Figure 3.5.
Starter rope
Extension
spring
Figure 3.5
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