MTD Series 830 User manual

Shop Handbook
830-860 Series mowers
MTD Products Inc - Product Training and Education Department
FORM NUMBER - 769-03727
12/2007
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 provide supplemental information to assist the trained technician. Untrained or inexperi-
enced individuals should seek the assistance of an experienced and trained professional. Read, understand, and follow all
instructions and use common sense when working on power equipment. This includes the contents of the product’s Oper-
ators 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 and accurate as possible at the time of publication. 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 2006 MTD Products Inc. All Rights Reserved
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

Chapter 1: Introduction ......................................................................................................1
830 series ............................................................................................................................ 1
860 series ............................................................................................................................2
Chapter 2: Front wheels and axle ...................................................................................... 3
Front wheels ........................................................................................................................3
Front axle............................................................................................................................ 3
Chapter 3: Cutting blade .................................................................................................... 5
Chapter 4: Drive belt and baffles .......................................................................................7
Chapter 5: Speed control system ......................................................................................10
How the speed control works............................................................................................ 10
Speed control cable and lever.......................................................................................... 11
Clutch cable replacement ..................................................................................................14
Chapter 6: Transmission and rear wheels .......................................................................16
Transmission replacement ................................................................................................ 16
Low wheel mower ............................................................................................................ 16
Large-wheel mowers......................................................................................................... 21
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
1
The 830 and 860 Series lawn mowers are rear-wheel
drive self-propelled mowers with a unique variable
ground speed feature. They are both capable of mulch-
ing, bagging or side-discharging grass clippings. Both
mowers have a 21” (53cm) cutting swath.
NOTE: This manual was prepared using pre-
production mowers. The information contained
in the manual is true at the time of writing, but
the equipment may change without notice.
NOTE: This manual is intended to help profes-
sional technicians become acquainted with
newly introduced equipment, so that they can do
their jobs faster, better, and more easily.
If the user of this manual lacks tools or expertise
necessary to safely perform the tasks described,
they should seek the assistance of a trained pro-
fessional.
NOTE: As should be standard operating proce-
dure for any professional, test the operation of
the mower after any repair work, before return-
ing it to service.
CAUTION: Disconnect and ground the spark
plug wire whenever there is a risk of injury from
rotating parts. Working on the cutting blade or
drive system are two examples of situations that
could place a technician at risk.
CAUTION: Take measures to avoid the creation
of a fire hazard when working around equipment
that would normal contain fuel:
• Drain and store fuel in safe containers.
• Clean any fuel spills immediately.
• Avoid exposing fuel to heat sources or open
flame.
NOTE: Replace any worn or damaged fasten-
ers. If a lock washer or bellville washer has lost
its tension, replace it. If the locking feature of a
self-locking nut has worn, replace the nut, or
install it using releasable thread-locking com-
pound such as LoctiteTM 242 (blue).
830 series
The 830 series is identified by and eleven digit model
number, e.g.: 12A-83X-XXX.
“12” indicates that it is a self-propelled mower,
“A” identifies the first generation of the model series.
“A” may be followed by an engine identifier.
The “X”s will be style and retailer identifiers. Engines
from different manufacturers may be used on different
models. The models depicted here are in Troy-Bilt liv-
ery, but similar models may be produced in different
lines and for different retailers. See Figure 1.1.
Figure 1.1
CHAPTER 1: INTRODUCTION
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
2
860 series
The 860 series is very similar to the 830 Series except
for large rear wheels and some engineering differences
that are necessary to accommodate the large rear
wheels. See Figure 1.2.
Differences include:
• Lower handlebars are longer on the 860 Series
than they are on the 830 Series.
• The single-point height adjust lever is on the left-
hand side on the 830 Series, but it is on the
right-hand-side on the 860 Series.
• The handlebar brackets are different between
the two models.
• The 860 Series has different final-drive gears,
including an idler gear between the transmission
axle and the ring gear in the rear wheel.
Figure 1.2
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
3
Front wheels
The front wheels fit over the ends of the axle, and are
held to the axle by nuts. See Figure 2.1.
To remove the front wheels:
1. Loosen the wheel nuts using a 9/16” wrench.
2. Tilt the mower up so that the weight of the
mower is not resting on the front wheels.
3. Remove the nuts, and pull the front wheels off of
the mower. See Figure 2.2.
4. When reinstalling the front wheels, tighten the
nuts to a torque of 12 ft.-lb.(166.3 N-m).
Figure 2.1
nut
Figure 2.2
Wheel removed
Front axle
To remove the front axle:
1. Remove the front wheels.
2. Set the height adjuster lever to the highest posi-
tion, relieving the load on the lift-assist torsion
spring on the front axle . See Figure 2.3.
3. Remove the shoulder screw that holds the
height adjuster connecting link to the front axle.
Use a 3/8” wrench. See Figure 2.4.
CAUTION: The torsion spring on the front axle
will be under tension, even in the highest cutting
position.
Figure 2.3
Torsion spring
Figure 2.4
Shoulder screw
Height adjuster
connecting link
CHAPTER 2: FRONT WHEELS AND AXLE
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
4
4. Just inside of the deck shell, near each end of
the axle is a white plastic “C” clip. Remove both
“C” clips. See Figure 2.5.
5. The “C” clips hold flanged hex bushings into key-
hole slots in the deck shell. Slide the hex bush-
ings in to release them from the deck shell.
See Figure 2.6.
6. As the flanged hex bushings are released from
the deck shell, the axle will come free of the
shell. Maneuver the front axle to unhook the tor-
sion spring from the deck shell. See Figure 2.7.
7. The torsion spring is captive on the front axle. If
either is damaged, both must be replaced.
See Figure 2.8.
8. Reinstall the front axle by reversing the steps
used to remove it.
• Replace the “C” clips if they have lost their ten-
sion.
• Replace the flanged hex bushings if they are
worn.
• Do not trim the flanged hex bushings to ease
installation. They should be tight.
Figure 2.5
C clip
Front axle
Flanged hex bushing
Figure 2.6
Flanged hex bushing
Figure 2.7
Torsion
spring
Figure 2.8
Front axle weldment
Torsion spring
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
5
To remove the cutting blade:
1. Disconnect and ground the spark plug wire.
2. If the level of gasoline in the fuel tank is great
enough that it will spill if the mower is tipped,
remove the fuel filler cap, place a plastic bag
over the neck of the fuel tank, and reinstall the
cap.
3. Tip the mower with the muffler side down, or tilt
the mower back on a work bench, with the front
wheels up. See Figure 3.1.
4. Block the blade form rotating using a block of
wood or a blade holder tool.
5. Remove the blade bolt and diamond-shaped
bellville blade spring using a 5/8” wrench.
Figure 3.1
Blade
Bolt
Belville spring
6. Lift away the blade. See Figure 3.2.
7. Inspect the blade. If it is bent or worn beyond
proper sharpening, replace it with a new blade.
8. Sharpen and balance the blade if it is not badly
worn.
NOTE: The 830 and 860 Series mowers have a
3-in-1 blade. The outer part of the leading edge
cuts the grass. A wing behind it lifts the grass for
the next blade and propels clippings toward the
bag or side discharge chute if the path to either
is open. A stepped-upcutting edge just in-board
of the outer cutting edge mulches clippings as
they fall, if the side discharge chute is closed
and the mulch plug is in place.
Figure 3.2
Blade adaptor
CHAPTER 3: CUTTING BLADE
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
6
9. Check the blade adaptor for damage. There is a
wave washer on the crankshaft, directly above
the wave washer. See Figure 3.3.
10. Install the blade with wave washer, blade adap-
tor, and bellville spring washer properly posi-
tioned. Tighten the blade bolt to a torque of 38-
50 ft.-lb. (51-68 N-m).
Figure 3.3
Crankshaft
Wave washer
Blade adaptor
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
7
To remove the drive belt:
1. First remove the mulch plug. See Figure 4.1.
2. Remove the blade as described in Chapter 2:
Cutting blade..
3. Remove the baffle extension cover using a 3/8”
wrench. See Figure 4.2.
Figure 4.1
Mulch plug
Figure 4.2
Baffle
extension
4. Remove the rear baffle:
4a. Remove the two screws that hold the rear of
the baffle to the mower deck. The screws
are located just in front of the handlebar
brackets, and can be removed using a 3/
8” wrench. There is one on the left and
one on the right. See Figure 4.3.
4b. Remove the two nuts and bolts that hold the
right handlebarbracket to the mower deck
using a pair of 1/2” wrenches. They do
not hold the baffle in place, but they get in
the way of its removal. See Figure 4.4.
Figure 4.3
Baffle screw
Figure 4.4
Baffle (inset)
Bolts
Handlebar
bracket
Nuts on bolts that impede the
removal of the baffle
CHAPTER 4: DRIVE BELT AND BAFFLES
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
8
5. Remove the single screw that holds the front of
the baffle to the mower deck, using a 3/8”
wrench.
6. Pull the front edge of the baffle down, and
remove it from the mower. See Figure 4.5.
7. Crankshaft pulley cover removal:
7a. Remove the three screws that hold the
crankshaft pulley cover to the mower deck
using a 3/8” wrench.
7b. Pull the crankshaft pulley cover and the
lower sheave of the crankshaft pulley
down, freeing the belt from the crankshaft
pulley. See Figure 4.6.
8. Remove the belt by:
8a. Pull the belt down off of the crankshaft.
See Figure 4.7.
8b. Slip the belt out of the transmission pulley,
and remove it. See Figure 4.8.
Figure 4.5
Figure 4.6
Belt
Upper sheave
Lower sheave
Figure 4.7
Figure 4.8
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
9
9. Check the crankshaft pulley:
9a. The splines in both sheaves of the crank-
shaft pulley should be clean and smooth,
so that they slide together easily.
See Figure 4.9.
NOTE: The splines should not need lubrication.
If any lubrication is applied, use a dry PTFE
(TeflonTM) or graphite based lubricant in very
sparing quantities.
9b. The upper sheave of the crankshaft pulley
should slide off of the crankshaft. There is
a spacer above the sheave. The length of
the spacer will vary with the engine
model. If one end of the I.D. of the spacer
is rounded or beveled, that is the end that
goes up, toward the engine.
See Figure 4.10.
Figure 4.9
Upper sheave
of crankshaft
pulley
Splines
Figure 4.10
Crankshaft spacer
(varies with
engine model)
10. Replace the belt:
10a. Reverse the removal process.
10b. It will help to spread the sheaves on the
transmission pulley, and tug the belt deep
into the sheaves of the transmission pul-
ley. This will leave the maximum amount
of slack in the belt, so it is easier to slip
around the crankshaft pulley.
See Figure 4.11.
NOTE: Use only the Original Equipment belt.
Other belts of slightly different size or profile will
effect the grounds speed of the mower. Belts of
different material may wear-out faster.
Figure 4.11
Carefully spread the sheaves of the variable
speed pulley on the transmission to ease
belt installation.
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
10
How the speed control works
1. The red lever on the control panel applies ten-
sion to a cable. See Figure 5.1.
2. The cable runs down into the crankshaft pulley
cover, where it pulls on an arm that rotates a
cam. See Figure 5.2.
3. The cam has a series of ramps that work against
ramps in the crankshaft pulley cover, forcing the
two sheaves of the crankshaft pulley together.
4. When the crankshaft pulley sheaves squeeze
together, the force the contact patch of the drive
belt further out on the pulley. The outer part of
the pulley travels at a higher linear speed than
the part closer to the crankshaft, shifting the
drive ratio in the direction of greater speed.
5. Thebelt does not stretch any significant amount.
When the engine end pulley effectively grows,
the tension on the belt increases.
6. The sheaves on the transmission pulley are
spring-loaded to react to the added belt tension.
See Figure 5.3.
Figure 5.1
Red lever = speed control
Figure 5.2
Bottom end of
speed control
cable
Ramps
Figure 5.3
Power ratio to wheels Speed ratio to wheels
CHAPTER 5: SPEED CONTROL SYSTEM
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
11
7. The driven pulley (transmission) reaction is
opposite of the driving (engine) pulley. As a
given linear belt speed is applied to an effec-
tively smaller pulley, the drive ratio shifts in the
direction of increased speed. See Figure 5.4.
Figure 5.4
Engine pulley
Transmission
pulley
Power ratio to wheels Speed ratio to wheels
Speed control cable and lever
1. Remove the crankshaft pulley cover, as
described in the “DRIVE BELT” section of this
manual.
2. Un-hook the spring from the arm on the speed
control cam. See Figure 5.5.
3. Release the barbed fitting on the end of the
cable housing from the clutch housing. A 9mm
open-end wrench or a Ford fuel line tool can be
used to release the barbs. See Figure 5.6.
Figure 5.5
Crankshaft pulley cover
Speed control cam
Speed control
cable spring
Figure 5.6
Squeeze barbs
to release
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
12
4. Draw the cable and spring up through the open-
ing in the deck that the cables pass through.
See Figure 5.7.
5. Remove the three screws holding the cover to
the bottom of the control panel using a 1/4”
wrench or driver. Pull-down the cover to
remove it. See Figure 5.8.
6. Beneath the control panel on the handlebar,
remove the cable clamp screw that holds the
speed control cable in place. Use a 5/16”
wrench or driver. See Figure 5.9.
7. Pull the cable housing free of the control panel.
The stop at the end of the cable housing is usu-
ally placed in the notch that is second-nearest
the control lever assembly. See Figure 5.10.
NOTE: Moving the cable to a notch that is closer
to the control lever will shift the range of avail-
able ground speeds in a slower direction.
Moving the cable to a notch that is further from
the control lever will shift the range of available
ground speeds in the faster direction.
Figure 5.7
Pull cable
Figure 5.8
Cover
Screws
Figure 5.9
Clamp screw
Figure 5.10
Second
notch
Speed control
cable housing
Cable core
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
13
8. From this point, the cable-end can be maneu-
vered out of the control lever assembly, and the
cable can be removed completely.
See Figure 5.11.
9. Install the replacement cable by reversing the
removal process.
10. Speed Control lever:
10a. Disconnect the top end of the speed con-
trol cable, as described in the “Speed
Control Cable” section of this chapter.
10b. Remove the detent spring:
See Figure 5.12.
Figure 5.11
Detent spring
Figure 5.12
Detent spring
10c. Separate the control lever from the cable
quadrant by removing the screw that con-
nects them. Use a 5/16” wrench or driver.
See Figure 5.13.
10d. Pay attention to the orientation of the lever
to the control panel and the quadrant dur-
ing reassembly. See Figure 5.14.
10e. Reassemble the control panel by reversing
the order of disassembly.
NOTE: Some technicians find it easier too instal
the detente spring before installing the lever and
quadrant.
Figure 5.13
Cable quadrant
Figure 5.14
Speed control lever
Cable quadrant
Wide boss fits into
wide notch
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
14
Clutch cable replacement
1. Preparation:
1a. Remove the baffle as described in Chap-
ter 4: Drive belt and baffles.
See Figure 5.15.
1b. Disconnect either end of the speed control
cable as described in the “SPEED CON-
TROL CABLE AND LEVER” section of
this chapter, and pull it through the open-
ing in the deck.
NOTE: The spring on the end of the clutch cable
is large enough that it is extremely difficult to pull
through the opening in the deck with the speed
control cable in place.
2. A barbed fitting and a spring connect the bottom
end of the clutch cable to the transmission.
See Figure 5.16.
3. Squeeze the barbs on the cable housing to
release it from the bracket on the transmission.
A 9mm open-end wrench or a Ford fuel line
removal tool may be handy for this task.
See Figure 5.17.
4. Once the cable housing is released from the
bracket, the spring on the end of the cable core
can be un-hooked from the clutch arm on the
transmission. See Figure 5.18.
Figure 5.15
Baffle
Baffle extension
Blade
Removed
Figure 5.16
Barbed fitting
Figure 5.17
Bottom end of
clutch cable housing
Bracket
Figure 5.18
Spring
Clutch arm
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
15
5. Pull the cable and spring through the opening in
the deck. See Figure 5.19.
6. Remove the push-barb fasteners that hold the
control panel to the upper handlebar.
See Figure 5.20.
Figure 5.19
Pull clutch cable up
Figure 5.20
Push-barb
fastener Clutch bale
bracket
7. Pry the cable bracket loose from the upper han-
dlebar. See Figure 5.21.
8. With the cable slack, the Z-fitting at the top end
of the cable core can be un-hooked from the
clutch bale. See Figure 5.22.
NOTE: Depending on parts availability, the cable
may have to be replaced in tandem with the
engine stop cable.
9. Install the replacement cable by reversing the
removal process.
Figure 5.21
Cable
bracket
Figure 5.22
Engine stop cable
Clutch cable
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
16
Transmission replacement
NOTE: The internal parts of the transmission are
not serviceable.
• If the mower suffers a drive failure that cannot be
attributed to the belt, control cables, or variable
speed pulleys, replace the transmission.
• If the transmission is visibly damaged (broken),
replace the transmission.
Low wheel mower
1. Preparation:
1a. Remove the baffle as described in Chapter
4: Drive belt and baffles. See Figure 6.1.
1b. Set the cutting height to the highest position.
1c. Support the mower by the back of the deck,
in such a way that the rear wheels can be
removed. See Figure 6.2.
2. Rear wheel and dust cover removal:
2a. Remove the rear wheels using a 1/2”
wrench. See Figure 6.3.
Figure 6.1
Blade
Baffle extension
Baffle
Removed
Figure 6.2
Rear wheels
elevated
Figure 6.3
Spur gear
Steel drive
gear in wheel
CHAPTER 6: TRANSMISSION AND REAR WHEELS
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983

830-860 SERIES SELF-PROPELLED MOWERS
17
2b. Hold the rear drive axle to prevent it from
rotating, and remove the spur gears using
a T-20 Torx driver. See Figure 6.4.
NOTE: The spur gears are side specific.
• The one that goes on the left side is stamped
with and “L”, and the one that goes on the right
side is stamped with an “R”.
• If they are mounted on the wrong sides, the
wheels will not drive.
NOTE: The screws holding the spur gears to the
drive axle are both conventional right-hand
thread.
Figure 6.4
Clamp drive
axle
2c. Slip the spur gears off of the drive axle ends.
See Figure 6.5.
NOTE: The Torx screw that holds the spur gear
to the drive axle should be installed with releas-
able thread locking compound such as LoctiteTM
242 (blue). Tighten it to a torque of 110-120 in.-
lb. (12.5-13.6 N-m)
2d. Pull the drive pins out of the cross-holes in
the drive axle. The pins should be lubri-
cated with a small amount of anti-seize
compound on reassembly.
See Figure 6.6.
2e. Remove the plastic dust cover that fits
between the wheel and the height
adjuster bracket.
Figure 6.5
“L”
Figure 6.6
Dust cover
Drive pin
Drive axle
Axle that supports
the wheel
www.mymowerparts.com
For Discount White Outdoor Parts Call 606-678-9623 or 606-561-4983