MTD 2005 800 Series User manual

Service Manual
2005 800 Series (839) Self Propelled Walk Behind Mower
MTD Products Inc - Product Training and Education Department
FORM NUMBER - 769-02089
10/2005
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 2005 MTD Products Inc. All Rights Reserved

1
Belt Removal ........................................................................................................................ 1
Blade Removal ..................................................................................................................... 2
Transmission/Control Cable Removal .................................................................................. 3
Front Axle ............................................................................................................................. 6
Rear Door ............................................................................................................................. 8
Trail Shield ........................................................................................................................... 9
TABLE OF CONTENTS

2

SERIES 830 SELF PROPELLED
1
This is a new series rear wheel drive self-propelled
mowers for 2005-2006 season. These models will be
offered with a Briggs & Stratton engine. The 839E
series comes with the electric start. There are many dif-
ferent adapter plugs to connect to battery pack to the
engines. Units with a Briggs & Stratton engine will use
a 629-04011 stye adapter plug.
629-04011 Adapter
1. BELT REMOVAL
1.1. Disconnect and ground the spark plug wire.
1.2. Drain the fuel tank or place a piece of plastic
under the fuel cap to prevent gas from leaking.
1.3. Position the Mower with the front of the mower
elevated.This will prevent any oil displacement
issue in the engine or transmission. See Figure
1.3.
NOTE: This would be the recommended posi-
tion for most service procedures.
1.4. Remove screw that secures baffle to deck using
3/8 socket. See Figure 1.4.
Figure 1.3
Figure 1.4
Screw Securing baffle to the deck
SERIES 830 SELF PROPELLED

SERIES 830 SELF PROPELLED
2
1.5. Remove belt from engine pulley. See Figure 1.5.
1.6. Pushing belt toward the transmission, remove
belt from transmission pulley.
1.7. Pull belt forward though baffle. See Figure 1.7.
NOTE: Belt will fit over blade.
1.8. Install the belt by slipping it over the blade.
1.9. Push the belt though baffle toward transmission
1.10. Slip the belt over the transmission pulley.
NOTE: Pulling the belt forward slightly while slip-
ping the belt over rear belt keepers will help
keep the belt on the pulley.
1.11. Slip the belt over engine pulley. See Figure 1.11.
CAUTION: Check to make certain that the belt is
within the belt keepers.
1.12. Reinstall the screw securing baffle to the deck.
2. BLADE REMOVAL
2.1. Disconnect and ground the spark plug wire.
2.2. Drain the fuel tank or place a piece of plastic
under the fuel cap to prevent gas from leaking.
2.3. Position the mower with the front elevated.
2.4. Secure the blade from rotating.
NOTE: Correct order is as follows:
Starting from the engine and working out:
1) Upper engine pulley
2) Lower engine pulley
3) Engine spacer.
4) Spring washer.890 x 1.70 x.048 - check orientation
5) Flat washer.885 x 1.850 x.060
6) Blade adapter
7) 21” Blade
8) Blade bell support
9) Blade bolt 3/8-24 x 1.50
Figure 1.5
Belt
Figure 1.7
Baffle Belt
Figure 1.11
Belt
Transmission

SERIES 830 SELF PROPELLED
3
NOTE: Torque is 450-600 inch pounds
3. TRANSMISSION / CONTROL CABLE
REMOVAL
3.1. Disconnect and ground the spark plug wire.
3.2. Drain the fuel tank or place a piece of plastic
under the fuel cap to prevent gas from leaking.
3.3. Remove the small cover from the control hous-
ing using a phillips screwdriver.
3.4. Disconnect the drive cable from the drive control
handle. See Figure 3.4.
3.5. Remove the spring bracket cover.
3.6. Move the height adjuster to the highest position
reducing tension on the height adjuster spring.
Blade stack up
Blade bolt Blade bell support
Blade
Blade adapter
Flat washer
Spring washer
Spacer
Lower engine pulley
Upper engine pulley
Figure 3.4
Drive cable
Drive control handle
3.7. Using some recoil rope or a spring puller CARE-
FULLY disconnect the spring. See Figure 3.7.
3.8. Support the rear of the unit with a 4 x 4 or equiv-
alent.
3.9. Using a 9/16 socket remove the rear wheels.
See Figure 3.9.
Figure 3.7
Height adjuster
spring
Recoil rope
Figure 3.9
4 x 4 Block Rear wheel

SERIES 830 SELF PROPELLED
4
3.10. Remove the screw and spacer securing cross
bracket to the front and rear height adjusters.
See Figure 3.10.
NOTE: There are left side and right side gears.
• If they are replaced on the wrong side, the drive
to that side will not work.
• Left gears have an “L” stamped on the inside
edge.
• Right gears have a “R” stamped on the inside
edge.
3.11. Clamp a pair of vice grips on the axle near the
transmission case. See Figure 3.11.
3.12. Using a 10MM wrench remove the screw from
each side of the axle. This will allow the removal
of the washer, drive gear, dowel pin, and flat
washer. See Figure 3.12.
NOTE: The drive gears do have an “R” and “L”
on them for side indicators.
3.13. Remove the dust cover.
3.14. Using a 3/8 wrench remove one screw from
each side securing the baffle to the deck.
See Figure 3.14.
Figure 3.10
Screw and Spacer
Figure 3.11
Vice grips
Figure 3.12
Metric Screw
Washer
Drive gear
Dowel
Flat washer
Figure 3.14
Screw securing baffle

SERIES 830 SELF PROPELLED
5
3.15. Pull off both transmission bearing supports. See
Figure 3.15.
NOTE: Watch for the black spacer located
between the handle bracket and rear the bracket
assembly.
3.16. Remove the rubber grommet that surround the
control cable where it goes though the deck.
See Figure 3.16.
3.17. Elevate the front of the mower.
3.18. Remove the blade as described in the BLADE
REMOVAL section of this manual.
3.19. Remove the belt as described in the BELT
REMOVAL section of this manual.
Figure 3.15
Spacer
Bearing support
Figure 3.16
Rubber grommet
Control cable
3.20. Remove the baffle, transmission and rear deck
assembly all as one piece by tipping out the right
side first then lift left side over the bolt.
See Figure 3.20.
3.21. Pull the cable though deck.
3.22. Slide the rear assembly off the transmission
3.23. Remove the extension spring that connects
transmission to baffle See Figure 3.23.
NOTE: The extension spring can be replaced
without removing the baffle.
Figure 3.20
Baffle
Transmission
Rear deck Assembly
Figure 3.23
Extension spring

SERIES 830 SELF PROPELLED
6
3.24. Push out the transmission cable bracket.
See Figure 3.24.
3.25. Remove the cable from transmission bracket.
3.26. Remove the transmission from baffle. See Fig-
ure 3.26.
3.27. The cable can be disconnected from the trans-
mission by squeezing the tabs that secure the
cable housing to the bracket.
3.28. Inspect for damaged or worn parts. replace as
need.
NOTE: This producer is necessary to replace
the transmission or the drive cable.
3.29. Assemble mower by reversing the removal pro-
cedures.
NOTE: This is a non-serviceable transmission
the following is done as a professional courtesy
so you may see inside of the transmission.
4. FRONT AXLE
4.1. Remove the spring bracket cover
4.2. CAREFULLY using some recoil rope or a spring
puller disconnect spring. See Figure 4.2.
Figure 3.24
Cable bracket
Figure 3.26
Transmission
Figure 4.2
Spring
Recoil rope

SERIES 830 SELF PROPELLED
7
4.3. Remove the screw and spacer connecting the
cross bracket to front bracket assembly.
See Figure 4.3.
4.4. Lift and secure the mower so front end is off the
ground.
4.5. Pull both hairpins securing the split hex flange
bearings in place. See Figure 4.5.
Figure 4.3
Screw and spacer
Figure 4.5
Hairpin
4.6. Push both split hex flange bearing out of the
deck. Be certain to note orientation.
See Figure 4.6.
4.7. Pull the front bracket assembly out though the
slot.
4.8. Inspect and replace any worn or damage parts.
See Figure 4.8.
NOTE: Front axle is symmetrical from side to
side.
Figure 4.6
Split hex flange
Figure 4.8
Wave washer
Lock nut
Front wheel
Split flange
hex bearing

SERIES 830 SELF PROPELLED
8
5. REAR DOOR
5.1. The lower end of the handle needs to be discon-
nected and moved out of the way to access the
screw with a 3/8 socket. See Figure 5.1.
5.2. Once both of the screws are removed, carefully
move door toward front the of mower to relieve
tension on the springs.
5.3. Inspect parts for damage or wear. Replace as
need. See Figure 5.3.
5.4. When reinstalling spring in to rear door be sure
end is located properly. See Figure 5.4.
5.5. Make certain the spring is in the proper position
in the handle assembly.
See Figure 5.5.
Figure 5.1
Handle
1/4-20 Screw
Figure 5.3
Rear door
Door torsion springs
Door pivot rod
Figure 5.4
Locating hole
Figure 5.5
Locating tab

SERIES 830 SELF PROPELLED
9
6. TRAIL SHIELD
6.1. Remove both special screws from the handle
bracket assembly using a 3/8 wrench. See Fig-
ure 6.1.
6.2. Inspect the screws and trail shield for being
damage or worn. Replace as need.
See Figure 6.2.
Figure 6.1
Trail shield screws
Figure 6.2
Trail shield
Trail shield screws

SERIES 830 SELF PROPELLED
10