National Mower HYDRO 70" TRIPLEX User manual

HYDRO 70" TRIPLEX
NATIONAL MOWER CO. 700 Raymond Ave., P.O. Box 14299, St. Paul, Minnesota 55114-0299, U.S.A.
Phone [phone]  Fax [phone]
OWNER'S MANUAL
Includes Assembly, Maintenance &
Parts Lists
For Serial Numbers 1586 & Up
HYD70OM-8/99

HY70OM-8/99
2
DECLARATION OF CONFORMITY
according to Directive 89/392/EEC
We NATIONAL MOWER COMPANY
..............................................................................................................................................................
(Name of supplier)
700 Raymond Avenue, St. Paul, Minnesota 55114 U.S.A.
..............................................................................................................................................................
(Full address of the manufacturerauthorized representative in the community must also give the
business name and address of the manufacturer)
declare under our sole responsibility, that the product
NATIONAL HYDRO 70" TRIPLEX MOWER
(Make and model)
to which this declaration relates corresponds to the relevant basic safety and health requirements of the
Directive 89/392/EEC, (if applicable)
and to the requirements of other relevant Directives:
EN292-1&2--EN294--EN349
..............................................................................................................................................................
(Title and/or number and date of issue of the other Directives)
(If applicable)
For the relevant implementation of the safety and health requirements mentioned in the directives, the
following standard(s) and/or technical specification(s) has (have) been respected:
ANSI B71.4
..............................................................................................................................................................
(Title and/or number and date of issue of standard(s) and/or technical specification(s))
8/1/99
..............................................................................................................................................................
(Place and date of issue) (Name, function and signature of the authorized person)

NATIONAL HYDRO 70" TRIPLEX
®
3
National Mower Safe Operation Practices
For Riding Mowers
IMPORTANT
WARNING California, USA residents are required by law (CA PRC 4442 & CA H & SC 13005) to equip their
engines with spark arresters when operating in flammable vegitation. Arresters must be obtained from your
engine dealer and are not available from National Mower Company.
1. Know control functions and how to stop quickly. READ THE OWNERS MANUAL.
2. Do not allow children to operate the mower. Do not allow adults to operate the mower without proper
instruction.
3. Do not carry passengers. Keep children and pets at a safe distance from an operating mower.
4. Clear the work place of objects which might be picked up by the blades and thrown.
5. To start engine, operator must be seated, reel control must be disengaged and foot control must be in
neutral.
6. Take all possible precautions when leaving the mower unattended, such as shifting into neutral, stopping
the engine and removing the ignition key.
7. Do not stop or start suddenly when going uphill or downhill. Use extreme caution when mowing on slopes.
8. Reduce travel speed on slopes and in sharp turns to prevent tipping or loss of control. Use extreme caution
when changing direction on slopes.
9. Watch for holes in the terrain and other hidden hazards.
10. Watch for dangerous traffic when crossing or near roadways.
11. Never direct the discharge of material from operating reels toward bystanders nor allow anyone near the
mower during operation.
12. Handle gasoline with CAUTION - it is highly flammable.
a. Use an approved gasoline container.
b. Never fill the fuel tank indoors. Wipe spilled gas immediately.
c. Open garage doors to allow ventilation if engine is run inside-exhaust fumes are dangerous. Do not
run engine in any enclosed area.
13. Keep the mower in good operating condition. Make sure that all safety switches are operating properly
and all safety guards are in place at all times, except during servicing.
14. Keep all nuts, bolts and screws tight to be sure that the mower is in a safe working condition.
15. Never store the mower, with gasoline in the tank, inside a building where the fumes could reach an open
flame or spark. Allow the engine to cool before storing in any enclosure.
16. Keep the engine free of grass, leaves or excessive grease to reduce a fire hazard.
17. The mower and reels should be stopped and inspected for damage after striking a foreign object. The
damage should be repaired before restarting and operating the mower.
18. Do not change the engine governor settings or over speed the engine.
19. Proceed as follows when mowing.
a. Mow only in the daylight or in good artificial light.
b. Never make a cutting height adjustment while the engine (motor) is running.
c. Shut the engine (motor) off when removing grass or unclogging reels.

HY70OM-8/99
4
TABLE OF CONTENTS
Declaration Of Conformity ............................................................................. 2
Safe Operating Practices .............................................................................. 3
Introduction ................................................................................................... 5
Receipt of Shipment ...................................................................................... 5
Specifications ............................................................................................6-9
Engine Specifications ............................................................................ 6
Transmission .......................................................................................... 6
Vehicle Specifications ............................................................................ 6
Battery ................................................................................................... 6
Mower Specifications ............................................................................. 6
Weight and Dimensions ......................................................................... 6
Lubricants .............................................................................................. 6
Disposal Numbers .................................................................................. 7
Noise Emission and Vibration ................................................................. 7
Decals ................................................................................................. 7-8
Assembly Instructions .............................................................................. 9-10
General Information ......................................................................... 11-12
Engine .................................................................................................. 11
Traction Drive Train .............................................................................. 11
Reel Drive ............................................................................................ 11
Ignition Switch ...................................................................................... 11
Hour meter ........................................................................................... 11
Ammeter ............................................................................................... 11
Reel Control ......................................................................................... 11
Choke .................................................................................................. 12
Throttle Lever ....................................................................................... 12
Traction Pedal ...................................................................................... 12
Mow and Lift Treadle ............................................................................ 12
Free Wheeling Valve ............................................................................ 12
Drop/Lift Needle Valve .......................................................................... 12
Interlock Switches ................................................................................ 12
Operation .................................................................................................... 13
Adjustments ................................................................................................. 13
Traction Pedal ...................................................................................... 13
Reel Control Clutch ........................................................................ 13, 14
Seat Switch .......................................................................................... 14
Height of Cut ........................................................................................ 14
Reel to Bedknife ................................................................................... 15
Reel End Play ...................................................................................... 15
Backlapping Procedure .................................................................. 15, 16
Grinding Procedure .............................................................................. 16
Maintenance ............................................................................................... 17
General ................................................................................................ 17
Assembly and Disassembly .................................................................. 17
Battery ........................................................................................... 17, 18
Charging a Battery ............................................................................... 18
Bed Knife Replacement ........................................................................ 18
Fuel filter .............................................................................................. 18
Engine .................................................................................................. 18
Electrical System ................................................................................. 18
Hydraulic Hoses ................................................................................... 19
Hydraulic Oil......................................................................................... 19
Hydraulic Oil Filter ................................................................................ 20
Handle Bar Removal ............................................................................. 20
Jumper Cables ..................................................................................... 20

NATIONAL HYDRO 70" TRIPLEX
®
5
1INTRODUCTION
This manual has been prepared by National Mower
Company as an aid to users for assembly, maintenance,
adjustment and ordering replacement parts. Additional
information will gladly be furnished by calling or writing
National Mower Company.
Please furnish us with the Model Number, Serial
Number and Date of Purchase when contacting us about
your machine. Designations of right, left, front and rear are
used as if the operator was sitting in the mower seat.
NOTE
2RECEIPT OF SHIPMENT
Carefully inspect your machine and crate for damage
that could have occured during shipment. If damages or
shortages are noted, have the transportation companys
representative note this on the bill of lading.
Claims for shipping damages must be noted by the
consignee at the point of destination and filed with the
transportation company that delivers the shipment.
Lubrication ........................................................................................... 20
Painting ................................................................................................ 20
Belt Replacement ........................................................................... 20, 21
Coupling Alignment .............................................................................. 21
Storage ....................................................................................................... 22
General Instructions ............................................................................. 22
Engine .................................................................................................. 22
Battery ................................................................................................. 22
Tractor ................................................................................................. 22
Tires ..................................................................................................... 22
Starting After Storage ........................................................................... 22
Trouble Shooting Guide ............................................................................... 23
Engine Will Not Start ............................................................................ 23
Tractor Will Not Move ........................................................................... 23
Reel Not Turning ................................................................................... 23
Reel Will Not Cut .................................................................................. 23
Lubrication ..................................................................................... 24, 25
Electrical Schematic ............................................................................. 26
Parts List and Ordering Information ............................................................. 27
Tank and Rear Fork Assembly ....................................................... 28, 29
Steering Tower Assembly ............................................................... 30, 31
Engine and Footrest Assembly ....................................................... 32, 33
Traction Pedal and Pump Assembly ............................................... 34, 35
Lift Arm and Drive Assembly .......................................................... 36, 37
Front Cutting Unit Assembly ........................................................... 38, 39
Rear Cutting Unit Assembly ............................................................ 40, 41
Hydraulic Hose and Line Assembly ................................................ 42, 43
Hydraulic Fitting Assembly ............................................................. 44, 45
Basket Assembly .................................................................................. 46
Belt Too ............................................................................................... l46
Height Of Cut Bar ................................................................................. 47
Pump ................................................................................................... 47
Wheel Motor......................................................................................... 48
Lift Valve .............................................................................................. 48
Lift Cylinder .......................................................................................... 49
Front Roller Scraper Kit ........................................................................ 49
Rear Roller Scraper Kit ........................................................................ 50
Valve Block .......................................................................................... 50
Warranty ..................................................................................................... 51

HY70OM-8/99
6
3SPECIFICATIONS
3.1ENGINE SPECIFICATIONS
TYPE: Twin Cylinder, Air Cooled
ENGINE MODEL: Briggs & Stratton Vanguard
HORSEPOWER: 11.9 kw (16 hp)
COOLING: Ducted air flow
3.2TRANSMISSION
TRACTION DRIVE: Direct coupled variable displacement
hydraulic pump with high torque
wheel motors.
OIL TANK: ............................. 18.9 L (5 gallon) capacity
3.3VEHICLE SPECIFICATIONS
FUEL TANK: 18.9 L (5 gallon) capacity
WHEELS AND TIRES:
Front: 20-10 x 8.00 Tubeless Turfmate
Rear: 18-8.50 x 8.00 Tubeless Turfmate
TIRE PRESSURE: 10-12 PSI
FRAME: Welded steel construction
MOWING SPEED: 0- 12 K/H (0 - 7.5 MPH)
TRANSPORT SPEED: 12 K/H (7.5 MPH)
REVERSE SPEED: 3 K/H (2 MPH)
CONTROLS:
Foot operated traction pedal for forward and
reverse.
Hand operated choke and throttle levers.
Foot operated hydraulic lift with auto start/stop
feature.
Hand operated reel engagement lever.
Free-wheeling valve.
3.4BATTERY
TYPE: Group U1 Type GT
NOMINAL VOLTAGE: 12V
DIMENSIONS: L: 7-3/4(19.68 cm) x W: 5-3/16
(13.17 cm) x H: 7-5/16(18.5 cm)
3.5MOWER SPECIFICATIONS
NUMBER AND SIZE: 3  25" Reels
REEL DIAMETER: 7" (17.8 cm)
BEARINGS: Timken Tapered Roller
BLADES: Six Alloy Steel Blades
HEIGHT OF CUT: Adjustable: 1/2 to 2" (1.3 cm to
5.08 cm)
OVERALL CUTTING WIDTH: 70" (177.8 cm)
HEIGHT ADJUSTMENT: Roller Screw Adjustment
BEDKNIFE ADJUSTMENT: Screw adjustment of reel to
bedknife.
REEL FLOATATION: Front and Rear Roller with Cutting
Unit Center-line Pivot.
3.6WEIGHT & DIMENSIONS
OVERALL LENGTH: 86-3/8" (219.4 cm)
OVERALL HEIGHT: 44-3/4" (113.6 cm)
WHEEL BASE: 50-3/4" (128.9 cm)
WHEEL TREAD WIDTH: 45" (114.3 cm) (center of tires)
OVERALL WHEEL WIDTH: 55" (139.7 cm)
OVERALL WIDTH: 75" (190.5 cm)
WORKING WEIGHT: 1, 085 lbs. (492 kg)
3.7LUBRICANTS
ENGINE OIL:
Use high-quality detergent oil API (American
Petroleum Institute) service class SF. Select the
viscosity based on the air temperature at the time of
operation as shown in the table.
Recommended SAE Oil Viscosity Grades
HYDRAULIC SYSTEM OIL:
Use ISO GRADE 100 (SAE 30W) Hydraulic Oil

NATIONAL HYDRO 70" TRIPLEX
®
7
07406
07257
07405
07403
07372
07256
07404
NATIONAL MOWER CO.
700 RAYMOND AVE.
ST. PAUL, MINNESOTA 55114 USA
651-646-4079 FAX [phone]
POWER RATING: 9.7 kW at: 3200 rpm
WEIGHT: 528 kg
3.8DISPOSAL NUMBERS
Petrol, Lead Free: ....................... 54104
Engine oil: ................................... 54112
Fiberglass parts: ......................... 57103
Tires: ........................................... 57502
Gear oil: ...................................... 54112
Grease: ....................................... 54202
Plastic tanks: ............................... 57127
3.9NOISE EMISSION & VIBRATION
Sound: Operator Position, 88 dBA
Sound Power Level (LwA), 106 dBA
Vibration*: Max. Vibration, 57.7 m/s2 RMS
Location, Left Hand
Operating Condition: Engine rpm-3200, Unit stationary
3.10TRANSFERS

HY70OM-8/99
8
07408
07409 07407
TRANSFERS, Continued
3.11TRANSFER DESCRIPTION
07406 Do not exceed 25 degree slope. Located on main chassis.
07403 Parking brake on/off. Located on main chassis.
07372 Manufactures identification and specifications. Located on main chassis.
07257 Mowers up/reels off. Located on main chassis.
07256 Mowers down/reels on. Located on main chassis.
07405 Sound level at operators position. Located on main chassis.
07404 Sound power level. Located on main chasis.
07408 Mow pedal operation and vehicle motion pedal operation. Located on main chassis.
07409 Main instrument panel, Three wheel drive unit. Located on main chassis.
07407 Main instrument panel, Two wheel drive unit. Located on main chassis.

NATIONAL HYDRO 70" TRIPLEX
®
9
4ASSEMBLY INSTRUCTIONS
4.1ASSEMBLY
The Hydro 70 is shipped in two separate crates, one for
the tractor and one for the cutting units.
4.2TRACTOR ASSEMBLY
1. Disassemble crating for the tractor carefully to
prevent damage to components.
2. Remove the tape holding the keys in the steering
shaft. Position the handlebar assembly over the shaft
and key securing it with set screws provided it the
handle bar.
3. For removal of handle bar see Section 8.12.
4. Remove the tower cover. Refer to section 3.4 for
battery specifications. Install the battery on the base
inside the tower. Attach the red wire to the positive
terminal of the battery and attach the black ground wire
to the negative terminal of the battery. Replace and
secure the tower cover.
5. The seat base is temporally held together for
shipment. Remove and discard the fastener securing
the seat base to the spring plate. Position the seat
slider, which is assembled to the seat, onto the seat
base plate and secure with locknuts provided.
Attach the safety switch wires to the switch located
under the seat. Wires can be connected to either
terminal.
HANDLE BAR
KEY
COVER
6. Tires should be checked and if necessary adjusted for
proper inflation. Refer to Section 3.3.
7. Check the oil level in the oil tank. Refer to Section 8.10.
8. Check the oil level in the engine. Refer to 3.7 and 5.1.
4.3ASSEMBLY OF REAR CUTTING
UNIT TO TRACTOR
1. Disassemble crating for the cutting units carefully to
prevent damage to components.
2. Position the rear cutting unit under the tractor. The
rear cutting unit can be identified by the reel guard
attached the rear of the cutting unit. Position the cutting
unit with the reel pulley on the right side of the tractor.
Belt tool kit Part# 070008 is available
thru National Mowers parts department.
This tool will simplify the assembly of the
cutting units.
3. Remove the tie wrap holding the pull arm and spring
to the cutting unit. Assemble the pull arm to the tractor
using the sleeve and fastener provided.
NOTE
SEAT
SUPPORT

HY70OM-8/99
10
4. Remove the two top fasteners holding the pivot
bracket to the cutting unit and loosen the bottom
fastener so the bracket is free to rotate.
5. Align and assemble the spring and pull arm
previously attached to the tractor to the pull arm shaft on
the cutting unit. Place the belt on the cutting unit pulley.
With the pull arm assembled, rotate the pivot bracket
into place using it as a lever arm to compress the spring
and reattach with previously removed fasteners.
6. Assemble the pull rod on the left side of the cutting
unit to the tractor using fasteners provided.
7. A counterbalance spring has been assembled to the
tractor located under the steering tower. Remove the
spring bushing from the cutting unit making note of its
location. Insert the spring bushing into the spring loop,
pull directly down on the spring and reinsert the fastener
provided thru the bushing into the hole on the cutting
unit.
8. Remove the tie wraps securing the lift chains and
attach the chains to the lift arm under the tractor. One
chain per side.
ASSEMBLY OF REAR CUTTING UNIT, Con't.
PIVOT
BRACKET
PULL
ROD FRAME
PUSH ARM, SPRING
& SLEEVE
PUSH
ARM
SHAFT
9. Remove the tie wrap attaching the cutting unit belts
to the tractor. Position the cutting unit in front of the
tractor with the pulleys to the inside. Remove the two
top fasteners holding the pivot bracket to the cutting.
Place the belt on the cutting unit pulley. Assemble the
push arm to the pivot bracket using the washers and
snap ring provided. Rotate pivot bracket into place
using it as a lever arm to compress the spring and
reattach with previously remove fasteners.
10. Attach counterbalance spring and chains to lift bar.
11. Connect link bar between cutting units with
fasteners provided.
Belt tool, complete with instructions, (below) available
through National Mowers Parts Department.
LINK BAR
PUSH ARM
PIVOT BRACKET
PART # 070008