Nilfisk-Advance Advance SC750 Service Manual
  1. Manuals
  2. Brands
  3. Nilfisk-Advance Manuals
  4. Scrubber
  5. Advance SC750 ST
  6. Service manual

Nilfisk-Advance Advance SC750 Service Manual

Walk-behind scrubber nilfisk-advance advance: sc750, sc750 st, sc800, sc800 st/ nilfisk: sc800
Hide thumbs Also See for Advance SC750:
Table of Contents

Advertisement

Quick Links

See also: Instructions for Use Manual
Advance: SC750, SC750 ST, SC800,
SC800 ST
Nilfisk: SC800
Service Manual
Advance Models: 56112000(SC750-26D), 56112004(SC750-28D), 56112006(SC750-28C),
56112012(SC750 ST-26D), 56112013(SC750 ST-28C), 56112016(SC800-28D), 56112018(SC800-
28C), 56112024(SC800-32C), 56112028(SC800-34D), 56112032(SC800 ST-34D)
Nilfisk Models: 56112034(SC800-71), 56112035(SC800-86),
56112036(SC800-71C)
11/10 Form Number 56043150

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the Advance SC750 and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Nilfisk-Advance Advance SC750

Summary of Contents for Nilfisk-Advance Advance SC750

  • Page 1 Advance: SC750, SC750 ST, SC800, SC800 ST Nilfisk: SC800 Service Manual Advance Models: 56112000(SC750-26D), 56112004(SC750-28D), 56112006(SC750-28C), 56112012(SC750 ST-26D), 56112013(SC750 ST-28C), 56112016(SC800-28D), 56112018(SC800- 28C), 56112024(SC800-32C), 56112028(SC800-34D), 56112032(SC800 ST-34D) Nilfisk Models: 56112034(SC800-71), 56112035(SC800-86), 56112036(SC800-71C) 11/10 Form Number 56043150...

  • Page 2: Table Of Contents

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Contents General Information Service Manual Purpose and Application Other Reference Manuals Conventions Transporting the Machine Towing Cautions and Warnings General Safety Instructions General Machine Description Nameplate Know Your Machine Machine Specifications – SC750 and SC750 ST Machine Specifications –...
  • Page 3 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Parking Brake Laser Recovery System Functional Description Component Locations Troubleshooting Removal and Installation Specifications Special Tools Scrub System – Cylindrical Functional Description Component Locations Troubleshooting Removal and Installation Specifications Scrub System, Disc Functional Description Component Locations Troubleshooting...

  • Page 4: General Information

    This manual covers the Nilfisk SC800 models as well as Advance SC750, SC800, SC750 ST and SC800 ST models. Each ma- chine has as specific model number (part number) which can be found on its nameplate. The cover page of the manual lists each machine part number that the manual applies to.

  • Page 5: Other Reference Manuals

    Cautions and Warnings Symbols Nilfisk-Advance uses the symbols below to signal potentially dangerous conditions. Read this information carefully and take the necessary steps to protect personnel and property DANGER!

  • Page 6: General Safety Instructions

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST WARNING! Is used to call attention to a situation that could cause severe personal injury. Is used to call attention to a situation that could cause minor personal injury or damage to the machine or other prop- erty Read all instructions before using.

  • Page 7: General Machine Description

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST • Before performing any service function, carefully read all instructions pertaining to that function. • Do not leave the machine unattended without first turning the key switch off (O), removing the key and securing the machine • Turn the key switch off (O) and remove the key, before changing the brushes, and before opening any access panels...

  • Page 8: Know Your Machine

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Know Your Machine Control Panel – SC750 and SC800 (Membrane Switch Control Panel) These machines use a control panel with an LCD display in the center. See the following sections for switch identification, LCD Display explanations and Indicator Light explanations.
  • Page 9 Service Manual: SC750, SC800, SC 750 ST, SC800 ST • Scrub Pressure Increase Switch – Extends the scrub head actuator to apply additional scrubbing pressure on the floor (Disc models only). • Scrub Pressure Decrease Switch – Retracts the scrub head actuator to the normal scrub pressure position (Disc models only).
  • Page 10 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Indicator Lights All indicator lights illuminate for 2 seconds when the key is first turned on. Indicator Name Description • No flow = None lit Solution Flow Indicators • Low flow = Bottom one lit • Medium flow = Bottom two lit • High flow = All lit • Regular Scrub Pressure = Bottom one...
  • Page 11 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Control Panel – SC750 ST and SC800 ST (Toggle Switch Control Panel) These machines use a control panel with 3 large toggle switches and do not have an LCD display. See the following sec- tions for switch identification and Indicator Light explanations.
  • Page 12 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Indicator Lights All indicator lights illuminate for 2 seconds when the key is first turned on. Indicator Name Description • No flow = None lit Solution Flow Indicators • Low flow = Bottom one lit • Medium flow = Bottom two lit • High flow = All lit • Regular Scrub Pressure = Bottom one...

  • Page 13: Machine Specifications - Sc750 And Sc750 St

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Machine Specifications – SC750 and SC750 ST See other system chapters for specifications not listed here. Model Name/Model Number SC750 SC 750 ST Machine Voltage Volts Battery Capacity 242, 310, 312 Solution Tank Capacity Gal/L 21.33/80.7...

  • Page 14: Machine Specifications - Sc800 And Sc800 St

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Machine Specifications – SC800 and SC800 ST See other system chapters for specifications not listed here. Model Name/Model Number SC 800 SC800 ST Voltage, Batteries Battery Capacity 242, 310, 312 Solution Tank Capacity Gal/L 24.69 gal (93.5 l) Recovery Tank Capacity (Static)

  • Page 15: Machine Maintenance

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Machine Maintenance MAINTENANCE ITEM Daily Weekly Monthly Yearly Charge Batteries Check/Clean Tanks & Hoses Check/Clean/Rotate the Brush- es/Pads Check/Clean the Squeegee Check/Clean Vacuum Shut-Off Float Empty/Clean Debris Tray In Re- covery Tank Clean Hopper on Cylindrical System Check Each Battery Cell(s) Water...
  • Page 16 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Lubricating the Machine Once a month, apply light machine oil to lubricate the: • General Pivot Points for the Squeegee Linkage (A). • Squeegee mount angle adjustment knob threads (B). • Squeegee Tool end wheels (C). • General Pivot Points for the Brush Linkage (D).

  • Page 17: Chassis System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Chassis System Functional Description The chassis is made up of heavy gauge steel and supports the drive transaxle, caster wheel, brush deck, squeegee assem- bly and machine body Form Number 56043150 Page 17...

  • Page 18: Control System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Control system Functional Description There are two controllers on the machine, a Main Machine Controller and a Drive Motor Controller The Main Machine Controller operates the floor cleaning functions of scrub, solution and vacuum based on operator requests and other inputs.

  • Page 19: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Electrical Panel Cover • Circuit Breaker Mounting Plate • Control Switch Interface Panel • Main Machine Controller Form Number 56043150 Page 19...

  • Page 20: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Fault Codes SC750 and SC800 models - Any error codes detected by the Main Machine Controller will be displayed on the LCD display as they occur SC750 ST and SC800 ST models – Active faults are displayed as a blink code on the fault code indicator light. The code will be a two digit code.
  • Page 21 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Code Explanation / Code Setting Conditions / Flash Indicator / Disables / Check Display Blink Definition Code Code Brush Motor Circuit Excessive current draw was sensed. Code sets at approxi- Over Current mately 60 amps or more.
  • Page 22 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Code Explanation / Code Setting Conditions / Flash Indicator / Disables / Check Display Blink Definition Code Code Scrub Deck Lift Actuator The Main Machine Controller is trying to move the actua- Circuit Open tor but it is not sensing any current flow.
  • Page 23 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Code Explanation / Code Setting Conditions / Flash Indicator / Disables / Check Display Blink Definition Code Code Solution Solenoid Circuit The Main Machine controller is sensing current flow Stuck On through its internal switch for the solution solenoid cir- cuit when it has not requested that the switch be turned on.
  • Page 24 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Service Test Mode Some outputs (like the scrub brush motors) are only turned on when other conditions are met, such as when the ma- chine is moving. It can be difficult to check for voltage to the scrub brush motors while the machine is moving. Also, if voltage is not present, it leaves in question what other conditions may not have been met yet.
  • Page 25 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Input Tests Speed Control Forward/Reverse Signal –The yellow Battery LED turns on when in the service test mode whenever the speed controller tells the Main Machine Controller that it is attempting to drive the machine either forward or reverse. This is useful when diagnosing a no drive problem.
  • Page 26 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Solution Solenoid – Press the Solution Switch to cycle the solution solenoid on and off. Listen for the Solenoid to click on and off. Press the switch again to stop cycling the solenoid. The LCD display for “SOL” will show “On” as long as the test mode is running;...
  • Page 27 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Programming Options –SC750 ST and SC800 ST Models (control panel with rocker switches) Main Machine Controller special program options allow the service repairperson to match the control board to the specific model equipment and to user preferences. They also allow adjustments to some machine functions, and provide a way to see the controller’s revision level.
  • Page 28 Service Manual: SC750, SC800, SC 750 ST, SC800 ST • 4 blinks = On-board charger with GEL EXIDE 25A batteries • 5 blinks = On-board charger with GEL-AGM 25A batteries • 6 blinks = On-board charger with WET 15A batteries • 7 blinks = On-board charger with GEL-AGM 15A batteries Additional Program Options The following options can be used by the technician or to set user preferences.
  • Page 29 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Lock Out Solution Flow Rate - It is possible to lock out any one or more of the solution flow rate settings. During normal operation, the flow rate(s) that are locked out will not be able to be selected. To check or change the setting: While pressing and holding the vacuum and solution switches forward and the scrub switch backwards, turn the key switch on...
  • Page 30 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Restore Factory Defaults – This function is used to reset all settings to factory default values. If this is done, the next time the key is turned on, it will act as though a new controller has been installed and “force” you to set the mandatory program options before the machine will operate normally.
  • Page 31 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Software Revision Code – This function is used to display the software revision. The Fault LED blinks a two-part code to indicate the revision of the software that is currently programmed into the microcontroller program memory. The first part of the code indicates the released revision letter: 1 blink = revision A, 2 blinks = revision B, etc.
  • Page 32 “Americas market” (North, South and Central America). Global mode: (Outside of North, South and Central America) Shows chemical ratio using percentage notation (example 0.3%) and the “Nilfisk-Advance” brand upon power up. In off mode, the chemical icon and ratio are not displayed on the LCD.
  • Page 33 Service Manual: SC750, SC800, SC 750 ST, SC800 ST DETERGENT MODE – This function is used to configure the way the EcoFlex system behaves or to disable it. Different geographic locations desire different EcoFlex behavior. This mode provides the ability to match the behavior to market area desires • OFF –...
  • Page 34 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Additional Program Options The following options can be used to set user preferences. LOCKOUT BRUSH PRE - - For disc brush decks only, it is possible to lock out either the Low or High Brush Pressure setting. During normal operation the pressure setting(s) that are locked out will not be able to be selected.
  • Page 35 Service Manual: SC750, SC800, SC 750 ST, SC800 ST CHEMICAL RATE BIAS – This function allows a fine tuning of the detergent ratio. • NONE • +10% MORE CHEMICAL • -10% LESS CHEMICAL To change the setting: Scroll through the menu using the Solution Increase and Decrease switches until you get to the desired value. To save and go back to the main menu, press the scrub ON/OFF switch.

  • Page 36: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Main Machine Controller SC750 ST and SC800 ST Models (Control Panel with rocker switches) Note: Electronic devices like the Main Machine Controller are sensitive to Electrostatic Discharge (ESD). Before handling the controller, touch a metal bench or shelf to discharge any electrical charge that may have built up in your body.
  • Page 37 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Tip cover away from machine and disconnect electrical connectors from the Main Machine Controller and Key Switch. Remove the control switch interface panel ground screw. Place electrical panel cover on work bench Remove 4 screws securing circuit board (Main Machine Controller) to cover.
  • Page 38 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Main Machine Controller SC750 and SC800 Models (Control Panel with membrane switches) Note: Electronic devices like the Main Machine Controller are sensitive to Electrostatic Discharge (ESD). Before handling the controller, touch a metal bench or shelf to discharge any electrical charge that may have built up in your body. Do not walk around with a controller in your hands Completely drain solution tank.
  • Page 39 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Remove electrical panel cover mounting screws. Tip cover away from machine and disconnect the clear pressure sensor hose from the fitting at the solution tank. DO NOT TRY TO DISCONNECT THE HOSE FROM THE CIRCUIT BOARD. Disconnect electrical connectors from the Main Machine Controller and Key Switch.
  • Page 40 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Remove the electrical panel cover and place on a work bench Remove the 5 screws securing the switch panel interface and carefully turn the cover over. 10. Remove 4 screws securing circuit board (Main Machine Controller) to cover. Be careful not to lose the 4 plastic spacers that go between the circuit board and the cover.

  • Page 41: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Specifications Shop Measurements – Main Machine Controller The following tables contain some “real world” shop voltage measurements to help you recognize what “normal” looks like. All voltage values were measured with the black (Negative) voltmeter lead connected to the main battery negative terminal unless otherwise specified.
  • Page 42 Service Manual: SC750, SC800, SC 750 ST, SC800 ST J2 Connector Used on Non Pin # Circuit Description Value Comments ST or ST 1 Battery Negative (Ground) 0.5mV With vacuum motor running Both 2 Battery Negative (Ground) 0.5mV With vacuum motor running Both 3 Input from Brush Deck actua- 4 95V...
  • Page 43 Service Manual: SC750, SC800, SC 750 ST, SC800 ST J3 Connector Used on Non Pin # Circuit Description Value Comments ST or ST 1 Battery “+“ lead 24.0v With vacuum motor running Both 2 Battery “-“ lead 0.5mV With vacuum motor running Both 3 Brush Remove contactor output 28mV...

  • Page 44: Electrical System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Electrical System Functional Description General The electrical system is powered by four 6 volt batteries for a total of 24 volts. Heavy cables connect the batteries in series. A large red Main Battery Pack Connector provides battery power to the machine wiring. On machines without an on-board battery charger, the Main Battery Pack Connector is used for hooking up the batteries to a “shelf”...
  • Page 45 Service Manual: SC750, SC800, SC 750 ST, SC800 ST On-board Battery Charger An optional on-board battery charger is available. When equipped, it is mounted on the bottom of the machine. The charger has an internal relay that interrupts power to the on-board when the charger is plugged into an AC power outlet. This is called the “Interlock”...
  • Page 46 Service Manual: SC750, SC800, SC 750 ST, SC800 ST When the battery charger is plugged in, the machine will display the type of battery charge profile in use as well as charg- ing progress. SC750 and SC800 models use the LCD display to describe the charging profile in words, and a battery icon with 0 to 5 bars, to show the charging progress.

  • Page 47: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Batteries • Main Battery Pack Connector • Battery Charger (Optional) • Electrical Panel • Main Fuse • Battery Negative Stand Off • Circuit Breakers Form Number 56043150 Page 47...

  • Page 48: Maintenance And Adjustments

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Maintenance and Adjustments Battery Maintenance and Recharging See Instructions for Use Manual Troubleshooting Insufficient Machine Operation Time Possible Causes: • Incorrect low-voltage cutout setting • Batteries not fully charged. o If there is any question whether the batteries are fully charged, they should be charged for at least 16 hours • One or more weak batteries o To determine if one of the batteries is weak, measure the voltage across each individual battery while...

  • Page 49: Removal And Installation

    CAUTION! Electrical components in this machine can be severely damaged if the batteries are not installed and connected properly. Only Nilfisk-Advance, a qualified electrician, or the battery manufacturer should install batteries. Empty the recovery tank and tip it up. Turn the key switch off and disconnect the main battery pack connector.

  • Page 50: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Battery Charger (Optional On-board Battery Charger) The battery charger is mounted to the bottom of the frame with 4 bolts that are screwed into threaded holes. Cut tie straps securing AC power cable. Cut tie straps securing electrical connectors.

  • Page 51: Wiring Diagram (Electrical Schematic) - Complete Machine Sc750 And Sc800

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wiring Diagram (Electrical Schematic) – Complete Machine SC750 and SC800 The first page is a “complete” view. When viewing on a computer it can be enlarged to be legible while retaining the convenience of a single page.
  • Page 52 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 52...
  • Page 53 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 53...

  • Page 54: Wiring Diagram (Electrical Schematic) - Complete Machine Sc750 St And Sc800 St

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wiring Diagram (Electrical Schematic) – Complete Machine SC750 ST and SC800 ST The first page is a “complete” view. When viewing on a computer it can be enlarged to be legible while retaining the convenience of a single page.
  • Page 55 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 55...
  • Page 56 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 56...

  • Page 57: Wiring Harness Configuration Diagram - Sc750 And Sc800

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wiring Harness Configuration Diagram – SC750 and SC800 The first page is a “complete” view. When viewing on a computer it can be enlarged to be legible while retaining the con- venience of a single page.
  • Page 58 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 1 of 4 Form Number 56043150 Page 58...
  • Page 59 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 2 of 4 Form Number 56043150 Page 59...
  • Page 60 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 3 of 4 Form Number 56043150 Page 60...
  • Page 61 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 4 of 4 Form Number 56043150 Page 61...

  • Page 62: Wiring Harness Configuration Diagram - Sc750 St And Sc800 St

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wiring Harness Configuration Diagram – SC750 ST and SC800 ST The first page is a “complete” view. When viewing on a computer it can be enlarged to be legible while retaining the con- venience of a single page.
  • Page 63 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 1 of 3 Form Number 56043150 Page 63...
  • Page 64 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 2 of 3 Form Number 56043150 Page 64...
  • Page 65 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Page 3 of 3 Form Number 56043150 Page 65...

  • Page 66: Options And Accessories

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Options and Accessories Battery Fill Indicator The Battery Fill Indicator provides a quick visual indication of when one of the battery cells is low and needs water added. It is installed in place of one of the battery fill caps. The wire lead goes to the battery negative terminal. When the level is Okay, the green LED is lit.

  • Page 67: Hour Meter

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Hour Meter The hour meter keeps track of the run time of the scrub motors. On-board Battery Charger An optional on-board battery charger is available. It attaches to the bottom of the machine. See the Electrical System chapter for more information.
  • Page 68 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 68...

  • Page 69: Parking Brake

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Parking Brake The optional parking brake kit has a manually operated lever that presses a plunger against a drive wheel to act as a brake Laser The laser provides a visual cue of the cleaning path width and provides an early warning that a machine is approaching. Form Number 56043150 Page 69...

  • Page 70: Recovery System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Recovery System Functional Description The job of the recovery system is to remove the dirty water from the floor and store it in the recovery tank. The dirty water is then disposed of. Dirt and water are lifted off the floor into the recovery tank by airflow created by a vacuum motor.

  • Page 71: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST The vacuum contactor (relay) is turned on when the following inputs are met: • Operator request o Scrub On/Off switch has been pressed or o Vacuum/Wand switch has been pressed • Machine Moving Signal is received from the Drive Motor Controller The vacuum relay is de-energized when the operator turns off the scrub system following a timed delay.

  • Page 72: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Vacuum Motor Does Not Turn On (Scrub function works) Possible Causes: • Defective Vacuum Motor • Defective Vacuum Motor Contactor (Relay) • Defective Wiring • Defective Insufficient Water Pickup Good water pick up performance depends on the proper amount of air flowing through the squeegee pickup tool. Air entering the vacuum system before the pickup tool will reduce its ability to pick up water.
  • Page 73 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Hold the vacuum gauge against the end of the hose and turn on the vacuum motor. Note the reading on the gauge. If it is within 10% of specs, go to the next step. If it is too low, check for air leaks in the system. Install a one inch open-hole adapter between the hose end and the vacuum gauge.

  • Page 74: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Vacuum Motor Turn off key switch, drain recovery tank and lift recovery tank up. Cut tie straps securing wiring and disconnect vacuum motor electrical connection. Remove vacuum motor cover mounting screws and cover. Note: The vacuum motor cooling fan guard may come off the end of the motor.
  • Page 75 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Remove vacuum motor and foam pieces. Pay attention to how the foam pieces are positioned. Reassemble in reverse order Install the cooling fan guard if it is not in place. Take care to position all the foam pieces correctly. Make sure the ends of the vacuum motor are seated correctly.

  • Page 76: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Specifications Vacuum Motor .66 HP (490 watt) three-stage Vacuum Performance: • Blocked off - measured at squeegee hose end 51.2“ H20 minimum • With 1 inch hole measured approximately 8.7” H2O minimum Vacuum Motor Amp Draw With everything assembled and squeegee off the floor - 17 Amps Special Tools...

  • Page 77: Scrub System - Cylindrical

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Scrub System – Cylindrical Functional Description The scrub system moves the scrub head up and down and turns the scrub motors on and off at the operator’s request, to provide floor scrubbing action. The brushes spin toward one another at the bottom. The head is moved up and down by an electric actuator motor that has integrated position switches.
  • Page 78 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Here is how the circuit works for the actuator. The Main Machine Controller directly drives the brush head actuator mo- tor. It applies system voltage across the two actuator motor wires to move the motor up. It reverses polarity to move the motor down.
  • Page 79 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 79...

  • Page 80: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Brush Contactor • Brush Drive Motor • Brush Head • Motor Drive Pulley • Debris Hopper • Brush Drive Pulley • Idler Assembly • Brush Drive Belt • Brush Head Actuator Form Number 56043150 Page 80...
  • Page 81 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 81...

  • Page 82: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Scrub Motors Do Not Turn On Possible Causes • Brush Contactor o Open or shorted winding o Burned contacts • Wiring • Main Machine Controller – Not energizing the brush contactor. • Drive Motor Controller –...
  • Page 83 Service Manual: SC750, SC800, SC 750 ST, SC800 ST • Drive the actuator motor all the way up and down using jumper wires powered by bat- tery positive and negative. Connect them to the two actuator motor wires at the Main Machine Controller connector.

  • Page 84: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Scrub Brush Turn the key switch off and wait for the Brush Head to rise. Disconnect the Battery Pack Connector. Loosen the hand wheel nut several turns until the idle cover lowers far enough that the slots clear and allow the cover to be pulled outward If the cover is stuck, push down on the hand wheel Pull brush out of housing.
  • Page 85 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Slide new brush into housing. Rotate and lift the end to engage the drive hub flanges with the slots in the end of the brush Position idler pulley in brush end and seat the idler cover flat against the brush head Tighten the hand wheel nut, making sure that the slots in the idle cover line up and engage the brush head.
  • Page 86 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Brush Drive Belt The drive belt is a “stretch belt” and may appear “too short”. It is not tensioned with a slotted adjustment but instead is stretched on much like a vacuum cleaner belt Remove belt cover Pry the brush drive belt off the drive motor pulley using a screw driver.
  • Page 87 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Brush Head Actuator. Empty recovery tank. Press the scrub button to lower the brush head. If the actuator does not move, slightly raise the brush head with a jack to take tension off of the mounting hard- ware Lift recovery tank up.
  • Page 88 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Brush Motor Remove the rear Scrub Brush Remove the Debris Hopper. Remove the Brush Drive Belt Lower Brush Head. Reconnect Battery Pack Connector. Turn the key on, press the scrub switch and wait for brush head to lower Unplug Brush Head Actuator electrical connector, turn the key off and unplug the Battery Pack connector.
  • Page 89 Service Manual: SC750, SC800, SC 750 ST, SC800 ST 10. Partially remove motor for better access to the wiring terminals. 11 Do not lose the spacer plate 12 Record the wiring connections so that you will be able to reconnect it properly upon reassembly. 13 Remove wiring.
  • Page 90 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Motor Carbon Brushes Remove the brush drive motor Mark the position of the endplate to the motor casing for reassembly. Remove the 2 through bolts and pry off the endplate assembly. Replace the carbon brushes Observe how the springs roll when the brush is pushed back before taking it apart.
  • Page 91 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Push brush back against the spring and insert a stiff temporary retaining wire (paper clip) through the ac- cess hole in the end cover. (Remove silicone sealer from the holes) The wire must go through the holes in the brush holder just in front of the brush to hold the brush back against the spring pressure.

  • Page 92: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Specifications Scrub Motor Total Amp Draw Typical total amp draw for both 28 inch and 32 inch decks ranges from 45 Amps to 65 Amps when scrubbing with low solution flow, depending on the type of floor. Scrub Motor Speed 830-840 RPM Scrub Force...

  • Page 93: Scrub System, Disc

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Scrub System, Disc Functional Description Scrubbing The scrub system moves the scrub head up and down and turns the scrub motors on and off at the operator’s request to provide floor scrubbing action. The discs spin toward the center at the front edge of each disc. The head is moved up and down by an electric actuator motor that has integrated position switches.
  • Page 94 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Here is how the circuit works for the actuator. The Main Machine Controller directly drives the brush head actuator motor. It applies system voltage across the two actuator motor wires to move the motor up. It reverses polarity to move the motor down.
  • Page 95 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 95...
  • Page 96 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Brush Disc Remove Feature The brush disc remove feature spins the brushes and then brings them to an abrupt stop to release the brushes from the brush plate retaining springs. To accomplish this, a series of events takes place. Step #1 First the Main Machine Controller checks to make sure that the scrub deck is fully raised, the charger is not plugged in and that the machine is not moving.
  • Page 97 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Step #3 Next the brush motor relay is de-energized. This removes the battery positive power source from the motor AND instead connects the motor to battery negative through the normally closed contacts. The motor stops abruptly when both sides are connected to battery negative.

  • Page 98: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Brush Head (Deck) • Brush Plate • Brush Motor • Gas Spring • Brush Head Actuator • Brush Contactor Form Number 56043150 Page 98...

  • Page 99: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Scrub Motors Do Not Turn On Possible Causes • Brush contactor o Open or shorted winding o Burned contacts • Wiring • Main Machine Controller – Not energizing the brush contactor. • Drive Motor Controller –...
  • Page 100 Service Manual: SC750, SC800, SC 750 ST, SC800 ST  Check the middle position switch. • Put the black ohmmeter lead on the Brown wire at the J2 connector pin 2 • Put the red ohmmeter lead on the Yellow wire at the J2 connector pin 11 • Drive the actuator motor all the way up and down using jumper wires powered by bat- tery positive and negative.

  • Page 101: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Scrub Brush Brush Head Remove plastic brush head covers. Remove scrub brushes Loosen, but do not remove the 3 brush head mounting fasteners. Turn the key on and press the scrub on/off button to lower the brush head to the floor. Then turn the key off leaving the brush head on the floor.
  • Page 102 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Scrub Motor Carbon Brushes Note: Photos in this section were taken with the motor removed from the machine for better clarity. Remove the plastic motor cover. Remove wiring from motor connectors. Remove one of the round plastic brush caps using a large slotted screw driver.
  • Page 103 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Brush Head Actuator Empty recovery tank. Press the scrub button to lower the brush head. If the actuator does not move, slightly raise the brush head with a jack to take tension off of the mount- ing hardware.

  • Page 104: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Specifications Scrub Motor Amp Draw No Load - Approximately 4 Amps Scrub Motor Total Amp Draw Total amp draw in regular scrub mode with low solution flow for all size decks ranges from 15-30 Amps depending on the floor surface.

  • Page 105: Solution System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Solution System Functional Description The solution system dispenses water and detergent to the scrub brush head for scrubbing the floor. The solution tank holds the solution and serves as the main body of the scrubber. Solution from the tank flows through a manual shut off valve, filter, solution valve (solenoid), manifold and out to the deck.
  • Page 106 Service Manual: SC750, SC800, SC 750 ST, SC800 ST machine has the optional detergent mixing system, the Main Machine Controller also operates the additional detergent pump The two wires for the pump are wired directly to the Main Machine Controller The Main Machine Controller sup- plies battery positive on one wire and battery negative on the other for a short period of time to stroke the piston in one direction.

  • Page 107: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Solution tank • Shut off valve (Ball Valve) • Solution filter • Solution solenoid valve • Detergent pump • Detergent tank • Solution drain hose Form Number 56043150 Page 107...

  • Page 108: Maintenance And Adjustments

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Maintenance and Adjustments Solution Filter Cleaning Work near a floor drain for convenient clean up if possible Turn the key switch off. Close the shut off valve (The valve is closed when the lever is NOT in line with the hose).

  • Page 109: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Insufficient Solution Flow Possible Causes • Restricted solution filter • Debris/sludge in solution tank clogging fitting to shut off valve • Pinched hose • Restricted solution valve Solution Leaks After Machine Is Shut Off Possible Causes • Solution valve not sealing (Worn or debris holding it open.) • Hose or fitting leak before solution valve...

  • Page 110: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Solution Valve Work near a floor drain for convenient clean up if possible. Turn the key switch on and lower the brush head by pushing the Scrub On/Off switch. Unplug the deck actuator to prevent deck from rising.

  • Page 111: Specifications

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Remove control panel cover Disconnect wiring from electrical components on electrical panel. 10. Disconnect the pressure sensor hose at the solution tank end. 11 Thread wiring out of solution tank. 12 Remove squeegee lift cable. 13 Remove solution tank shut off valve elbow from tank.

  • Page 112: Squeegee System

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Squeegee System Functional Description The squeegee collects the water so that the recovery system vacuum can suck it up off the floor and store it in the recov- ery tank. The squeegee support is spring loaded downward to push the squeegee against the floor, and has a pivot point that allows the squeegee to “swing”...

  • Page 113: Maintenance And Adjustments

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Maintenance and Adjustments Adjusting Squeegee Tilt The tilt of the squeegee causes the rear blade to rise up in the center or on the ends, depending on which direction the tilt is changed. Park the machine on a flat, even surface and lower the squeegee.
  • Page 114 Service Manual: SC750, SC800, SC 750 ST, SC800 ST defeating the breakaway feature. Squeegee Support Remove squeegee tool. Remove squeegee lift cable from support. Service Tip: The force of the springs against the pivot bolt causes it to tip backwards and makes it difficult to get the assembly removed and back into place.
  • Page 115 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Tighten the tension strap screw. Rear Squeegee Blade Remove squeegee tool. Unsnap the center latch. Remove the tension straps Remove the blade Install blade on tool, being careful to match the alignment slots. Install the tension straps Snap the center latch closed Form Number 56043150...

  • Page 116: Wheel System Non-Traction

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wheel System Non-Traction Functional Description A single caster wheel mounted to the back of the frame allows the machine to pivot easily. The wheel is attached with 4 bolts that are screwed into threaded holes in the frame Component Locations • Caster Wheel Form Number 56043150...

  • Page 117: Wheel System, Traction

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Wheel System, Traction Functional Description A permanent magnet motor transaxle is used to propel the machine in both forward and reverse directions. The con- trols for forward, reverse and speed are different between the “ST” (SC 750 ST, SC800 ST) and “Non-ST”(SC750, SC800) Models.
  • Page 118 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Form Number 56043150 Page 118...
  • Page 119 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Drive Motor Controller Outputs The primary job of the Drive Motor Controller is to operate the electric transaxle drive motor. It does this by regulating current flow through the drive motor to control speed, and by changing polarity to control direction. The secondary job is to notify the Main Machine Controller when the machine is moving and which direction it is moving.
  • Page 120 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Drive Motor Circuit Description - SC750 and SC800 models. Form Number 56043150 Page 120...
  • Page 121 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Powering up the Drive Motor Controller: This is the same as the “ST” models. See above section. Drive Motor Controller Inputs To drive forward, the operator pushes on a drive paddle which rotates the Speed Control Potentiometer inside the paddle.

  • Page 122: Component Locations

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Component Locations • Transaxle • Drive Motor Controller Form Number 56043150 Page 122...
  • Page 123 Service Manual: SC750, SC800, SC 750 ST, SC800 ST • Speed Limit Potentiometer – SC750 and SC800 • Drive Paddle Position Sensor – SC750 and SC800 • R4 Resistor - ST • Speed Limit Potentiometer –ST • Palm Drive Switches - ST • Reverse Switch –...

  • Page 124: Troubleshooting

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Troubleshooting Does Not Propel Forward or Reverse Possible Causes • Battery voltage too low • Controller not receiving input requests for travel • Drive motor • Drive motor controller • Wiring If the drive system is not functional but the rest of the machine control panel operates, use the Service Test Mode to speed your diagnosis.

  • Page 125: Removal And Installation

    Service Manual: SC750, SC800, SC 750 ST, SC800 ST Removal and Installation Speed Limit Potentiometer – ST models Loosen set screw and remove knob Remove potentiometer mounting nut and washer. Remove upper handle bolts Loosen lower handle bolts and rotate handle down Disconnect handle electrical connector Remove the access plate...
  • Page 126 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Palm Button Switches – ST models Remove two switch mounting screws. Remove upper handle bolts Loosen lower handle bolts and rotate handle down Disconnect handle electrical connector Remove access plate Disconnect wiring. Remove switch and wiring.
  • Page 127 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Paddle Position Sensor – Non-ST models - SC750, SC800 Photos are shown working on a bench top but this can be done on the machine. Remove top two handle mounting bolts. Loosen the bottom two handle mounting bolts and rotate handle down.
  • Page 128 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Install the potentiometer. Loosely install the potentiometer fork. 10. Install the cam controller inserting the pin end into the fork. 11 Adjust the potentiometer position. Measure the resistance between the two outer terminals and write the value down Hook up your ohmmeter leads between the center terminal and one of the outer terminals.
  • Page 129 Service Manual: SC750, SC800, SC 750 ST, SC800 ST 13 Reinstall the paddle cover. (Reconnect the speed limit potentiometer wiring.) 14 Rotate the handle assembly back up into position and loosely install the top mounting bolts. 15 Tighten all 4 handle mounting bolts. Paddle Centering Springs - Non-ST models - SC750, SC800 In the event that the paddle centering springs and hardware need to be replaced, these photos will help you assemble it correctly...
  • Page 130 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Next, prepare the upper stack for assembly as shown. Install it and tighten the screw. (Do not over-tighten the screw or it will strip out the tower). Drive Wheel Loosen the three nuts securing the wheel to the hub flange. There are 6 nuts on the outer rim of the wheel.
  • Page 131 Service Manual: SC750, SC800, SC 750 ST, SC800 ST With the help of an assistant, lay the machine on its side. Lay it on the side that has the wheel off and be sure to protect the side from damage. Remove the other drive wheel and the transaxle mounting bolts behind it.
  • Page 132 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Transaxle Drive Motor Carbon Brushes Remove transaxle. Remove round black plastic brush cap. Remove carbon brush and spring. Install brush and spring. Install and tighten cap with a screwdriver. Repeat steps for all 4 carbon brushes Form Number 56043150 Page 132...
  • Page 133 Service Manual: SC750, SC800, SC 750 ST, SC800 ST Specifications Drive Wheels Diameter: 10 in (25.4 cm) Width: 3 in (7.62 cm) Type/Material: Polyurethane Foam - molded Drive Motor .4 HP (298 watts) Max. Transport Speed Fwd: 5.75 km/h (3.57 mph) Rev: 4.36 km/h (2.71 mph) Drive Motor...

This manual is also suitable for:

Advance sc800 stSc750Sc800Sc800 st

Table of Contents

Save PDF