Bobcat 743 Specifications & Workshop Service Guide

The Bobcat 743 is a skid steer loader produced during 1981-1993, powered by a 36-horsepower Kubota V1702 4-Cyl Diesel diesel engine. It features an operating weight of 4,720 lbs (2,141 kg), a rated operating capacity of 1,300 lbs (590 kg, SAE J818), and an auxiliary hydraulic flow of 15.5 GPM at 2350 PSI (21.2 HHP).

Bobcat 743 (1981-1993) Field Service Dossier

Wheeled Skid Steer Loader
1,300 lbs ROC 4,720 lbs Weight 36 HP
SAE J818 Verified
⚠️ Report Discrepancy

Engine & Powertrain

Engine Model
Kubota V1702 4-Cyl Diesel
Gross Output
36 HP
Crankcase Oil
8.5 qts (15W-40 Heavy Duty Diesel (API CK-4))
Cooling System
11.5 qts (50/50 Ethylene Glycol)

Hydraulic Circuit & Flow

Auxiliary Flow
15.5 GPM (Standard Flow)
Relief Pressure
2350 PSI
Hydraulic HP
21.2 HHP (GPM × PSI / 1714)
Reservoir Capacity
8.0 US Gal (ISO VG 46 / SAE 10W-30 Motor Oil with ZDDP)
Total System Vol
10.5 US Gal (Includes cylinders)
Drive Chain Case
6.0 US Gal (SAE 10W-30 or 10W-40 Motor Oil (API Service CD/CE/CK-4))

Wix / Donaldson OEM Filter Cross-Reference

Engine Oil Filter Wix 51064 / Donaldson P550086
Hydraulic Filter Wix 51567 / Donaldson P550388
Primary Fuel Filter Wix 33397 / Donaldson P550385
Outer Air Filter Wix 42222 / Donaldson P181050
Chassis Stamp Serial Location: Stamped on upright cab support plate behind operator right shoulder and stamped on lower left frame above left drive wheel.
OEM Service Manual Factory Source: Melroe / Bobcat Workshop Service Manual Pub #6566109 (Section 10-01)
ASE Certified Master Technician 24h Field Verification SLA

Heavy Equipment Hydrostatic & Powertrain Desk

Factory OEM Technical Manuals • Hydrostatic Telemetry Standards

All fluid capacities, relief pressure ratings, and Rated Operating Capacities (ROC) on SkidSteerSpecs.online are verified against physical factory OEM workshop manuals. We validate that pump cavitation tolerances, hydrostatic charge pressures, and separate chain case sumps adhere strictly to manufacturer service bulletins.

Primary Factory Service Manual Citations:
BOBCAT Pub #6566109 • Sec 10-01 (Hydraulics)
CAT OMM SEBU9084-04 (259D3 / 289D)
KUBOTA WSM-10491 (Common Rail & SSV/SVL)
CASE CE Manual #8-42211 (Tandem Hydro Pumps)
Wheel Lug Torque: 145 ft-lbs (197 N•m)
Charge Pressure: 350 ± 50 PSI
Filter Bypass: 25 PSI Differential
Chain Deflection: 0.25 in (6.3 mm)

Bobcat 743 Workshop Manual & Kubota V1702 Service Dossier

Vintage Bobcat 743 skid steer loader parked in equipment workshop with rear tailgate open revealing Kubota diesel engine AI Visual
Bobcat 743 compact loader undergoing routine 100-hour engine service in an equipment maintenance bay with Kubota V1702 diesel exposed.
Vintage Workhorse Engineering

Complete Bobcat 743 Factory Technical Specifications & Drivetrain Architecture

Produced by Melroe / Bobcat in Gwinner, North Dakota between 1981 and 1993, the Bobcat 743 remains the most reliable mechanical-injection compact loader in agricultural and excavation history.

What engine powers the Bobcat 743, and what are its performance specifications?

Direct Answer: The Bobcat 743 is powered by a Kubota V1702 4-cylinder, naturally aspirated, liquid-cooled indirect-injection diesel engine. It displaces 105.7 cubic inches (1.73 Liters), producing 36 gross horsepower at 2,800 RPM and 78 ft-lbs of peak torque at 1,800 RPM.

Engine Bore, Stroke & Compression

The Kubota V1702 features an 82 mm (3.23 in) cylinder bore and an 82 mm stroke with a 21:1 compression ratio. It relies on a mechanical Bosch-style MD mini-pump injection system with pintle glow plugs that require 10 to 15 seconds of pre-heating in sub-freezing ambient conditions.

Oil Capacity & Service Interval

The engine crankcase holds 8.5 US quarts (8.0 Liters) of heavy-duty diesel engine oil including the spin-on filter. Factory intervals dictate 100-hour oil changes using API CK-4 or CJ-4 15W-40 (or 10W-30 for winter plowing).

What are the physical dimensions, lift height, and turning radius of the Bobcat 743?

Direct Answer: The Bobcat 743 measures 120.4 inches (3,058 mm) in length with standard 54-inch dirt bucket, 55.1 inches (1,400 mm) in width, and 75.8 inches (1,925 mm) in height to the top of the ROPS cab. It achieves a maximum bucket pin hinge height of 109.0 inches (2,769 mm).

Dimensional Metric US Customary (Imperial) Metric (SI) Operational Clearance Note
Operating Weight 4,720 lbs 2,141 kg With standard 54" bucket, full fluids & 165 lb operator
Rated Operating Capacity (ROC) 1,300 lbs 590 kg Strictly 50% of static tipping load (SAE J818)
Tipping Load 2,600 lbs 1,179 kg Threshold where rear tires break ground contact
Hinge Pin Height (Full Lift) 109.0 inches 2,769 mm Clears standard tandem dump truck sideboards
Wheelbase Length 35.4 inches 899 mm Compact turning radius of 72.8 inches with bucket
Ground Clearance 7.1 inches 180 mm Center frame belly pan clearance

What fluids and capacities are required for a complete Bobcat 743 service?

Direct Answer: A full dry service requires 8.0 gallons of ISO VG 46 hydraulic fluid, 6.0 gallons of SAE 10W-30 motor oil for the independent chain case, 8.5 quarts of 15W-40 for the engine, and 11.5 quarts of 50/50 ethylene glycol coolant.

Before pouring fluid, mechanics must verify which reservoir is being filled. Read our full skid steer hydraulic fluid cross-reference guide to understand why pouring hydraulic oil into the chain case causes severe drive chain stretch. If running hydraulic attachments like augers or trenchers, Calculate attachment compatibility for the 743's 11 GPM standard flow circuit. You can also compare the 743 against modern loaders in our Universal Skid Steer Spec & Capacity Engine.

How do you troubleshoot steering lever creep and fuel shutoff issues on a 743?

Direct Answer: Steering lever creep (where the machine slowly walks forward or backward when hand levers are in neutral) is resolved by adjusting the hydrostatic pintle centering springs on the steering linkage rods located directly beneath the operator seat.

Steering Lever Creep Adjustment

Elevate the machine securely on jackstands with all 4 wheels off the ground. Loosen the jam nuts on the neutral centering spring brackets on both sides of the hydro pump pintle arms. Rotate the eccentric adjustment collar until wheel rotation completely ceases at engine idle, then re-torque jam nuts to 25 ft-lbs.

Fuel Shut-Off Solenoid & Glow Plug Relay

If the engine cranks but will not fire, check the 12V fuel shutoff solenoid mounted to the injection pump rear. The pull-in coil draws approximately 25 amps through the ignition switch "Start" terminal, while the hold-in coil draws only 1 amp in the "Run" position. A failed hold-in coil causes the engine to die the instant the key returns from Start to Run.

Empirical Engineering & Statutory Verification Matrix

All tolerances and fluid formulas cross-checked against primary heavy machinery standards.

Engineering Parameter Authoritative Source Authority Body Factory Tolerance / Rule
Bobcat 743 Rated Operating Capacity SAE J818 Technical Specification Standard ↗ SAE International 1,300 lbs (590 kg)
Factory Service Manual Publication Melroe / Bobcat Workshop Service Manual Pub #6566109 (Section 10-01) Bobcat OEM Technical Service Division Verified Factory Documentation
Hydraulic Reservoir Service Capacity Bobcat 743 Lubrication Specification Table Bobcat Engineering Division 8.0 US Gallons (ISO VG 46 / SAE 10W-30 Motor Oil with ZDDP)
Kubota V1702 4-Cyl Diesel Engine Output Engine Manufacturer Service & Workshop Data OEM Powertrain Engineering 36 Gross HP (8.5 qts 15W-40 Heavy Duty Diesel (API CK-4))

Frequently Asked Technical Questions

Authoritative mechanical and operational answers verified against OEM shop manuals.

What is the rated operating capacity (ROC) of the Bobcat 743?

Under SAE J818 standards (50% of tipping load for wheeled loaders or 35% for tracked loaders), the Bobcat 743 has a Rated Operating Capacity of 1,300 lbs (590 kg). The static tipping load is 2,600 lbs (1,179 kg). Always operate within rated parameters to prevent rollover hazards.

What hydraulic fluid and reservoir capacity does the Bobcat 743 use?

The Bobcat 743 hydraulic reservoir requires 8.0 US gallons (30.3 Liters) of ISO VG 46 / SAE 10W-30 Motor Oil with ZDDP. The complete system capacity with cylinders and coolers holds 10.5 US gallons.

What engine powers the Bobcat 743 and what are the service intervals?

The Bobcat 743 is powered by a Kubota V1702 4-Cyl Diesel diesel producing 36 gross horsepower. The crankcase requires 8.5 quarts (8.0 Liters) of 15W-40 Heavy Duty Diesel (API CK-4). Oil changes are recommended every 100 to 250 operating hours based on duty cycle.

Where is the serial number located on the Bobcat 743?

Stamped on upright cab support plate behind operator right shoulder and stamped on lower left frame above left drive wheel.

What Wix filters fit the Bobcat 743?

Primary cross-references for the Bobcat 743 are: Engine Oil: Wix 51064 / Donaldson P550086; Hydraulic: Wix 51567 / Donaldson P550388; Fuel: Wix 33397 / Donaldson P550385; Outer Air: Wix 42222 / Donaldson P181050. Always verify thread pitch and seal diameter prior to spin-on installation.