The Bobcat 643 Skid Steer Loader is a versatile, mid-sized machine featuring a durable Kubota diesel engine and reliable hydrostatic transmission. Built in the late 1980s and early 1990s, the 643 was designed for serious work in agriculture, construction, and landscaping. With a 1,300 lb rated lift capacity and responsive control system, this model remains a go-to for operators who value simple maintenance, strong performance, and efficient fuel use.
Specifications & Features:
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Engine: Kubota V1702-B, 4-cylinder liquid-cooled diesel
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Engine Power: 32 hp @ 2,800 RPM
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Hydraulic Pressure: 2,000 psi
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Pump Flow: 11 GPM
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Rated Operating Capacity: 1,300 lbs
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Operating Weight: 4,480 lbs
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Lift Type: Radial lift
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Transmission: Hydrostatic drive, lever-controlled
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Travel Speed: 6.6 mph
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Tires: 10x16.5 standard
Common Maintenance Needs:
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Hydraulic cylinder seal kits – required for lift and tilt cylinder rebuilds – Shop Bobcat 643 Hydraulic Kits
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Kubota V1702 engine parts – air, oil, and fuel filters plus glow plugs – Find Kubota Engine Parts
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Drive belts and tensioners – vital for cooling system reliability
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Fuel system components – fuel lines and solenoids prone to wear with age
Common Issues & Quick Fixes:
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Hard starts in cold weather: Replace glow plugs or check preheat circuit
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Weak lift arms: Rebuild hydraulic cylinders or check for low fluid
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Hydraulic leaks: Common at hose fittings and cylinder seals
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Overheating: Flush radiator and inspect water pump or belt tension
Pro Tips:
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Always bleed the fuel system after filter changes to prevent hard starting
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Use a 50/50 mix of antifreeze and distilled water to protect the cooling system
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Check hydraulic fluid level every 10 hours of use for consistent performance
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Grease all pivot points frequently to avoid premature pin/bushing wear
Serial Number Location:
The serial number plate is typically found on the loader frame near the engine compartment or beneath the operator seat.
