Kubota Z602-E4 User Manual (English)

Questions and Answers:

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Emily WhiteAug 8, 2025
How to troubleshoot a Kubota Z602-E4 that is difficult to start?
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  Andrew WestAug 8, 2025
  If you are experiencing difficulty starting your Kubota Engine, several factors could be the cause. The fuel may be thick and not flowing properly; in this case, check the fuel tank and fuel filter, removing any water, dirt, or impurities, and clean the filter with kerosene if needed. Air or water mixed in the fuel system can also prevent proper fuel pump operation; check for loosened fuel line couplings or cap nuts, and loosen air vent screws to eliminate air in the fuel system. In cold weather, engine oil can become thick, causing slow cranking; change the grade of oil according to the temperature. Lastly, a discharged battery can prevent the engine from cranking; charge the battery, and in winter, remove the battery, charge it fully, keep it indoors, and install it at the time of use.
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Karen SaundersAug 14, 2025
Why does my Kubota Engine have insufficient output?
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  Mark CarpenterAug 14, 2025
  If your Kubota Engine has insufficient output, it may be due to a lack of fuel; check the fuel tank and refill if necessary, also check the fuel system for air or leaks. A bad nozzle can also cause this issue; if necessary, replace it with a new one. Additionally, moving parts may be overheated due to a shortage of lubrication oil or improper lubrication; check the engine oil level with the oil level gauge and inspect the lubricating oil system, replacing the oil filter cartridge every two oil changes.
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Danny SmithAug 27, 2025
Why does my Kubota Z602-E4 have bad exhaust color?
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  Michele WilliamsAug 27, 2025
  If the exhaust color from your Kubota Engine is bad, it might be due to extremely poor quality fuel. Select good quality fuel and use No. 2-D diesel fuel only. Another cause could be a bad nozzle, which may need replacement.
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Tanya GriffithSep 1, 2025
What to do if Kubota Z602-E4 stops suddenly?
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  Joel SchmidtSep 1, 2025
  If your Kubota Engine suddenly stops, check the fuel injection system, especially the fuel injection nozzle. Also, check the lubricating system, the function of the relieve valve, the pressure switch and the filter base gasket.

Kubota Z602-E4 Specifications

General

Engine Model	Z602-E4
Engine Type	Vertical, water-cooled, 4-cycle diesel
Number of Cylinders	2
Combustion system	Direct injection
Cooling System	Water-cooled
Starting System	Electric starter
Fuel	Diesel
Lubrication System	Forced lubrication
Type	Diesel Engine