Kubota VS Mitsubishi Engines Comparison
Engine Valve Timing Mechanism
Kubota
Internally geared camshaft. Lubricated and protected from dirt and designed for the life of the engine.
VS.
Mistubishi
External timing belt. Exposed to dirty application conditions that can compromise belt life. Periodic replacement is required or there is a risk of catastrophic failure.
Kubota Advantage: Higher reliability and uptime. Reduced maintenance. No risk of catastrophic damage to valves due to timing belt failure. Designed to run reliably in tough industrial applications.
Potential for Pistons to Contact Valves
Kubota
Due to internal lubricated camshaft gears have minimal risk of valve train timing failure.
VS.
Mistubishi
If timing belt slips or breaks, extensive damage to the valves, cylinder head, pistons, crankshaft, and bearings may occur, resulting in expensive repairs.
Kubota Advantage: Virtually no risk of unplanned and expensive engine down time and repair due to timing issues.
Engine Head and Block Material
Kubota
Cast iron block and head with comparable thermal expansion rates reducing stress on head gaskets and cylinder head bolts.
VS.
Mistubishi
Cast iron block with aluminum cylinder head have differing thermal expansion rates, placing greater stress on the head gasket.
Kubota Advantage: A Kubota design cast iron cylinder head mated to the cast iron cylinder block is better suited to industrial applications for long-term durability. Whereas typical automotive-based engine designs are optimized for higher maximum power output, reduced weight, and minimal production cost (aluminum head/cast iron block). Kubota’s use of common materials between the cylinder head and block reduces stresses in the gasketed joints resulting in long-life. This minimizes the likelihood of random head gasket failures and associated downtime in high hour usage applications.
Crankshaft Bearings and Cylinder Block
Kubota
High capacity crankshaft bearings and cylinder block designed for diesel engine loads for long life.
VS.
Mistubishi
Crankshaft bearings and block optimized for lighter duty automotive usage of gasoline.
Kubota Advantage: Kubota main bearings are more heavy duty in design since they are based on the diesel platform; this provides greater reliability and longer life. More rigid engine structure on engine block (since borrowed from diesel) results in less radiated noise and vibration.
Parts and Service Availability
Kubota
World renowned for their reliability and for their parts and service network when needed.
VS.
Mistubishi
Limited support network, but does not carry the same reliability nor service access reputation.
Kubota Advantage: Well established quality reputation and service network to stand behind their products.