My DT30 3 cylinder two stroke engine overheats and I cannot find the problem.
When starting the engine, the water pump seems to be working as it discharge water at the piss hole and the water is warm. However, after about half a minute it stop and the motor overheats rapidly - usually after revving it above fast idle. The engine casing at the top cylinder shows some scars of overheating (spot lightly scarred and engine has a slight piston slap as a result at rpm over about 4000 but otherwise fine)
I did lowered the gearbox and checked the impeller and it seems fine - also pushed water up the water pipe in leg with a hose and the water exits the piss hole first, then work its way up and the out the thermostat opening (thermostat cover removed). When pouring water into the top at the thermostat hole with the hose, it flows out the pee hole and the tube that connects to water pump. IOW, no obvious obstruction I can find.
When the motor is started with thermostat casing removed, water does not makes it way out there...
What can be at fault? The engine was rebuilt after oil injection failure and the oil injection disconnect as a result by the previous owner. Currently it does not have a thermostat fitted - and I know the importance of the thermostat but if water does not reach it, how would it help
Any help or suggestions would be greatly be appreciated. Thanks
When starting the engine, the water pump seems to be working as it discharge water at the piss hole and the water is warm. However, after about half a minute it stop and the motor overheats rapidly - usually after revving it above fast idle. The engine casing at the top cylinder shows some scars of overheating (spot lightly scarred and engine has a slight piston slap as a result at rpm over about 4000 but otherwise fine)
I did lowered the gearbox and checked the impeller and it seems fine - also pushed water up the water pipe in leg with a hose and the water exits the piss hole first, then work its way up and the out the thermostat opening (thermostat cover removed). When pouring water into the top at the thermostat hole with the hose, it flows out the pee hole and the tube that connects to water pump. IOW, no obvious obstruction I can find.
When the motor is started with thermostat casing removed, water does not makes it way out there...
What can be at fault? The engine was rebuilt after oil injection failure and the oil injection disconnect as a result by the previous owner. Currently it does not have a thermostat fitted - and I know the importance of the thermostat but if water does not reach it, how would it help
Any help or suggestions would be greatly be appreciated. Thanks
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