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just can't find what is wrong

O

old school 440

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i've got a new 1975 440 from first mate a week ago and placed it in my boat few days ago however it has got steam coming from the water out on the lake ,i have done everything i could no luck finding why or how.???
it also runs hot with in 3 to 4 min.. of running why is this i have pulled my 3" hoses off the muffers and i have got a good flow of water coming down the hoses? what could this be
?
this set up has got two pumps one is raw water from the lake to the heat exchanger.. and one is the pump that runs the coolant in the engine back to the heat exchanger.now i have checked both pumps and they are running great flow when i pulled hoses off of them while the engine was running.
WHY IS THIS 440 GETTING HOT SO FAST?? and steaming out the back
 
i also have done new thermosat and sending unit, and all that i could do by using the other 440 in the boat that runs great .i have traced all hoses and they are looking the same as the other engine hose by hose !!the other 440 in ethe boat runs at 160 temp.. and takes a while to get up to that and that one is great ,,
but this new one gets up to 190 temp with in 3 to 4 min.. of starting it up . please let there be someone on here that knows this set up and can help i have got all new i mean everything was placed on this new motor NEW from this marine engine .it does have the old SEN-DURE HEAT EXCHANGER on it however looks to be moving the water in it great?
here are some of my ideas but ??

maybe heat exchanger? dirty
maybe bad hose somewhere
maybe a riser or manifold is bad

i did run dish soap in the pump and i'm here to tell u it worked out the back of the boat.
 
Look for an air leak before the raw water pump. Even a tiny air leak will raise hell with cooling.

Also, is the motor timed right? Running with retarded timing heats 'em up fast.

Jeff
 
se i think you may be on the rite track i'm not sure on the timing but it starts rite up and runs nice does not back fire at all or miss but the timing could very well be off ? and where do i look for this air intake leak ?
 
i never knew that a air leak would do this but i could have one i guess i should look at the water hose coming in from the lake that is going to the raw water pump?
 
Might be an idea to go with all new hoses from the water intake right to the pump, new clamps, everything. Jeff's right about the timing, to far retarded & it will run really hot, might be an air lock in the motor too..did you fill the block & prime the system before starting it up?
 
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