volvo 7.4 overheating at high temp

[tim10034]

i started my boat in a low tide to charge the battery and didnt pay attention but it was spitting out mud at the exhaust ....and started to run hot... it was running hot for quite time but after awhile of running in clean water the engine would stay at normal temp at 3000 rpm but would rise more and more with more rpms...i went home and decided to change the impeller and thermostat...but no luck it still overheats at rpms above 3000...but stays normal at 3000.. could something be clogged up i tried to drain the drain valves {cauks?} also one side of the exhaust is spitting out more water than the other on the through hull exhaust...thanks

 

[Bt Doctur]

Re: volvo 7.4 overheating at high temp

clogged manifolds, risers, thermostst housing, mud in the block."it was running hot for quite time but after awhile of running in clean water"<br />define quite a long time.

 

[tim10034]

Re: volvo 7.4 overheating at high temp

quite a long time.....mayabe 30 minutes of alternating speed to try keeping the engine from overheating...no mud in thermo housing...how do i clean manifolds riser and block????

 

[tim10034]

Re: volvo 7.4 overheating at high temp

is there any way to tell if risers or blocks manifolds are bad????how do i backwash this engine????thanks

 

[tim10034]

Re: volvo 7.4 overheating at high temp

well i solved the problem thought i would post in case someone else has the same...i back flushed the oil cooler by putting a garden hose to the hose going into the termo housing...make sure u take of the hoses on the water pump before u backwash