Over heating

[William jackson]

I have a 2003 seadoo challenger with a 240 mercrusier when I take out cranks up idle out and soon as I take off goes in lymp mode due to overheating. Pulled power head and put all new gaskets but after assembling still over heats. I hooked up on hose and removed thermostat housings and no water flow coming out.

 

[Cobra Jet Steering LLC]

Something is obstructing the water jackets, did it sit for a long time?? maybe something built a nest inside of it.

 

[David Martin]

Look at the water pick up ports maybe some debris is blocking the intake.

 

[TeenGee]

This might be a dumb question.
Does your engine have a water pump?

 

[William jackson]

Something is obstructing the water jackets, did it sit for a long time?? maybe something built a nest inside of it.

Yes inside storage

 

[William jackson]

We blew air threw every port no blockage but when hook to water hose no water coming up threw right or left side of thermostat housing when overheating alarm goes off water just starts to dribble out right side

 

[William jackson]

Look at the water pick up ports maybe some debris is blocking the intake.

240 mec EFI jet drive all water comes threw jet pump

 

[William jackson]

This might be a dumb question.
Does your engine have a water pump?

No sir jet drive

 

[Cobra Jet Steering LLC]

you may have a stuck thermostat

 

[TeenGee]

I agree with CJS.
If you can remove your thermostat you can put it in a pot of boiling water. Automotive thermostats' control temperature is typically stamped somewhere on the thermostat.
If the thermostat opens at the correct temperature, check the instrumentation on your engine. The temperature sender could be faulty. The engine could be operating normally. The computer just thinks it's overheating.

 

[William jackson]

I agree with CJS.
If you can remove your thermostat you can put it in a pot of boiling water. Automotive thermostats' control temperature is typically stamped somewhere on the thermostat.
If the thermostat opens at the correct temperature, check the instrumentation on your engine. The temperature sender could be faulty. The engine could be operating normally. The computer just thinks it's overheating.

It don't have a thermostat the water constantly flows threw the system off the jet pump it's just a empty housing

 

[William jackson]

I am just totally confused we even pulled power head and can blow air threw all ports

 

[TeenGee]

Air flows much easier than water.
Can you get good water flow through the passages?

 

[William jackson]

Yes far as I can tell

 

[Cobra Jet Steering LLC]

I believe it should have a thermostat on the top of each head so your boat should have 2 of those it has an outboard power head and those had thermostats I would take a reading with a non contact thermometer of each head when it says it is overheating and see what the temperature really is with no thermostat it would run cold all the time.. if someone removed them your engine will run lousy and eat more fuel and I would also be looking at the temperature sensors .

 

[Cobra Jet Steering LLC]

Mercury 200-250 Hp Thermostat 130°F Replaces 8M0057307, 885599003 2 Pack

 

[William jackson]

The housing on both sides are empty no water coming out with housing cover removed off either side when I crank it which would make me feel like it's clogged but I can blow air threw both sides

 

[Cobra Jet Steering LLC]

Going to need to investigate the path from the jet pump to the engine block

 

[William jackson]

Thanks we did after pulling power head and got flow threw lines that I can see only thing we have not pulled is jet pump

 

[Cobra Jet Steering LLC]

that is a likely suspect for blockage