overhaets at 4000rpm

[four m]

its a 1990 evinrude 60hp the mechanic before me put a impeller in and a new exhaust plate.run the boat all day at 3500rpms no buzzer.you go 4000 then buzzer goes off (yes steady beep).i put in a new impeller and thermastat.same problem,i tried gutting the stat and it ran too cool.it gets good flow thru thermastat hole. the only thing i can think of is i should have put in a complete water pump,the housing looked good so did the impeller.installed a temp but he got the boat up for winter

 

[jonesg]

Re: overhaets at 4000rpm

Thats probably fuel restriction(solid beep), not temp.
Pump is losing ability to deliver at higher rpm or a restriction ,
that could be a blocked tank vent too.

 

[kenmyfam]

Re: overhaets at 4000rpm

Could well be fuel related.

 

[James R]

Re: overhaets at 4000rpm

I recently started the break in on a 150 Fast Strike. Initially had a temp problem at over 3K rpm which we think was as a result of the wrong plugs. Changed the plugs and temp stabilized and the gun showed good temps.
brought the rpm up to 3.5K and the motor died and a continuous beep the same as the overtemp came on.
I was running on a 6 Gal tank and the small fittings apparently would not pass sufficient fuel. Switched to the on board tank and all is well.
Your situation may be fuel starvation, a restriction somewhere.

 

[four m]

Re: overhaets at 4000rpm

its got the right plugs the vro is disconnected the vro is pluged and wire disconnected .the only thing is the tan wire on the temp sensor

 

[four m]

Re: overhaets at 4000rpm

Thats probably fuel restriction(solid beep), not temp.
Pump is losing ability to deliver at higher rpm or a restriction ,
that could be a blocked tank vent too.

vro is pluged and disconnected has 12 gal ob tank on pontoon boat

 

[Willyclay]

Re: overhaets at 4000rpm

Have you checked the powerhead to see if it is really overheating? I had the same problem with an older Johnson V4 and installed a water temp gauge for verification. When the temps remained cool inspite of the overheat warning, I replaced the sensor and the overheat indication went away. Good luck!

 

[reeldutch]

Re: overhaets at 4000rpm

you got it to run cool with the tstat gutted?

it didnt overheat?

i think your spring (poppetvale) is not opening enough at high speed.

at low speed only the tstat controls the amount of waterflow at high speed the waterpressure overcomes the springtension and opens op so more water can flow out to cool of fasten.

check the condition of it .
i do believe they have different springs for different waterpump impellers. on that model.

i think you have it miss matched by accident.

 

[four m]

Re: overhaets at 4000rpm

Have you checked the powerhead to see if it is really overheating? I had the same problem with an older Johnson V4 and installed a water temp gauge for verification. When the temps remained cool inspite of the overheat warning, I replaced the sensor and the overheat indication went away. Good luck!

Yes its running hot and motor shakes let it sit for 15 min to cool keep momintay turn on ign horn will beep until cool.Start and run wont buzz below 3500 can for hours

 

[four m]

Re: overhaets at 4000rpm

Have you checked the powerhead to see if it is really overheating? I had the same problem with an older Johnson V4 and installed a water temp gauge for verification. When the temps remained cool inspite of the overheat warning, I replaced the sensor and the overheat indication went away. Good luck!

I installed temp gauge after he pulled it out for the winter we will se next year