what are the normal operating temps on rwc 4.3 omc

[dtime]

my 91 4.3 omc seem to run cool? running 120 even if i run it hard. not sure if it is a malfuntioning temp gauge or defective thermostat? the gauge does work i have personally seen it raise to 160 - 180 while on the muffs by limiting/ resticting the amount of water to the motor.

 

[Bt Doctur]

Re: what are the normal operating temps on rwc 4.3 omc

Might be time to replace the impeller if it was damaged by restricting the flow .
Try replacing the sender, verify temp with a laser before you test the gauge by shutting off the water flow again.

 

[Lou C]

Re: what are the normal operating temps on rwc 4.3 omc

They will run cool like that if there is piece of rust that keeps the thermo from closing all the way...I usually have to replace the thermostats on my RWC 4.3 every 2 seasons or so...sometimes if you run it fast enough to get the temp up to normal (160) then the rust will pass through and the thermo will start working normally again...if not replace it...it's held in the thermo housing by a black rubber ring that fits into a groove in the thermo housing..

 

[sdoomaha]

Re: what are the normal operating temps on rwc 4.3 omc

Can't speak for OMC for sure....but on my Merc...the temp sending unit sits in the thermo housing "outside" the thermostat. My thermo was stuck closed...but I never knew it because the water circulating around the block never made it out to the sending unit. I thought I was running cool...but the minor temp change I was seeing was from the thermostat housing conducting heat through the metal. Check your thermostat....it may be stuck open....or even worse...if like mine could be stuck closed and you wouldnt even know it.

Good Luck.

 

[dtime]

Re: what are the normal operating temps on rwc 4.3 omc

Pulled te thermostat out and checked it. found the unit stuck open. i replaced it and its runnig at normal ranges 140 - 160 f



thank you

PS i never shut of the water to the motor just reduced the gpm going to it