Temperature alarm with good flow out pee hole?

[Force39]

Hi Gang, I have a 1996 120hp Force outboard. I was getting it ready for season and am getting the high temp alarm while running water via the ear muffs. Had good flow out pee hole. A couple years ago I changed the thermostat and it as been cooling fine since until now. I filled a large tub with water and about a half gallon of CLR to help clean deposits. First run after CLR it ran about 15 minutes and got alarm. Waited a half hour and started back up and it went for 8-10 minutes before alarm. Waited an hour, started got alarm in 5 minutes, again I was at idle speed. Does this motor have a poppet valve? Any help appreciated!

 

[The Force power]

Hi Gang, I have a 1996 120hp Force outboard. I was getting it ready for season and am getting the high temp alarm while running water via the ear muffs. Had good flow out pee hole. A couple years ago I changed the thermostat and it as been cooling fine since until now. I filled a large tub with water and about a half gallon of CLR to help clean deposits. First run after CLR it ran about 15 minutes and got alarm. Waited a half hour and started back up and it went for 8-10 minutes before alarm. Waited an hour, started got alarm in 5 minutes, again I was at idle speed. Does this motor have a poppet valve? Any help appreciated!

"HAD good flow" When was the last time you changed the impeller??
I would start there & Re-check the thermostat, running in salt water?
The engine block does not have a poppet-valve

 

[Force39]

Update: Started this morning, no flow out pee hole. Removed thermostat and ran still no flow. I run on a lake, no salt. Impeller changed 2-3 years ago, but it appears to be the problem like you said. Right? Thanks

 

[The Force power]

Update: Started this morning, no flow out pee hole. Removed thermostat and ran still no flow. I run on a lake, no salt. Impeller changed 2-3 years ago, but it appears to be the problem like you said. Right? Thanks

I would start with that. also stop running it without proper cooling!
When the lower-unit is off........force water up the P/U-tube (garden-hose) to see if water is flowing through the head passages.
Keep us posted

 

[Force39]

Will do, thanks!

 

[Force39]

Will do, thanks!

I bought a new water pump kit and replaced. Reinstalled lower unit. Started up and have strong discharge from pee hole! Old impeller looked good, but almost seemed stuck when removing it? Had to jump the battery to start boat, need new battery. I can hardly lift old battery, it is 27 series. I run nothing else electrical on the boat, can I use a 24 series battery?? Thanks for all the help!!

 

[The Force power]

I can hardly lift old battery, it is 27 series. I run nothing else electrical on the boat, can I use a 24 series battery?? Thanks for all the help!!

Yes, you can, but I would install a Rectifier/voltage-regulator so you don't "cook" the new battery