95 Johnson 130 overheat alarm

I have a 95 130 looper that will overheat after 3-4 mins at 5000 rpm. I used a I/R thermometer to determine its on the starboard side. This has been going on for about a year and Im tired of chasing my tail. Heres what I have done so far. New pump and impeller, new thermostats, new heat sensor (starboard). Had the pump assy inspected to look for bad gaskets/seal, flip-flopped the heads to rule out a blockage, problem stayed on same side. Any help would be greatly appreciated.

Re: 95 Johnson 130 overheat alarm

i have a 85 120 looper does your motor have the valve that is conected behind the throtle linkage or not the valve has to do with the water discharge

Re: 95 Johnson 130 overheat alarm

does the engine overheat with the stats out. hmmmn
also hass the pwrhd ever been removed hmmmmn
what about the watertube, is it a tube or a cheese grater hmmmmn
what are you reading as far as temp. i had a 130 that did the same thing but only ran about 8degrees hotter on the strbd side
post some info on what i asked

Re: 95 Johnson 130 overheat alarm

hey also do you have the split line relief gearcase or the non split line, because the waterpump housing is different , one has a hole in it designed to relieve air from the waterpump in case the pump get air bound hmmmmmn

Re: 95 Johnson 130 overheat alarm

What temp readings are you getting?? You didn't say.
Is your motor going into the SLOW mode?

Re: 95 Johnson 130 overheat alarm

Temp reading would be nice to know,since this has been going on for a year.(and it still runs)

Starboard head will always run warmer,nature of the beast.But 163 degrees is overheat.

DHP

Re: 95 Johnson 130 overheat alarm

And if it isn't going into SLOW then it's probably the low fuel pressure warning.

Re: 95 Johnson 130 overheat alarm

Thanks to all that have posted, I am learning as I go but will try to give as much info as I know.

I have yet to pull the thermostats out and run it, I could try that later today if its advisable, I am not the original owner of this boat but it does not appear obvious to me that the power head has been removed before, THe motor IS going into SLOW mode after it overheats, my understanding is that this motor does not have a fuel restriction alarm. The temps I am reading off the cylinder after overheating are around 185-195. AS far as the split line relief gearcase, Im not sure, I will try to find out. I am taking the boat out with a local mechanic today, he has had the boat for a day or two and says he cant get it to overheat in the shop. he also says compression is fine. Looks like I will be giving away some more $$ for labor and no results. Thanks in advance for everyones help. I will post what if anything we find out today on the water.

Re: 95 Johnson 130 overheat alarm

Try flushing your motor in a barrel with some SaltAway (I think its called) or a strong mixture of vinegar water.
Run the motor until it reaches operating temp then shut it down and let cool. Repeat this as often as you can for about 2 days and then see if she still overheats.

Re: 95 Johnson 130 overheat alarm

Thanks Walker, I'll try that this weekend

Re: 95 Johnson 130 overheat alarm

deadinwater....keep us updated if ya fix it...my 94 140 is having the exact problems..

Re: 95 Johnson 130 overheat alarm

Went out on Friday with the mechanic and got the alarm to go off, he put his I/R thermo on it and said it was not getting hot(it was around 145 at the thermostat housing), he then installed a new temp sensor to replace the new one I had just put in, no alarm after running about 10 miles @ 5500 rpm. I am cautiously optimistic. Could I have been sold the wrong sensor to begin with?