150TXRC overheat light flashing

[FlaTide2018]

Hi. My 150 TXRC is sending a signal that my engine is over heating and my RPMs go to 0, then 3 seconds later, it goes off and back up to whatever speed I was going. Just happened last Sunday and never had an issue with this before. No rhyme or reason, idle, slow, fast. Engine is clearly not hot, I can put my hand on it. Temp sensor is going bad?

[boscoe99]

If the motor is operating normally and the problem is just with the tachometer and the warning system then I suspect you have a low voltage issue.

I don't think a two stroke 150TXRC has a temperature sensor. Only two temperature switches.

[99yam40]

Hi. My 150 TXRC is sending a signal that my engine is over heating and my RPMs go to 0, then 3 seconds later, it goes off and back up to whatever speed I was going. Just happened last Sunday and never had an issue with this before. No rhyme or reason, idle, slow, fast. Engine is clearly not hot, I can put my hand on it. Temp sensor is going bad?

is it just the tach reading that goes to 0,
not the motor itself?
and when you say back to speed are you talking about just a RPM reading and not real speed of boat?

[FlaTide2018]

Tach goes to 0, engine still running, but kind of like in neutral. When the light goes off, tach goes back to 2k and the engine engages again and we start moving again. There is no pattern, just that sequence of events. Like an overridde if it thinks its too hot, which it is no where close to.
I took the cowling off today just to look around and dont see anything burned out or charred. looks normal.

[ausnoelm]

Still a very vague description of the fault, the "engine engages again" kind of indicates it's running, but not driving the prop?

[boscoe99]

I'm lost. No ideas.

[99yam40]

Still a very vague description of the fault, the "engine engages again" kind of indicates it's running, but not driving the prop?

agreed, neutral is way different than going into RPM reduction

[walleye1]

Tach goes to 0, engine still running, but kind of like in neutral. When the light goes off, tach goes back to 2k and the engine engages again and we start moving again. There is no pattern, just that sequence of events. Like an overridde if it thinks its too hot, which it is no where close to.
I took the cowling off today just to look around and dont see anything burned out or charred. looks normal.

What you are typing makes no sense. Try to make sense PLEASE.

[FlaTide2018]

I apologize. Let me start over.
Running my boat at about 2k RPM to 3k RPM. Tach will suddenly go to zero RPMs, overheat light turns on, engine is still running, but prop must stop spinning because we slow down. Lasts about 3-4 seconds, then the light turns off, engine revs back up and returns to 2k plus RPMs and we start moving again. I am not touching anything when this happens.
I tested it a few times by immediately shifting into neutral when the light turns on and the RPMs go down to zero. I would wait a few seconds, put it back in gear and start going again. Then the process starts over.
I've never had an issue like this before, or any over heating issues ever. I get it serviced yearly.

Hope that helps. Thanks.

[walleye1]

I think you have a voltage issue, either battery, battery cables, or connections on battery or on engine.

[boscoe99]

Sounds like the motor is going into RPM reduction mode due to low voltage. If indeed the motor is not getting hot.

[99yam40]

Can someone tell what RPM that motor is restricted to when high temp alarm kicks in?
thought most would be limited to 2K,so if running at 2 K or lower and over heat hit you would not feel any difference
anyway it should not be like the prop stops turning

[rodbolt17]

does the audible work?
if rpm reduction is generated it will bring the engine back to 2500 or so.
if below it cannot limit it.
with the limited info my money is on a voltage issue.
but do test the audible.