1987 DT65 beeping problem

[ZackVon]

Can anyone help me please !
I get a red light saying it's overheating but the engine is cool and water is peeing smoothly out of the hole. I have replaced the impeller and oil flow sensor. This might be a water flow or heat sensor going bad ? Where is the water flow sensor located ? I think I know where the heat sensor's located, between block 1-3. Any help will be greatly appreciated.

Thanks !

Zack

[Solarman]

In '87 they didn't use water flow sensors on two strokes (to my knowledge), So check the wiring to your heat sensor and check your heat sensor per manual. Also make sure your thermostat is working. It is possible your sensor is good and the thermostat is stuck closed, your heads could get too hot (your sensor indicating a true problem). And yes, you could still have a good pee stream. You can use a laser temp gun ($25, at harbor freight) to check temps around the heads & cylinders.

Good luck. Post back what you find out.

[mphelle8vld]

The 87 didn't have a temp sensor, what's the serial# off of the transom clamp data plate?

[ZackVon]

I haven't check the thermostat to make sure it's not stuck. I have the water flow sensor out to check. I will check the thermostat and use the laser temp gun on it tomorrow.

Thanks !

[ZackVon]

Serial #'s
06502 705659

[mphelle8vld]

Interesting, the 87 was the J model with no temp sensor, the 88 (and apparently late 87s) were the K model with the sensor built into the cdi. If you pull the electrical cover and let me know the numbers printed in white on the front of the cdi, I can tell you for sure.

The sensor you removed from the head is a simple float switch that signals that the powerhead has filled with water to that point. Let me know if you have a 2 or 3 wire unit.

Photos would be nice, it's just shy of 30yrs old, the powerhead may have been changed at some point.

[ZackVon]

Sensor wire

I have three wires, Green/yellow, black, and purple/white

[mphelle8vld]

More interesting, the three wire was introduced around 90 but I suppose someone could have put that in and just used the float switch wire, the other wire is a built in temp sensor. Were all three wires connected to the harness?

Photos of the powerhead and numbers on the cdi will help identify the year.

[ZackVon]

Wires

There were only two wires plugged in, Green and I believe it was purple. I plugged all three in just to see, no difference.

[mphelle8vld]

My 90 schematic shows black as the common, violet w/white tracer as the temp sensor, and green w/yellow tracer as the float switch.

Is this a new problem or is the motor new to you?

[ZackVon]

This motor is kindoff new to me

I've had this motor for 1.5 year now and I've been running like a turtle while beeping. Now I have time to mess with it to take it fishing.

[mphelle8vld]

I'm sure you're in limp mode from the lights and beeping, guessing it won't run over 3k.

Let me know on the cdi and photos, hard to troubleshoot without a year, the electrics changed all the time.

Not sure when you changed the oil sensor, make sure to run premix until the air is bled from the pump and lines.

[ZackVon]

A little over a year now

I've had this motor little bit more than a year now, got it November of 2014. Ran it last summer this problem occur while I bought it. I have time this year to mess with it and want to resolve this so I can go fishing

[ZackVon]

Oil flow sensor

Yes I have changed the oil flow sensor already but haven't ran pre-mix gas, was just letting it run mix by itself

[ZackVon]

Beeping noise and light went away

Check thermostat and replaced water flow sensor got rid of the beeping noise.
Still not going pass 2k rpm. Any Ideas on what next besides unplugging the oil reset panel ?
Does anyone know what two wires to unplug ? I saw on another forum saying it was yellow/blue and black/?. I only have yellow/green.