2006 90 hp 2 stroke alarm issue

[b.gandy3]

Hi guys. I'm having an issue with what I believe to be the over heat alarm. As soon as I turn the key on, without even trying to turn the motor over, the alarm starts going off. The motor obviously isn't overheating because it's not even on. Any suggestions on troubleshooting this issue?

Thanks.

[pstephens46]

Could it be a low oil warning? First priority is to figure out the warning. 2 stroke guys will show up shortly. Is your gauge indicating overheat?

[b.gandy3]

Multifunction gauges are shot so unfortunately can't refer to them. It's just a long continuous alarm sound. I don't know if it's supposed to be a different sound for oil vs overheat. It's never actually gone off under operation. The oil reservoir is full though.

[boscoe99]

The alarm is the same for over temperature as for low oil quantity.

If you suspect that it is a false over temperature alarm why not start with unplugging the over temperature sensor just to see what happens?

Do you have any 12 volt LED's laying around? You can use one, or a multi-meter, to see is the over temperature ground or the low oil quantity ground to the the tachometer, is being activated. If neither then it could be a low voltage issue causing the alarm to be set.

[b.gandy3]

Ok disconnected both the pink and black wire to the over heat sensor and the alarm still went off when I turned the key on. So I guess it's maybe related to the low oil sensor instead? I'm not sure where this sensor is located....

[walleye1]

If you have a oil injection system on that engine, the sensor is in thec top of the tank.

[b.gandy3]

Ok found the pink wire to the oil tank and disconnected it. Now when I turn the key on there is no alarm, so it definitely has to do with the low oil alarm. So at this point is it just replace the sensor on the oil tank or is there something else I need to check before going straight to that?

[zenoahphobic]

Ok found the pink wire to the oil tank and disconnected it. Now when I turn the key on there is no alarm, so it definitely has to do with the low oil alarm. So at this point is it just replace the sensor on the oil tank or is there something else I need to check before going straight to that?

Maybe the float ring is stuck down. When was the oil tank and inerds cleaned. 10 years of sludge might be on the bottom.
Careful in pulling this apart as often these will leak after putting them back together.

[boscoe99]

I would inspect the oil tank sensor. It contains two switches. One closes when the float is up and one closes when the float is down. First, as zeno notes, make sure that the float is in good condition and can move up and down freely in the oil.

Be careful when removing the sensor so as not to damage the seal that mates the sensor to the tank. There is also a seal that should be attached to the nipple of the sensor assembly. If not, fish it out of the tank. Note the orientation of the sensor strainer so that it can be reinstalled properly.

There is a procedure in the service manual for testing the sensor assembly on the bench. Do you need it?

[99yam40]

Before pulling it make sure you drain it completely and keep track of the foam seal and replace it when going back together.

There could be wiring problems also, so follow testing procedures in service manual.
no need to buy parts if they and not needed.

some motors have water in fuel and/or low voltage alarms also, so make sure what is causing this before buying parts

[b.gandy3]

Thanks guys. I'm going to run the boat tomorrow and use up some of the oil (I just filled it up). After the holidays I'll drain it and clean it out. Boscoe99 thanks for the offer on the bench testing procedure. If I get to that point I will definitely take you up on it. I appreciate the feedback fellas. I'll let you know what I find. Merry Christmas everybody!

[Glbarnes59@gmail.coM]

I have the same problem with my 1988 Yamaha 90 2 stroke when the key is turned on. I do not see a pink wire on the oil injector. There is a green and a green with pink Strip.

[ausnoelm]

Probably best to start a new thread rather than revive a years old one.