1990 Yamaha 150 slow mode and alarm.

[papawoulfe]

My yamaha 150 runs perfect at mid range at below 30MPH. When I get to full speed at above 40 MPH the alarm comes on and the engine speed drops. If I turn the motor off and let it rest for a minute, I can start it back up and the motor runs fine. Got a water stream at the drain hole. I have made repairs to the wires to the auxilary tank pump. The auxilary tank pump motor is running when the ignition switch is turned on. The motor only has 650 hrs,

 

[rodbolt]

Re: 1990 Yamaha 150 slow mode and alarm.

your visual indicates on the tach will tell you if the alarm is overheat or low oil level in the engine tank. the remote tank is not monitored with any alarms other than a yellow visual on the tach.

 

[JUSTINTIME]

Re: 1990 Yamaha 150 slow mode and alarm.

if you need the dealers troubleshooting guide on the oil system shoot me an email

 

[angjackson29]

Re: 1990 Yamaha 150 slow mode and alarm.

I have a Yamaha 115 4 stoke with gas smell in oil. When idling it surges rpms a little. any clue where gas is coming from?

 

[JUSTINTIME]

Re: 1990 Yamaha 150 slow mode and alarm.

fuel pump

 

[angjackson29]

Re: 1990 Yamaha 150 slow mode and alarm.

after lots of free advise, someone suggested that it could be thermostat making it run too cool ie calling for more gas? could you elaborate about fuel pump?
thanks for your reply

 

[vmaxjay]

Re: 1990 Yamaha 150 slow mode and alarm.

Hmm...The only time mine has ever went off was when the oil pump quit working and one other time when I got some grass in the water pick ups... How many #'s of water pressure do you have at 30+ mph? Also... did you check your oil reservoir (the one on the engine) to check the oil level? It has to be withing those 2 lines or it will go off.

 

[JUSTINTIME]

Re: 1990 Yamaha 150 slow mode and alarm.

it be either t stat or fuel pump

 

[angjackson29]

Re: 1990 Yamaha 150 slow mode and alarm.

It was the t-stat stuck open,changed it and the oil and motor is running fine.