Mariner 150 alarm help!

[xcrider]

Ok just bought a boat with a Mariner 150. Not sure on the year but i think its an 85 with oil injection.
My first question is that when i turn the key on i get a solid beeping sound from the dash until i push in the choke.. Is that normal?
Second question is sometimes when im idling or even up on plane i get a solid beeping that would indicate high temp. Even though ive got a good stream of water coming out of the motor. Sometimes this beep can be stopped with the key by pushing in on hte choke. Othertimes i have to put the boat in neutral or reverse or even stop the motor for a second and then restart. Sometimes it just goes away on its own. It seems really random.
Can anyone help me out here?

 

[galamb]

Sounds like you have a short at/near the keyswitch.

The alarm goes off when the circuit is grounded.

The alarm always has power. You should get a short beep on start-up (goes to ground when you turn to "start", ground is cut when it goes to "run") or if the temp sensor heats up into the "danger" range, the sensor "goes to ground" which completes the horn circuit - ditto the oil level sensor - if the oil gets to low, the sensor "closes" and completes the ground circuit = beeeep.

Since fiddling with the keyswitch can stop the horn, the problem most likely lies there. Might be nothing more than a loose wire or could be a keyswitch itself on the way out. You need to pull the keyswitch and take a look...

 

[xcrider]

Sounds like you have a short at/near the keyswitch.

The alarm goes off when the circuit is grounded.

The alarm always has power. You should get a short beep on start-up (goes to ground when you turn to "start", ground is cut when it goes to "run") or if the temp sensor heats up into the "danger" range, the sensor "goes to ground" which completes the horn circuit - ditto the oil level sensor - if the oil gets to low, the sensor "closes" and completes the ground circuit = beeeep.

Since fiddling with the keyswitch can stop the horn, the problem most likely lies there. Might be nothing more than a loose wire or could be a keyswitch itself on the way out. You need to pull the keyswitch and take a look...

i cant get it to beep at all now when i turn the switch on.. Im sure though that as soon as i get it on the water the beeping will come back.

Anyways, im going to go ahead and order a water pump kit and some new thermostats just to rule out over heating. And a manual as well. Anything else i should order while im at it?