Mariner 30hp Continuous Alarm

[TSoko]

I have a 1997 30hp Mariner with oil injection. It's used daily on a chase boat for the local high school crew team. As of yesterday, the continuous alarm sounds as soon as the ignition key is turned on, even with a cold engine. I've tried disconnecting the tan/lt blue temp sender wire, but the alarm continues. Oil reservoir (on the engine) is full. Engine appears to run perfectly. The wiring diagram in the Seloc Manual shows both oil and temp alarm wires going into the TPM Module (timing and protection module). Should I assume the Module is bad? ($$$$$$$) Thanks in advance.

 

[ozziebob]

Re: Mariner 30hp Continuous Alarm

Have you disconneted the low oil sensor at the bottom of the oil resiviour bottle??? This sensor could be your likely cause.

 

[andy6374]

Re: Mariner 30hp Continuous Alarm

A continuous beep is the overheat sensor NOT the low oil sensor.

Sounds like the overheat sensor is grounding out to the block. Trace it from the cylinder head back to the warning alarm while checking for wire chaffing.

 

[TSoko]

Re: Mariner 30hp Continuous Alarm

Ozziebob,
That seems to be the problem. When I disconnected the two blue leads from the bottom of the oil reservoir, the beeping stopped. I guess Mariner and Mercury alarms are different? Everything I read on this forum said that a continuous alarm was the temp, but on this Mariner it is the oil level. I'm guessing the oil level float switch is bad, which should be easier/cheaper to fix than the TPM module. Andy, looking for a grounded temp lead was one of the first things I did, but everything looks clean and neat. Thanks for your help.

 

[ozziebob]

Re: Mariner 30hp Continuous Alarm

Tsoko, Andy doesn't know it all like he thinks. You will probably find the problem is the magnet has broken of the float and is sitting in the bottom of the resiviour tank. The problem is not the switch as it is not being activated by the magnet. You can drain the tank and try to remove the speedy clip and repair the float but if you are not successful you will need a new tank not the switch. Mercury and mariner are the same but on some engines they have a module like you talked about in the selocs manual but i guessed yours was the one that both temp and oil both activate the buzzer direct.

 

[andy6374]

Re: Mariner 30hp Continuous Alarm

Tsoko, Andy doesn't know it all like he thinks.

Ozzie I don't think I know it all, but by the sound of it you must.

Back to his problem though:
Never, ever seen a beep beep beep beep alarm that is overheat and a beeeeeeeeeeeeep alarm that is oil. Why would Mercury change it for his engine. My initial guess is that it was coincidence that long continuous beep stopped when he pulled the wires from the oil resivoir, some wires are swapped and/or loose/corroded, or his warning module is acting up.

And 100% of the times when I've seen a continuous overheat alarm when the key is turned to the "ON" position (but not running) it has been the overheat switch grounding out.

Don't know what to tell ya. Can only tell the guy how the system is designed and intented to work.

 

[ozziebob]

Re: Mariner 30hp Continuous Alarm

Andy I only said what I said tounge in cheek. On these engines they didn't use an alarm module they electricaly tied the overheat and the low oil warning reed switch together to activated the warning buzzer. This is what I do for a living so I guess I am paid to know.

 

[andy6374]

Re: Mariner 30hp Continuous Alarm

bob-
Really. Then that's kinda of a bad, inconsistent design by mercury. Nothing like beeeeeeeeeeeeeep being overheat on one engine and low oil on another (not to mention that OMCs use the same warning beeps, ie continuous for overheat and intermitent beep for low oil.)

Good to know. 8)

 

[phatmanmike]

Re: Mariner 30hp Continuous Alarm

assume its a bad sensor. thats what my dealer told me on my 1995 40hp. he said a lot from that era went bad and did just that. disconnect it, i did. but i also have a water pressure guage to tell me whats up. do you?

 

[GGrant]

Re: Mariner 30hp Continuous Alarm

assume its a bad sensor. thats what my dealer told me on my 1995 40hp. he said a lot from that era went bad and did just that. disconnect it, i did. but i also have a water pressure guage to tell me whats up. do you?

 

[GGrant]

Re: Mariner 30hp Continuous Alarm

I have a 1990 40 hp mariner with the same problem. My manual says it's a faulty overheat sensor but went through the testing and that wasn't it. Have been searching for someone with the same problem and may have found the answer. When I take the sensor from the oil tank it stops the beep. Put it back in and it starts again. Manual doesn't say anything about a magnet in the tank that could be the problem.. Have been afraid to use it with the chance of overheating so was going to premix until I can verify this is the problem. Hope this helps. Thanks