1991 Mariner 115 Alarm

[DSM3]

Alarm goes off when we turn key, without even cranking engine. We disconnected the two blue wires under the oil tank and alarm still goes off. Engine is taking oil, and the pisser stream works fine, so engine seems to be fine in terms of getting cooling. We can't get the boat to a mechanic in the next few days, and need to use boat for transport, so am wondering if safe to disconnect the alarm at the horn.
Thanks in advance.

 

[marty53]

Re: 1981 Mariner 115 Alarm

Re: 1981 Mariner 115 Alarm

bad temp sensor (if this motor has one) or bad oil warning module (the box the two blue wires go into). its risky to disconnect (people do it), get the new parts ASAP.

 

[jimmbo]

Re: 1981 Mariner 115 Alarm

Re: 1981 Mariner 115 Alarm

81 Mariner 115 were inline 6s which had neither temp alarms, nor oil injection.

must be a typo 1991 perhaps

 

[DSM3]

Re: 1981 Mariner 115 Alarm

Re: 1981 Mariner 115 Alarm

Jimbo - you know your engines - yes typo, the engine is a 1991. And here is a report update - after consulting with a few knowledgable folks in the the harbor, out of necessity we disconnected the helm alarm. The reasoning was that the engine was consuming oil, since we had been adding engine oil for two weeks after disconnecting oil sensor alarm, and the cooling system was working, since the pisser stream was going strong, and since alarm was sounding without the engine even being turned on - the diagnosis is that there is a short or fault in the electrical system, that is causing the alarm to go off, with both the oil injection and the cooling systems working properly. So - anybody have any suggestions as to where to start with figuring out what is wrong or what might be failing with the electrical system?
Thanks in advance.

 

[marty53]

Re: 1991 Mariner 115 Alarm

there is a very simple procedure for isolating this. if you have a manual its in there. otherwise, breif summary: disconnect the oil sensor and temp sensor wires in turn, if one of them stops the beep replace that part and you are done. If they don't stop the beep, either your oil warning module is shot (just happened to me, failure rate is high) or you have a short to ground somewhere on one of the lines between the oil warning module and the warning horn up front.

 

[DSM3]

Re: 1991 Mariner 115 Alarm

Thanks for advice - will be at boat tomorrow and will try these out. I do have the Solux manual which I purchased at this site so will consult that as well.
Have a good and safe 4th everybody!