yamaha 115 alarm going off, not overheating

[pk911]

The problem is the overheating alarm goes off yet the motor is not overheating.The motor is 1998 c115. My buddy, to be on the safe side, changed waterpump, thermostats and sending units. Takes the boat out to see what happens and after 5 minutes, the alarm goes off. The pee hole is good and strong, water temp from the pee hole is normal. When he hears the alarm he lowers the rpm's and the alarm goes away. Runs the rpm's up again for another 3 minutes or so and alarm goes off. Not sure what the problem is. Any help on this is greatly appreciated.

 

[rodbolt]

Re: yamaha 115 alarm going off, not overheating

post the model number

 

[pk911]

Re: yamaha 115 alarm going off, not overheating

Originally posted by rodbolt:<br /> post the model number

the model number of the motor? I will have to call him to get it, thanks.<br />Pete

 

[pk911]

Re: yamaha 115 alarm going off, not overheating

Originally posted by pk911:<br />

Originally posted by rodbolt:<br /> post the model number

the model number of the motor? I will have to call him to get it, thanks.<br />Pete

Just got off the phone and the model number is c115 tlrw. I also saw something somewhere else that said it may be a loose battery connection? Thanks for any help.

 

[rodbolt]

Re: yamaha 115 alarm going off, not overheating

the W indicates its a 98, the manual only refers to motors up to 95 using the loose battery alarm but its a belief that the later models did as well.however my argument was on the C models it cannot as the C model CDI does not have a yellow key on power source nor does it have an oil control module so it cant set any alarms for low voltage.<br /> the jury was hung but swaying my way.<br /> we did have some issues with scale building up inside the block and under the cyl water covers and creating a hot spot, usually happens above 3800 RPM. as does a leaking head gasket.<br /> if after all the other cooling system maint is properly done and your still getting an overheat it may be time to pop the heads,<br /> when the alarm triggers does the engine go into an RPM reduction mode and light any indicators on the tach or speedo ?

 

[pk911]

Re: yamaha 115 alarm going off, not overheating

Originally posted by rodbolt:<br /> the W indicates its a 98, the manual only refers to motors up to 95 using the loose battery alarm but its a belief that the later models did as well.however my argument was on the C models it cannot as the C model CDI does not have a yellow key on power source nor does it have an oil control module so it cant set any alarms for low voltage.<br /> the jury was hung but swaying my way.<br /> we did have some issues with scale building up inside the block and under the cyl water covers and creating a hot spot, usually happens above 3800 RPM. as does a leaking head gasket.<br /> if after all the other cooling system maint is properly done and your still getting an overheat it may be time to pop the heads,<br /> when the alarm triggers does the engine go into an RPM reduction mode and light any indicators on the tach or speedo ?

Rod,as far as I know, the motor does not go into a rpm reduction. He just lowers the rpms and the alarm goes off. Would an overcharging the battery set the alarm to go off. The boat sat for like 3 months before I sold it to him but I never had any alarm go off the three years I ran the boat. It ran like a raped ape.I am going to ask him to take a reading on the batteries and see what he has. Not sure if he is running the batteries in "both", 1 or 2. I will find out. He may also post on here as I told him about the posting. Thanks again Rod.<br />Pete

 

[rodbolt]

Re: yamaha 115 alarm going off, not overheating

there again what part of the CDI on that motor has 12volts going to it?<br />if your CDI has a yellow key on 12V powerfeed it could very well monitor battery voltage, I dont think the C models did but I may be wrong.

 

[pk911]

Re: yamaha 115 alarm going off, not overheating

Originally posted by rodbolt:<br /> there again what part of the CDI on that motor has 12volts going to it?<br />if your CDI has a yellow key on 12V powerfeed it could very well monitor battery voltage, I dont think the C models did but I may be wrong.

Well here is the update on the issue. While looking at the batteries and checking for good connections, my friend found 2 ground wires barely hanging on by a thread. One ground was for the bait well, reconnected that and worked well. Reconnected the other ground wirem, much thicker, heat shrunk the connections and took it for a spin. Tada---no more buzzer at any rpm. Case solved. Thanks to all that have helped and hope this can help others in the future. <br />Pete

 

[rodbolt]

Re: yamaha 115 alarm going off, not overheating

not gonna argue I just cant seeit.<br /> the engine ground is a single cable.<br /> but the RPM reduction is simultaneous with the alarm horn, ya cant get one without the other.<br /> the CDI or ECU will set the alarm, however the C model CDI has no provision to monitor battery voltage.<br /> my personal 95 model C115tlrt would not set a low voltage or battery alarm and my buddies 115tlrv model will. but its not a C model.<br /> this question was brought up a week ago at the training facility and no one could answer it.<br /> thats why I asked about the RPM reduction, it should have gone into RPM reduction if it was a CDI triggered alarm.<br /> so like I say, something is funny. the C model cannot monitor battery voltage as it has no battery voltage inputs, the C model CDI only looks for overheat and any alarms set on the C model will drive it into RPM reduction if above 2000 RPM.

 

[pk911]

Re: yamaha 115 alarm going off, not overheating

Originally posted by rodbolt:<br /> not gonna argue I just cant seeit.<br /> the engine ground is a single cable.<br /> but the RPM reduction is simultaneous with the alarm horn, ya cant get one without the other.<br /> the CDI or ECU will set the alarm, however the C model CDI has no provision to monitor battery voltage.<br /> my personal 95 model C115tlrt would not set a low voltage or battery alarm and my buddies 115tlrv model will. but its not a C model.<br /> this question was brought up a week ago at the training facility and no one could answer it.<br /> thats why I asked about the RPM reduction, it should have gone into RPM reduction if it was a CDI triggered alarm.<br /> so like I say, something is funny. the C model cannot monitor battery voltage as it has no battery voltage inputs, the C model CDI only looks for overheat and any alarms set on the C model will drive it into RPM reduction if above 2000 RPM.

I can understand your not believing it but the proof is in the pudding, so they say. I reported it just like I was told and passed on the information. Maybe there is something else added that we do not know about that caused it. All I know is the alarm is not buzzing any longer, did not have a reduction in rpms, and once the ground wire was fixed, problem went away. I do not think it was the big ground wire to the battery, rather a smaller version. Would the buzzer have a ground wire? perhaps that was the wire that was re-attached. Nonetheless, he is happy and fishing and I feel better that it is not a motor issue. Thanks again Rod.

 

[rodbolt]

Re: yamaha 115 alarm going off, not overheating

nope, the only ground the keyswitch,buzzer and engine care about is the cable from the battery to the engine, all others at the battery are hull acessories.<br /> unless some one has jinky wired it someplace in the past.

 

[bayhawk14]

Re: yamaha 115 alarm going off, not overheating

I'm having the same issues with the same motor (98 Yamaha C115). I took it out today & it overheats at 4K RPM. If I backed it down to 3,500 I can run it all day. I've changed the impeller, both themo's & checked poppit (replaced spring). I did have to change the digital tach becasue part of the numbers were not lighting up. This is around the same time the engine started acting up. Could I also have a bad ground wire? Where would I look for it? Any help is greatly appreciated.

 

[blandes]

Re: yamaha 115 alarm going off, not overheating

Did you find a solution? Mine is doing the same thing. I am leaning towards checking the head gaskets and corrosion (it was ran in salt water).

Thanks,

Bob

 

[mibowman]

Re: yamaha 115 alarm going off, not overheating

I was having the same problem. i discoverd that a transducer was located on the transom directly in the center . Wheh the boat remained at higher rpm the water was being diverted away from the inlets thus causing the alarm to sound at higher rpm and not at the lower