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Really weird issue need help. Engines overheating randomly Yamaha/Dealer says it’s not happening

Cobra Jet Steering LLC

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I have noticed that when running on the hose the stream is warm very quickly so it must be coming from the engine , if you do not have water coming out it does NOT mean that water is not present in the engine as the hose could be blocked . if the thermostat is not working you could have water and an overheat issue or if the water passages are filled with sand but that would be a consistent situation, you can also remove the thermostat and place it in a pan of water use a cooking thermometer to read the water temp while you heat it on the stove and watch what temp it opens at as well as the fact that it opens.
 

FLJetBoater

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I have noticed that when running on the hose the stream is warm very quickly so it must be coming from the engine , if you do not have water coming out it does NOT mean that water is not present in the engine as the hose could be blocked . if the thermostat is not working you could have water and an overheat issue or if the water passages are filled with sand but that would be a consistent situation, you can also remove the thermostat and place it in a pan of water use a cooking thermometer to read the water temp while you heat it on the stove and watch what temp it opens at as well as the fact that it opens.
Any videos on here of how to remove the thermostat or can you point me to the diagram where it’s located? Interestingly, I just ran the boat on the hose for 15 mins and no overheat. I did top up the oil as it was right at the low mark (cold). Wondering if that may have been playing a part. Do you know how much oil would be between low and full? I put in about 20oz and it’s about half way now.

Also noticed this morning the ground from my DVSR was completely broken off from the battery terminal. Just stripped it back a few inches crimped a new terminal connector on it.

arent boats fun :)
 

Cobra Jet Steering LLC

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well I had an oil filter split once and the alarm went off and it went in limp mode so I checked for weeds in the pump or a plastic bag but found nothing so I started it and it ran fine for about 3 or 4 minutes and it did it again so I stopped and still no weeds not sure if your helm tells you why the alarm was going off but my alarm did not indicate what was wrong so I checked and found oil everywhere . So perhaps it is the low oil that is the reason for the alarm like I said I am not familiar with your warning system. but I would be looking for the reason for the low oil, Also when I think back about the 2010 ski that had the bad heat sensor I remember that it started acting up after one of my sons ran the ski in weeds and kept riding until the alarm went off and he had to get in the water to free the weeds. I was not with him when he did it so I don't know how long he ran it in limp mode without proper water. I always warn people limp mode is NOT SAFE MODE it's shut it off and find the problem before you ruin something expensive mode.
 

FLJetBoater

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well I had an oil filter split once and the alarm went off and it went in limp mode so I checked for weeds in the pump or a plastic bag but found nothing so I started it and it ran fine for about 3 or 4 minutes and it did it again so I stopped and still no weeds not sure if your helm tells you why the alarm was going off but my alarm did not indicate what was wrong so I checked and found oil everywhere . So perhaps it is the low oil that is the reason for the alarm like I said I am not familiar with your warning system. but I would be looking for the reason for the low oil, Also when I think back about the 2010 ski that had the bad heat sensor I remember that it started acting up after one of my sons ran the ski in weeds and kept riding until the alarm went off and he had to get in the water to free the weeds. I was not with him when he did it so I don't know how long he ran it in limp mode without proper water. I always warn people limp mode is NOT SAFE MODE it's shut it off and find the problem before you ruin something expensive mode.
I changed the oil about a month ago now and put back in what I took out; it’s possible it was low before that. No oil visible anywhere in the engine compartment. Some water but perfectly clear not oily.

I have never used or seen limp mode, I’m not sure the 2014s have it. I just turned it off and idled back on 1 engine.

out this morning.....flushed for 15 mins on hose with salt away. Out into intracoastal 15 min run @ 30 mph and no alarms. Odd

I dunno....will the shop be able to do anything if it’s not showing symptoms anymore?
 

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They can test the sensors if it is a bad one it will do it intermittently. I run only salt water in the gulf of Mexico and I use car wash soap with liquid wax to rinse my engines it seems to work fine and leaves a slight film on the inside of the water jackets , plus I can see when the soap suds stop coming out I know the flush is complete. The way to know if it is overheating is to take readings after you run the engine so you know the base line and then when the alarm goes off take readings and compare the temperatures, places like the exhaust manifold and water box are good to check as well as the front and rear of the engine block.
 
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