Starboard Engine Overheat Warning

[raptor319]

2016 Yamah 242 E-Series...38 hrs. Just bought and getting Starboard Engine Overheat Warning after 15 mins or so running. Water coming out both pee holes but Port temp is warm as expected and Starboard is cold. Should it be warm since it is dissipating/transferring heat from engine? Thermostat issue maybe/salt crystals?
When I did demo run on it with owner...same warning popped. So I took it to shop and they ran a scanner on it and a lake test and could not duplicate issue.
Thoughts?

 

[swatski]

2016 Yamah 242 E-Series...38 hrs. Just bought and getting Starboard Engine Overheat Warning after 15 mins or so running. Water coming out both pee holes but Port temp is warm as expected and Starboard is cold. Should it be warm since it is dissipating/transferring heat from engine? Thermostat issue maybe/salt crystals?
When I did demo run on it with owner...same warning popped. So I took it to shop and they ran a scanner on it and a lake test and could not duplicate issue.
Thoughts?

Water should be warm... Sounds like there may be a blockage in the intake lines, I don;t know enough to tell if a thermostat could be a culprit. But something is not right.
@buckbuck posted great instructional videos in the FAQ section, different engine model (MR-1 from yours (1.8) but very similar cooling system.

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[Scottintexas]

update your location in your profile so we know where you are at,

Where did the boat come from? fresh or salt water?

running for 15 minutes at wide open or were you in no wake?

Buck's video will be a good help for you, along with a YDS scanner and an infra-red thermometer,

You should have four pee holes, one indicating thermostat the other indicating pressure, be sure to trace them back to the engine incase someone hooked them to the hull backwards,

 

[raptor319]

Updated Profile...thx. Orlando FL area...
Have only been in salt so far. The newer 1.8L HO engines only have (1) pee hole per motor I believe not 2 per as with the older models

 

[zipper]

Updated Profile...thx. Orlando FL area...
Have only been in salt so far. The newer 1.8L HO engines only have (1) pee hole per motor I believe not 2 per as with the older models

You do have another set of cooling lines.



The pilot water outlets are visible on starboard side hull below rub rail. The thermostat cooling water outlets are on the transom plate I believe, but the diagram shows them mounted horizontally. @swatski or @Mainah with same engines/boat will know where they exit. Sounds like a stuck thermostat perhaps blocking water flow thru the engine. The water you are feeling is cooling water thru the oil cooler. If the thermostat is stuck closed, water will not circulate through the block/head causing the water within to overheat and send alarm. While the oil in the cooler may be warm and not exchange much heat.

 

[raptor319]

Ok thanks for the info...so should I bee looking for water exiting from pilot holes other than the 2 pee holes?

 

[spatty99]

You could snake some weed whacker line into the cooling water outlet if there happen to be any small obstructions nearby.

 

[raptor319]

I will try that...though I do not see any restriction with flow from the cooling ports. The only anomaly is warm water coming from port and cool water coming from starboard (engine giving me warning)

 

[swatski]

I will try that...though I do not see any restriction with flow from the cooling ports. The only anomaly is warm water coming from port and cool water coming from starboard (engine giving me warning)

There is only one intake inside the pumps. Let me grab the service manual.
Do you notice if the engine block or the exhaust manifold are hot-er by any chance?

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[raptor319]

a passenger did mention it seemed starboard engine side seemed hotter

 

[swatski]

I will try that...though I do not see any restriction with flow from the cooling ports. The only anomaly is warm water coming from port and cool water coming from starboard (engine giving me warning)

Assuming the boat is the 3-star (not CARB, California 4-star)

 

[swatski]

a passenger did mention it seemed starboard engine side seemed hotter

I remember @buckbuck had a weird obstruction in a factory cooling water hose or connector. It was a plastic extrusion defect that was partially blocking the line. Can't find it know, but it could be a similar issue, possibly?

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[spatty99]

@swatski That was a molded y tee, I believe the one that combines the flush and pump lines.

With this affecting only one engine, my thought is thermostat or line blockage somewhere on the overheating engine.

I just had a random overheat on single engine after extended high speed, and it resolved after the reverse maneuver, which I presume cleared some tiny junk in the cooling intake area.

 

[raptor319]

awesome info...thanks for the diagrams. So wondering if I should take it to shop with this data. I am a cybersec guy and not too mechanical. I can do oil changes etc lol. would love to fix on my own though

 

[raptor319]

what is the "reverse maneuver" mentioned above?

 

[swatski]

what is the "reverse maneuver" mentioned above?

https://jetboaters.net/faq/i-keep-g...ps-any-tips-to-help-aka-the-reverse-trick.66/

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[raptor319]

awesome...will try Saturday...Dont think I have anything stuck in grates or impeller shaft but maybe this will clear out any cooling system blockages??

 

[swatski]

awesome...will try Saturday...Dont think I have anything stuck in grates or impeller shaft but maybe this will clear out any cooling system blockages??

I am absolutely not an expert, but I would be doubtful the reverse maneuver would help, it is meant to help by pushing crap back out the intake grates.
If you have an easy access to a dealer or a good mechanic familiar with these boats it maybe the easiest path. If it is a stuck thermostat it could be a quick fix.
Keep us posted!

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[raptor319]

So finally got boat back from shop...turns out it WAS a corroded thermostat and some collapsed/crimped cooling system hoses leading to it. Cant wait to take out this weekend on Gulf of Mex.
Thanks for all the help and input

 

[raptor319]

So problem solved...no overheat this time! Also as an added bonus I found out the boat has 2 years left on the Yamaha extended warranty.