Temp sender 2008 343

[Cooperline]

Sorry guys if this has been posted before and hopefully simple but just cant find.
I have a poor temp reading on analogue dash gauge. Very low but moves just a little at end of pass as temp rises in engine. Its sounds like there are 2 senders in this model??
2008, 343 excal in 196 ( Not gateway version). I can easily see the two wire sender near the thermostat but from reading this is just for ECM?? Apparently single wire sensor for dash gauge somewhere on block?? Can not find it. Do some of these engines just use the one sensor and some how the two wire sensor feeds the dash gauge also?? Obviously was working recently and then went low. Sure the engine temp is fine. Maybe its the dash gauge?? How can i fault find?? Thank you.

[NautiqueJeff]

In this case, I would look at the thermostat first. When they fail, they typically fail open, causing the engine to never really warm up. If you see the gauge moving at the end of a hard run, I bet the gauge is fine.

https://nautiqueparts.com/thermostat...p026002/?aff=2

[JayG80]

NautiqueParts.com no longer offers the kit referenced above. It has been replaced by https://nautiqueparts.com/thermostat...p026002/?aff=2

If anyone knows, it would be nice to have an answer to the original question:
"I can easily see the two wire sender near the thermostat but from reading this is just for ECM?? Apparently single wire sensor for dash gauge somewhere on block?? Can not find it. Do some of these engines just use the one sensor and some how the two wire sensor feeds the dash gauge also?? Obviously was working recently and then went low. Sure the engine temp is fine. Maybe its the dash gauge?? How can i fault find?? "

[teamseal]

If your engine serial number falls between 470001 and 474440 you have this sending unit. If your boat is an analog gauge set up, it is relying on a manufactured signal from the ECM . if this unit fails or becomes out of range it will set a code. part number:R020019

[JayG80]

Thanks for the recommendation Jeff, I already ordered a new thermostat.

Thanks for the explanation Jody, my engine falls in that range. I hope the new thermostat fixes the analog gauge issue, if not I'll hook up my Diacom and look for a code.

[NautiqueJeff]

Definitely good info from Jody! Thanks for that info.

[Cooperline]

Thanks guys, Gives me something to go on.