Obviously this is some sort of exhaust related issue, but was shocked to see that it melted a hole in the cover. Any ideas why the exhaust is this hot? Do I have a problem? What is the cause and repair needed? I know my water pump needs to be replaced, is it that the engine is running a littler hotter than it should due to work pump?
it would help if you gave some information on year, model, and make of the engine
Proline 201WA
Aloha 24ft pontoon (LooneyToon)
Old Town stern with 7.5 johnson
2013 Yamaha 20hp F20SMHA
I have one just like yours,did the overtemp light come on?How do you know that the water pump is bad?Did you overfill the oil?
To my knowledge the over temp light came on once a year or so ago when it was idling in pluff mud. I was casting for bait and didnt notice. No audible alarm. ( I bought the motor used). I think the pump impeller is bad because it doesn’t per very strong when idling or on earmuffs when flushing. I just noticed the melted cowling this weekend, so not exactly sure when it happened. I must have been recently maybe even my last trip because I’m pretty meticulous with my stuff and I fell I would have noticed right away. Lots of carbon build up under this cowling area (second pic) and there is some sort of secondary exhaust port adjacent to this melted spot. Just curious if others have seen this before or if it’s an indicator of a bigger problem.
Also I’ve nevet overfilled the oil. Just Changed it today in fact. I’ve dropped the lower unit to change the impeller today also. Waiting on parts.
What did the old impeller look like? Thrashed?
no, impeller was fully intact and appeared ok. Not pliable at all, very rigid. bottom plate has some scratching.
Parts arrived yesterday. Reassembled and tested. Very easy. Based on discharge of the pump now vs. before, it certainly needed to be replaced. After doing this for the first time, I realized that a manual would not be necessary for this particular job. Recommended interval for water pumps is 3 yrs I think, and this one was very likely 6 years old.