Water pump leak?

[PutMeOnTheWater]

I’m sitting here scraping old gasket off to replace this thermostat and realized it didn’t even have a thermostat in there. So it definitely wasn’t stuck closed!

 

[ESGWheel]

Oh wow! So going to need some history here. Is this a new to you boat, etc.? Since you have owned it have you been out and running around with no issue until you noticed this leak? Need to know all as there may be damage to the exhaust system components due to lack of sufficient water flow. My understanding is that the t-stat provides (even when fully open) enough flow restriction to divert the needed water to the exhaust. This is not good.

 

[PutMeOnTheWater]

Oh wow! So going to need some history here. Is this a new to you boat, etc.? Since you have owned it have you been out and running around with no issue until you noticed this leak? Need to know all as there may be damage to the exhaust system components due to lack of sufficient water flow. My understanding is that the t-stat provides (even when fully open) enough flow restriction to divert the needed water to the exhaust. This is not good.

New to me, yes. I’ve taken it out 3-4 times. I ran about 3/4 of a tank of gas through it since I got it. I didn’t notice any temp issues before (although I could have missed it). One thing of note is that one of the exhaust (manifolds?) has JB weld on it and I did notice it leaking once around the hose clamp in the picture. I tightened it up and it stopped leaking.

 

[PutMeOnTheWater]

This is what it the flow looked like when I was running it the other night, after I changed the raw water pump.

 

[PutMeOnTheWater]

I hooked the garden hose up to each hose that runs to the exhaust and water flowed out of the back the boat on both.

 

[ESGWheel]

My understanding of how these water systems work on marine engines translates into:

• The temp gauge would not register an overheat (more likely under normal) but your exhaust system would be cooking with no t-stat installed.
• I would suspect the JB weld on the exhaust pipe is due to the prior owner mismanaging an overheating situation and thus cracked that pipe. I’ll bet those rubber connectors are new as the old ones may have melted.
• A though inspection to determine the health of this motor as well as the original root cause that motivated the prior owner to pull out the t-stat is needed.

I am out of my depth with this one in terms of what running a motor without the t-stat installed would do to a motor. Need help.

@Scott Danforth can you please provide some guidance / suggestions?. Thanks.