25hp 4 stroke Mercury no tell tale in lake

I just bought a 25hp Mercury and hooked it to the boat with the muffs. It ran fine, water shot out of the tell tale for 10min, motor was not hot. Put it in the lake and very little water came out the tell tale (just a dribble). Ran it for 20min the engine din not feel hot. The water temp gauge does not work. The guy I bought it from said it had a new water pump. ANY ideas on what to do? Thanks in advance

The first thing to do when you don't see a Tell Tale is to check the motor see if it's overheating. The best place is the exhaust plate (usually on the left side with Mercs). If you can't touch it with your hand without getting burned it's too hot. If cool--roughly 140 ' F--you can keep your hand on it for several seconds.

Jeff

PS: No serious boater should be without an infrared temp gun. Dirt cheap, you can 'shoot' the block and see exactly what's going on.

fastjeff said:

The first thing to do when you don't see a Tell Tale is to check the motor see if it's overheating. The best place is the exhaust plate (usually on the left side with Mercs). If you can't touch it with your hand without getting burned it's too hot. If cool--roughly 140 ' F--you can keep your hand on it for several seconds.

Jeff

PS: No serious boater should be without an infrared temp gun. Dirt cheap, you can 'shoot' the block and see exactly what's going on.

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thanks, I will go out on the lake today and feel the engine for the heat level. If its not too "hot" (burning ~above 140) then it must be getting cooling water? The tell tale is nice to see, but I wonder if this is just the way the motor is and live with it..... I bought this motor for $1200 and its over 20yrs old. I expected it to have issues but nothing to serious that would destroy itself. If the impeller is new, then what would be the reason there is no piss stream out the back? It clear (no blockage) because on a hose its has a piss stream

loveboat123! said:

thanks, I will go out on the lake today and feel the engine for the heat level. If its not too "hot" (burning ~above 140) then it must be getting cooling water? The tell tale is nice to see, but I wonder if this is just the way the motor is and live with it..... I bought this motor for $1200 and its over 20yrs old. I expected it to have issues but nothing to serious that would destroy itself. If the impeller is new, then what would be the reason there is no piss stream out the back? It clear (no blockage) because on a hose its has a piss stream

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OK. Ran the boat for over an hour a low pontoon speeds and the engine is still not pissing water (more like a spitting of hot water and exhast). Took the cowling off the engine and it is HOT. Not burning hot, but you cant hold your hand more than a few seconds. I ordered a new thermostat, but that would not explain the no piss stream out the back. When I get it I will start it without the thermostat in place to see if water is coming out of the thermo hole. If there is NO water then its some other blockage between the new impeller and the head. Any advice here is welcome!