Quick question on an impeller

I have a 15hp Johnson outboard that runs real well and is very strong, but I noticed the past couple days when I've had it out that the water it is peeing out the back is starting to get warm. It has a strong flow coming out the back, but it's warmer than I'm used to. My cousin and I put a new impeller in it last fall before putting it away for the winter, but should I replace it again? I've banned the boat to no water until I get it fixed or find out that it is normal. The current water temp in the lakes I've been fishing is right around 58 degrees so I know that it's going in cooler than it's coming out. Should I just go ahead and replace the impeller? Is the pee water usually warm and I'm not remembering correctly? What do I do if it's supposed to be cooler and the impeller isn't the problem?

Thanks for any help you fine folks can give me!

Water coming out of the motor should be warm (once the motor's warmed up). It shouldn't be too hot to hold your hand under. If you replaced your impeller this past fall before putting away, there should be no need to replace it again unless you've run the motor without the lower leg in water. If the water is coming out hot (can't keep your hand in the stream for more than 1 second), then you may have to start looking at the possibility of blockages somewhere in your cooling system.

I'd say from your description that you should be ok.

kofkorn said:

Water coming out of the motor should be warm (once the motor's warmed up). It shouldn't be too hot to hold your hand under. If you replaced your impeller this past fall before putting away, there should be no need to replace it again unless you've run the motor without the lower leg in water. If the water is coming out hot (can't keep your hand in the stream for more than 1 second), then you may have to start looking at the possibility of blockages somewhere in your cooling system.

I'd say from your description that you should be ok.

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Sounds good. That's what I was hoping someone would say. The more I think about it, the more I'm convinced that what I'm remembering is after I replaced the impeller, I ran it for about 10 minutes in a barrel to make sure everything was running correctly. I think I'm just remembering putting my hand in the stream right after start-up and it hadn't gotten a chance to really warm up yet. In any case, I went ahead and ordered a new impeller so I'll have a spare on hand if ever needed.

If the water coming out the pee hole DOESN'T get warm it could mean your thermostat is stuck closed - and that is bad.

You have a thermostat in your engine. It is there primarily to warm the engine at idle speed. The top of the powerhead should be running in the neighborhood of 135f give or take. Engine will cool down from that figure once on plane.

Thanks again guys! I was getting all worked up over nothing it seems. :roll: