Evinrude Motor Trouble

I have a 95′ 40 horse Evinrude 2 stroke. About two weeks ago, the overheat alarm went off and the boat would not operate over half throttle. Let it cool down and it ran fine.
Took it out yesterday and it started up fine, but I could only get going about 5 mph. If you tried to give it more throttle, it would just chug and chug. It would start to wind up then drop back down every other second. No alarms went off this time though. It almost seemed like it wasn’t getting enough gas to run faster, but I have no idea.

The two problems seem to be separate, but the fact that they happened so close together makes me think its related.
Any ideas would be really helpful, as I am not going to pay someone to work on it anytime soon.

are you pissing out the usual amount of water ???

Is the motor peeing? Check to see if the water intake is plugged also.

Red; I’d check the fuel line. Sounds to me you are getting air in. Check and see if the primer bulb stays firm, could be the o rings in the fuel connections also.

I ran into this once on an old merc. Problem I had was on the fuel pickup inside the gas tank. Took the hose out of the tank and it was rotted. Swapped in a new hose and problem was solved.

“I have a 95′ 40 horse Evinrude 2 stroke. About two weeks ago, the overheat alarm went off and the boat would not operate over half throttle. Let it cool down and it ran fine.”

It’s a self preservation program built into the engine. The engine is telling you something is wrong. Take a dealer about 5 minutes to diagnose the issue. You then could repair it yourself. You keep on running it and you will end up buying a new motor.

Sounds like your water pump or thermostat went out or the water pump was plugged and it overheated which may have caused the cylinder walls to get scored, especially if it was ran a lot or WOT. Check the compression and compare to what should be normal. Also, check how hot it gets with your hand. Good luck

The water was streaming out just like normal when it overheated the one day, and it was coming out good yesterday too. So it doesnt seem to be an issue that its not pumping enough water.
The motor ran fine after the overheat warning came on the one day, so I don’t see how the computer would still be reading that. And like I said I have no warning horn now, so it seems to be something different. I’m no mechanic, but just logically it seems different.

We had the impellers replaced in 2006 because the motor was overheating and not pumping enough water. But I can’t see that being the issue, with the water coming out good still.

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Red; I’d check the fuel line. Sounds to me you are getting air in. Check and see if the primer bulb stays firm, could be the o rings in the fuel connections also.

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This is something I thought of as well. So the primer bulb should always stay solid when you are running it?

It doesn’t explain why the motor overheated though, does it?..

Keep the ideas flowing guys, Thanks.

i’m no motor mechanic, but i usually get home off the water.

if i remember correctly a similar situation, my mechanic told me that they will run hot if too lean (under pressured feed)

yes, the bulb should stay REASONABLY solid… is my practice anyway. It’s what gets the fuel UP 18″ and into the motor besides the vacuum the engine creates. IMHO

NOT FOR SURE, just saying…

How long were you at WOT???

Stu-

I think I ran about two miles back down river towards the boat landing, slowed down to pass a guy in a slough, then he waved me by and I cracked on it for a couple hundred yards. The alarm went off maybe 200yds from the boat landing.
I usually run the thing just a little bit under WOT, say WOT I do 29mph, I usually let off a little maybe down to like 26mph. I think when the alarm went off, I had it close to WOT.
I’m not sure if its bad to run it that hard or not, I’ve just been told that they are set up and designed to handle it.

Just for future reference incase anyone has a similar issue, I got the motor fixed and it was the sensor in the oil tank apparently. I couldn’t figure it out, so I brought it to a guy to check out. It was a easy fix, but ended up costing me way more than I wanted to pay because he couldn’t figure out what was wrong with it. Just replaced the assembly that goes into the oil tank and it was running fine.

Thanks for the tips.