2001 15hp Evinrude four stroke - Overheat or am i a total noob?

[bigdeuce200]

My 2001 Evinrude 15hp Four Stroke starts and idles very nicely!

I bought this motor used, then put it on my boat and:

When I wide open throttle, the motor shuts down ("bogs" down over about 2-3 seconds) after about 30-60 seconds.
So I came to these forums and did the following work.

Facts:

• Compression is 160 and 166 (cold)
• I have cleaned and re-assembled the carburetor with great care.
• I have replaced spark plugs (old ones looked fine though).
• I have replaced the fuel pump.
• The tell-tale always has a strong steady flow, which gushes at open throttle.
• The thermostat starts to open at 149 Farenheit and is fully open at 160 farenheit.
  • The thermostat and the hole it came out of were clean without any signs of salt or gunk.
  • The hose from the thermostat to the exhaust housing is kinked about 1/2 closed at the exhaust end. There seems to be no alternative here, due to the lower cowl squishing against it.
• I have changed the oil and filter (although the old oil was quite clean and clear).
• The spark plug leads were tested at a dealership and found to be functioning correctly.
  
• Touching my finger to the engine block after it stops, feels very hot.

Now the motor sounds like its running much, much nicer than when I first put it on my boat, BUT!!:

Testing with the motor in neutral in a garbage can, it is still "bogging down" over about 2 seconds to a stop after about 60 seconds of wide open throttle.

My own ideas are based on what I have researched here for hours and hours and hours:

1. Possible ignition problem (I am going to buy a spark tester and some kind of tachometer).
2. Waterways inside the engine are plugged (I don't know the procedure to diagnose or repair this).
3. The garbage can is too small, and revving the motor to WOT in neutral is causing the overheat.

I am stuck. I have tried my very hardest. Please help with any advice or direction where to go from here.

Maybe I should just put it back on my boat and try again?

Thanks,
Barkley Sound

 

[BonairII]

Re: 2001 15hp Evinrude four stroke - Overheat or am i a total noob?

Do not rev to WOT while in neutral!!!! There is no load on the motor while in neutral and you're liable to blow the motor that way.

How are you even able to rev so high while in neutral? I would assume that your motor has some kind of safety to prevent you from doing it in the first place.

 

[Ldavidgrover]

Re: 2001 15hp Evinrude four stroke - Overheat or am i a total noob?

Sound like your over propped

 

[raczekp1]

Re: 2001 15hp Evinrude four stroke - Overheat or am i a total noob?

there is a temperature gun to check how hot is your block.
borow one and try to check how hot is.

if you want to try, i would drop lower unit , and atache garden hose to water pipe after removing lower unit, run water at 50% of valve opening and see if water is circulating
run motor with water on and see if symptoms are still

go to boats net and go for diagram of your motor

 

[steelespike]

Re: 2001 15hp Evinrude four stroke - Overheat or am i a total noob?

When in a barrel the water needs to be up to the mount bracket.
Have you tried a little choke when it falters?
Have tried squeezing the primer bulb?
Does it crank easily after stalling?
Will it restart right after stalling.

 

[AlTn]

Re: 2001 15hp Evinrude four stroke - Overheat or am i a total noob?

raczekp1's idea of using an IR Temp Gun is a good one..once you have one you won't regret it. Post back temps at bog.You could also be experiencing a venting failure with you fuel can, try running it with the cap almost off, or try another tank.