Mercury 45HP Dies out when running whide open

[jathomps04]

I have a 45HP 80's Model Mercury Outboard. It is a good motor but has one problem. As I am running the engine fast or at full throttle it dies out. I have a new gas tank and have multiple hoses that I have tried. What could the problem be?<br /><br />I heard somewhere that I may need to decarbonize the motor. Is this true? How could I do this?

 

[schaiss]

Re: Mercury 45HP Dies out when running whide open

Decarb is sold in spray cans at local boat supply stores. Pull all the spark plugs, spray liberally into each cylinder. Replace the plugs and fire that bad boy up! Expect more smoke than you normally get. Take it fot a spin. If you haven't changed the plugs lately... they only cost about $1.50 each, and this would be a great time to do it.

 

[jathomps04]

Re: Mercury 45HP Dies out when running whide open

I take it that my sumptoms may be able to be solved by a little decarb spray and spark plugs. I will get on that and let you know how it goes. Thanks!

 

[MercNdude]

Re: Mercury 45HP Dies out when running whide open

If the carb spray didn't work for you, check/replace the fuel lines and filters. This is a cheap trouble shooter and most times works. If not, then you may have to go to electronics. Most times, this is not the culprit - but it IS in some cases. Stick to fuel causes first. Fixing them is cheaper and more likely to be the trouble. Check all the way to the line that directly feeds the fuel pump. Next I'd see if the problem goes away if someone pumps the bulb when the engine starts to die. You'll need a partner to help. If this keeps things going, you have a fuel issue somewhere.

 

[jathomps04]

Re: Mercury 45HP Dies out when running whide open

It does work to keep the bulb pumping when I am accelerating. If we do this, the engine does not die. It is not an electics problem because this engine is small and does not have any electrics. Third, in response to fuel filters and gas lines, I have tried two gas lines and neither work and I think that the only fuel filter there is is in the bottom of the tank(the screen). Let me know what else to try.