Engine won't idle, but runs fine at higher rpms

My wife and I took out jon out fishing for the first time this year yesterday. It started and ran great. Howerver, later in the day, I noticed a slight smell of gasoline every once in a while . Upon inspection, I found that the prime bulb (which is less than 1 yr. old) has started to badly decompose around the fitting closest to the motor. If I would pump the bulb a small amount of gas would shoot out.

This afternoon we took it out again. Today when I would squeeze the bulb to start the cold engine the leak was worse. The engine started, but after it warmed up and I went back to idle it would shut off. I finally got it to idle low enough to get it into gear, so off we went. It runs great at higher rpms but cuts off when I go down to idle.

We drift fished for a couple of hours, not using the motor. When we were ready to move on, the motor had lost it's prime and the primer bulb was soft. I could see where it had leaked gasoline out of the bulb. I had to squeeze the bulb several times before it would build any pressure, gas would shoot out of the bulb with just about every squeeze.

I plan to replace the bulb this week, but my question is; is bad bulb causing the non-idle problem?

Yes it probably is. At idle the hole is large enough that the pump is sucking more air than fuel. At higher RPM the pump can keep the fuel bowl full enough to keep the engine running at high RPM. Alcohol fuel is your nemesis! Find a station that sells not alcohol fuel and the fuel components will be there for the long run

Pappy said:

Yes it probably is. At idle the hole is large enough that the pump is sucking more air than fuel. At higher RPM the pump can keep the fuel bowl full enough to keep the engine running at high RPM. Alcohol fuel is your nemesis! Find a station that sells not alcohol fuel and the fuel components will be there for the long run

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Thanks, that was my thoughts, but wanted to make sure I was on the right track.

You need to be sure to look at the whole fuel line and not just the bulb. If the bulb was eaten up, the line may be too. Take note of the fittings on either end and you can find a fully assembled replacement pretty easily.

sf

I had simular issues with my Mer 20 and it turned out to be the quick disconnect at the motor.

LIke Sawdust Farmer said be sure to check the entire fuel system for air leaks

Leak probably is the problem Be sure your next bulb is ethanol proof.