motor stumbles at higher rpm

[RI_Bay_fly]

Hi. It's a 2001 Merc 4-stroke 15-hp (lease return). It took 1/2-dozen trips to develop my first problem: the motor sounds like it cut down to 1 cylinder when I pushed it hard yesterday. After running rough/reduced for a couple of mins., it jumped back to normal without touching anything. I wasn't pushing it full throttle when it happened, more like 1/2 to 2/3. We put the boat back on the trailer and went and bought 2 spark plugs and borrowed a socket - the plugs looked fine. So we purchased some dry gas and put the boat back in. It was too choppy to really push the motor after that, but we motored for two hours slowly with no problem. At home, rinsing, I revved it high enough that it sounded "funny" - should I get a tachometer, or should I be careful about revving it too high??

 

[wilde1j]

Re: motor stumbles at higher rpm

Rev too high w/ no load and you may not have a motor to worry about!

 

[RI_Bay_fly]

Re: motor stumbles at higher rpm

Thank you WildOne. This is the kind of practical knowledge these forums are great for. I took the boat out yesterday and ran near full throttle for a bit - worked great - must have been water in the gas. I do spray my hose all over the motor and gas tank when I rinse. Must have left the vent cap open when rinsing. I hope everyone is enjoying SHARK WEEK on the Discovery channel. I think Nigel really dug that blonde chic, huh?