4.5 hp slows and then dies

[Grant Brown]

1984 4.5 hp Merc.<br />I picked up some sea weed in the cooling system of my 70 hp a couple of weeks ago and decided to run home on the kicker. <br />It was a little hard to start and wouldn't run at all on the troll setting. When I got it to run without the troll lever on, it would run fine at first then eventually the revs would die off slowing the boat down. Normally I GPS at 5 mph in my 16 footer at WOT. This time I could only do maybe 4 mph tapering off until it got down to less than 3 and died. If I let off the throttle at all it would die and wouldn't re-start until it cooled off for a few minutes.<br />It seemed to run fine and rev up without any load on the prop, but as soon as I put it in gear it did the same thing again. <br />When I got home I fired it up in the garbage can and flushed it, then pulled the spark plug which was black and oily. I run mid-grade fuel with Quicksilver oil at 50:1.<br /><br />Thanks,<br />Grant

 

[Grant Brown]

Re: 4.5 hp slows and then dies

^ Heading out next again weekend & need the kicker to work.

 

[Grant Brown]

Re: 4.5 hp slows and then dies

^

 

[andy6374]

Re: 4.5 hp slows and then dies

You may a timing issue, or more likely you have a weak spark and in effect you are igniting the fuel/oil poorly, which will foul up your plug. <br />Do a search for testing spark strength.<br /><br />-andy