1951 seaking deluxe 5hp

[boating thad]

i need some help boat engine runs fine at lower elvation but when we take it to a higher elvation lake runs like crap tends to misfire and has no power and gets worse throught out the day ran great last year changed 2 stroke oill from evinrude oil to merc two stroke oill changed spark plug and ran like crap this season
thanks thad

 

[CATransplant]

Re: 1951 seaking deluxe 5hp

Outboard, especially small two-stroke outboards, need carburetor adjustments for best operation at high elevations. Essentially, they need both low-speed and high-speed needles adjusted to run more lean than at lower altitudes.

Best way to to this is on the water...in fact that's the only way to do it properly. Have you done any carb adjustments?

Also, it's entirely possible that between last season and this season, your carb has gotten gummed up. A good disassembly, cleaning, and installation of a carb kit will help.

 

[boating thad]

Re: 1951 seaking deluxe 5hp

i mesed with the knob for the fuel adjustment and still didn't seem to help

thanks thad

 

[F_R]

Re: 1951 seaking deluxe 5hp

Probably has nothing to do with elevation or fuel or carburetor. Have you changed the coils yet? Those motors ALL have bad coils unless they have already been changed. That is why it is misfiring.

 

[steelespike]

Re: 1951 seaking deluxe 5hp

What he said.Yes if the coils are original they will need changing.Easy if you are mechanically inclined.Readily available at BRP dealers and here at iboats.
Parts for the similar year Evinrude/Johnson motors.