Motor running bad

[Clay Resmondo]

I have a 1975 Sears Ted Williams (Eska) 5.5 (mod.# = 217.58571.0) and the motor is a Tecumseh (mod.# = T643-20B). As stated in the title my motor is not running so good. It runs like a champ as long as the gas tank is topped off but it spits the fuel out of the vent hole in the cap so it runs out of gas really quick, well i got a new gas cap for it but the one sears sent me is slightly diffrent it has a vent screw. So how do I use this style gas cap? The motor has a metal gas tank. Also my motor smokes heavily, (my mixture is 32:1)should this be a concern or is it just because it's an old 1975 two cycle motor? One more thing I was wanting to replace the needle, valve, and seat in the carburetor I have the stuff but should I do this if replacing this gas cap works? I hear opening up the carburetor is not a good idea unless you have to. Any truth in this? All help and advice would be appreciated.

Thanks, Clay

 

[freddyray21]

Re: Motor running bad

those are difficult motors to find parts for. I would imagine the fuel pump element in the carb is the main cause of your problem.

 

[F_R]

Re: Motor running bad

It would help to know what you have. Is it a gravity feed tank on the motor or a remote tank and hose? Is it a float feed carburetor or is is a diaphragm carbutetor?

Run with the gas cap vent open.

 

[Clay Resmondo]

Re: Motor running bad

F R it is a metal gravity feed tank on the motor and it is a float feed carburetor. what about when storing the motor vent closed or open?

 

[steelespike]

Re: Motor running bad

Vent closed when storing.If your running it in a tank it will seem to smoke
a lot.With the motor warm at speed adjust the highspeed jet ,not too lean.then in gear adjust the low speed.Should help the smoking a little.
These motors are finicky under performers that vibrate terrible, you may have noticed.Get her running good for as little investment as possible.most would suggest sell it and put the money toward a more main line motor like the Evinrude/Johnson 5,5.5,6,or 8 hp.