68' 500 stalls under load

[Damien77]

68' 500 2476762 s/n. Stalls under load, when I have someone pumping the primer bulb runs fine. Is this a float issue, pump issue or bulb and lime issue.

 

[racerone]

Open low speed mixture screws 1/8 turn at a time and test run.

 

[Damien77]

Ok I will try that. I did replace the inlet needle and seats for both carburetors and had to readjust the float stops which was rather difficult to get correctly.

 

[Damien77]

Thanks racerone, that did solve the stalling issue. Seems like about 3/4 throttle it wants to stall but won't(runs rough) I just got this unit. It seems like it doesn't spin at full RPM and I feel like whoever had it compensated for the power loss by improperly adjusting some of the adjustment screws.. My seloc service manual is kinda confusing at times

 

[fastjeff]

You might have too much prop on it.

Jeff

 

[Damien77]

Perhaps, it's pushing my 18' pontoon and it has what I believe to be a 15p prop.

 

[fastjeff]

WAY too much prop! I used a 15 pitch on my 9 foot speed boat with a similar motor.

Jeff

 

[Damien77]

Thank you Jeff I appreciate your support. Do you have a suggestion? I was thinking 13p? Still to much

 

[Damien77]

I have the not so easy to find 11 spline prop shaft. Any suggestions on where to locate one?

 

[fastjeff]

E-Bay.

Alternately, you can get the more common 13 splined prop re-hubbed for 11 splines.

Jeff

 

[Damien77]

So how do I re-hub the new one? I need to get the prop and buy a separate hub with the 11 spline? I have a local marina looking for one in their organ donor pile.

 

[fastjeff]

A prop shop will remove the old hub and install the new one.

Jeff