1956 fastwin 15 hp timing & fuel ratio

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dasman7580

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I have recently installed all new ignition components, rebuilt the carb, new headgasket, and new impeller. Took it out to the lake and it runs rough at full throttle. I set the point gap at .020" at the word "top" on roller bearing. Is that the correct procedure?? I'm running a fuel mixtur e of 24:1 based on the original specs. The guy I got it from as well as several internet sources say to use 50:1???? Can someone set me straight????
 
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F_R

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Re: 1956 fastwin 15 hp timing & fuel ratio

Points .020" at the widest opening is correct
24:1 is correct.

You have adjusted the high speed carb knob, haven't you?
 
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dasman7580

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Re: 1956 fastwin 15 hp timing & fuel ratio

After gently seating I backed it off 1 full turn and tightened the screw. Then adjusted either direction while running with no change. The plugs also appear to have unburned fuel on them.
 
1946Zephyr

1946Zephyr

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Re: 1956 fastwin 15 hp timing & fuel ratio

Low speed generally sets at 1 1/4 to 1 1/2 turns out from lightly seated and high speed sets at 1/2 to 3/4 turn out. Good old motors and very reliable. If you go through the expense of giving it a thorough tune up, (which it looks like you did) you'll have a very reliable motor for years to come.

If it's running rough at full throttle, turn the high speed in 1/8 turn every couple minutes, till it smoothes out.
 
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F_R

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Re: 1956 fastwin 15 hp timing & fuel ratio

dasman7580 said:
After gently seating I backed it off 1 full turn and tightened the screw. Then adjusted either direction while running with no change. The plugs also appear to have unburned fuel on them.
Click to expand...

Turning the knob should definitly change the way it runs. Too rich will make it "4-cycle" (run rough). Too lean will make it quit running. Since it did not quit running, it sounds as though you didn't try it lean enough. Turn that sucker to the right (lean) till it starts to lose power, then back to the left till it regains full power. THAT is the correct setting. Counting the number of turns serves only to make it close enough to get it started, then adjust from there.
 
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dasman7580

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Re: 1956 fastwin 15 hp timing & fuel ratio

I was reading some other posts and saw a "link and sync" mentioned. Could this be part of the problem?? If so, what's the procedure??
 
nwcove

nwcove

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Re: 1956 fastwin 15 hp timing & fuel ratio

when you did the carb work ...did you pull the welch plugs and clean out those passages? id focus on the carb/sttings before getting into the link and sync. (and if you're using a pressure tank, check all connections for air/fuel leaks)
 
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freddyray21

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Re: 1956 fastwin 15 hp timing & fuel ratio

pulling welch plugs is good for idle speed, but does not affect high speed. At one turn out it's a wonder it runs at all wide open. I find mine run best at about 3/8 to a half turn, but like Frank said turn it in until it stumbles then back it off until it smooths out.
 
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dasman7580

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Re: 1956 fastwin 15 hp timing & fuel ratio

Got it out on the water last weekend and it runs like a champ???
A little a little adjustment to the high speed needle and it took off like a rocket. Thanks everyone.
 
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