3hp Flathead Briggs won’t start

Will'smotobikes19

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Apr 9, 2018
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Think the motor is from 1988 but it’s on a rupp minibike. Cleaned the carb and all jets seem to be clear and the float needle is working. Has spark and plug is wet. I am baffled why it won’t start. Ran when I first brought it home but one day refused to fire. Seems to have good compression and has oil.
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Btw this site flips pictures on the side for some reason idk why.
 
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RAT RYDER 101

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Jul 12, 2017
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177
Check the coil. Also the gap on the mags> some spider guts might be in there.... (carry on) Rings might be loaded to. Just sayin.. I have that exact carb on a 10 horse Briggs cast block mounted on a SPEEDX from the early 60s.
 
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Will'smotobikes19

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It was weird I sprayed carb cleaner into the spark plug hole and it still wouldn’t start. The jet on the bottom of the carb? The only thing I could think of valves need adjusted.
 

Will'smotobikes19

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The spark is a bright white, not blue I don’t know if that could be the problem. It has an old fashioned killswitch- a metal tab bolted to the head.
 

darwin

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May 26, 2008
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Notice the stickers saying easy spin. My ass, those motors were the original Bow flex machines.
 

darwin

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May 26, 2008
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The spark is a bright white, not blue I don’t know if that could be the problem. It has an old fashioned killswitch- a metal tab bolted to the head.
Adjust the point gap, make sure the cam rider [plastic piece that rides on the cam] is good so the points are opening and closing. Bad/weak spark could be a condenser problem too if it's old and can't hold a proper charge.
 
D

DRK

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Flywheel could have a light coating of rust on it from setting. Sand the rust off the flywheel & coil magnet. Set the gap by sliding a business card between the magnet & flywheel, hold down on the magnet & tighten the 2 screws. Pull out the business card. Also looks like that one has the points setup. The points could be burnt or corroded. Use a fingernail file to clean the points. Slide the file between the points, push down on the points & pull the file through the points. If it still has weak spark, as Darwin said, condenser could be bad.
 

curtisfox

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May 13, 2010
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Could check out go-kart supply, they may have a conversion to upgrade eliminate the points..........Curt
 
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