jim j geezer
Petty Officer 2nd Class
- Joined
- May 16, 2012
- Messages
- 189
This's a '68
Model#: 574.55930
Serial#: 686007101058
Shortly after I got it I had it running like a sewing machine. Then set it aside for a month or so. Tried to test run it and it'd start & run with raw fuel shot into the carb, then would die. Dug into it and learned that 1 of the 2 sets of reed valves were cancer-ridden. Searched without success for replacements. Put on my McGyver hat and glommed onto some .005 shim stock. Used a Dremel and fabricated a replacement. Full disclosure: The .005 material is thinner than the original, which is about .008. In any event, got it running like a top again. Then set it aside. Tried to demo it and faced the same issue: Start & run with a prime, and then die. Tore down the carb & examined the reeds: Slightly mis-shapen - as though they were slamming shut with more force than they could withstand.
Years ago I learned a 'trick' to improve outboard performance
ouble up the reed valves. Now I have it in mind to do just that or to acquire some .01 shim stock. But before I do I have a question regarding the vacuum pulse that drives the fuel pump. Where does it come from?
This's a side-mounted carb notorious for being a royal pain to work on. It's living up to its reputation.
Fuel pump diaphragm appears to be in good condition. New fuel line, primer bulb and fittings. It won't run long enough for me to pump the primer bulb to coax it along.
I'm a McCulloch fan and have been for decades, but this one makes my head hurt.
Thanks.
Jim Geezer
EDIT: How in the WORLD do you get the float out?
Model#: 574.55930
Serial#: 686007101058
Shortly after I got it I had it running like a sewing machine. Then set it aside for a month or so. Tried to test run it and it'd start & run with raw fuel shot into the carb, then would die. Dug into it and learned that 1 of the 2 sets of reed valves were cancer-ridden. Searched without success for replacements. Put on my McGyver hat and glommed onto some .005 shim stock. Used a Dremel and fabricated a replacement. Full disclosure: The .005 material is thinner than the original, which is about .008. In any event, got it running like a top again. Then set it aside. Tried to demo it and faced the same issue: Start & run with a prime, and then die. Tore down the carb & examined the reeds: Slightly mis-shapen - as though they were slamming shut with more force than they could withstand.
Years ago I learned a 'trick' to improve outboard performance
ouble up the reed valves. Now I have it in mind to do just that or to acquire some .01 shim stock. But before I do I have a question regarding the vacuum pulse that drives the fuel pump. Where does it come from?This's a side-mounted carb notorious for being a royal pain to work on. It's living up to its reputation.
Fuel pump diaphragm appears to be in good condition. New fuel line, primer bulb and fittings. It won't run long enough for me to pump the primer bulb to coax it along.
I'm a McCulloch fan and have been for decades, but this one makes my head hurt.
Thanks.
Jim Geezer
EDIT: How in the WORLD do you get the float out?
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