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1988 120 HP Looper Johnson

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alwaywrknonit2

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"Help me out here guys. Im rip

"Help me out here guys. Im rippin my hair out. My motor went down on me in Sept. It just shut off. I had a mechanic test it and he said the stator was bad. I put a new stator in it and cleaned up everything. This motor has a new power pack, plugs, wires, coils, rectifier, fuel pump. I got spark and the motor started. It seemed to run fine the other day. I took it out for a test run. It idled fine and went up to 1/4 plane speed. After 10 minutes, it slowed down. I gave it more throttle and it came back up. It then bogged down and shut off. I squeezed the ball and it started right back up. It raced but you could tell it was fightin to run. It then shut off. I drifted into the marsh and began workin on it. Many times, it would start and fight to run but shut off. It never started again. The gas in the tank isnt but 3 months old. Once towed in and back at the house, I checked the spark in all the cylinders and I have spark. But nothing to write home about.Im thinkin the flywheel may be to blame. It shows signs of wear and tear. Could this keep the motor from firing a good hot white spark? The fuel tank was full of fuel. Im thinkin the plugs fouled because of lack of hot spark. I pulled the plugs when I got home and the plug on the top left(standing behind the motor) was dry. The others were wet. Once trying again, they were all wet."
 
And what about a sheared flywh

And what about a sheared flywheel key?? Timing tested / checked??
 
"Flywheel key checked and in p

"Flywheel key checked and in place. Checked by me. I know. I had to make one to fit the flywheel.I triple checked it.
"
 
"I think I would start with a

"I think I would start with a spark checker first to establish at least that the 'power' is there. If not, do a voltage output test of stator.
Next would be a timing light to get the idle timing confirmed. If out, I would have a closer look at the center magnets (sensor) of the fly wheel. Have the center come loose?
During testing disconnect the stop circuit, black/yellow, from the power pack."
 
"Ok. I will se what I can find

"Ok. I will se what I can find out. When you say center magnet, I assume you mean the one that is on the hub. That one is tight. As far as timing goes, the timing being off would make the motor just all of the sudden slow down and shut off? How would I check it if the motor wont start? I dont think I can. As far as the center magnet goes, I know I sheared the wedge pin. Could the magnet have been dislocated? Is there a specific spot it has to be in? I know it has 1 notch on either side of the thing."
 
"Test ignition as follows:
Ma

"Test ignition as follows:
Mark the flywheel where each and one cylinder is at TDC. (You already have a marking for cyl 1).
Attach a timing light and crank the engine, and move the timing light pick up from cylinder to cylinder. At each cylinder ONLY the respective mark should be visible, not any other cylinder marking. This will tell You if You have a 'double' fiering problem. If two cyl's fires at the same time, it might not be enough 'power' from the charge coils to give a blue spark. If Cyl 1 fires around 4ATD , and no double fiereing, powerpack is ok, sensor coil is ok, hub magnet is in position.
If You have a double fireing situation, powerpack is 'gone'."
 
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