Trouble shooting an 89 classic 50 tiller with electric start. I was using the boat and ran fine was running the motor close to WOT coming back from fishing. Docked the boat. ABout 4 hours later went to head out and motor started up but wouldn't accelerated. Felt like it was loaded down. Ran very boggish . I shut the motor down...inspected the obvious things like gas connections, tank vent open etc. Started it up and still weak power and running rough. Won't idle and coughs and puffs. Now hard to start. Used the trolling motor to get back to the launch. Took the boat home and here is my diagnoses so far.
Found a few wires suspect coming from the trigger. Replaced them and check resistance. Trigger is within spec. Removed stator and wires seemed OK. Resistance checks of high and low sped windings and charge coils all within spec. No signs of cracking or melting of anything on the stator around the windings. Put everything back together hoping perhaps would fire....puffs and coughs but won't catch. Fuel is good. Checked compression all at about 135psi.
Got a timing light to check switch box by marking flywheel at each cylinders TDC position hoping I could get it to run enough to see if it was firing the plugs at the right time....couldn't get it running long enough to check properly.
What next? I didn't check for 7/16 spark be cause figured if stator homed out should be OK? I am thinking it's not a ground issue since it does fire/caugh/puff. Thoughts?
I am leaning towards switchbox but could the stator still be the issue? When I did get it running for a few seconds on multiple occasions it appeared that it wasn't firing the cylinders at TDC on any of the cylinders. But I wasn't sure as I am unsure the timing light was even pulsing...almost seemed like it was on steady but dim.
Found a few wires suspect coming from the trigger. Replaced them and check resistance. Trigger is within spec. Removed stator and wires seemed OK. Resistance checks of high and low sped windings and charge coils all within spec. No signs of cracking or melting of anything on the stator around the windings. Put everything back together hoping perhaps would fire....puffs and coughs but won't catch. Fuel is good. Checked compression all at about 135psi.
Got a timing light to check switch box by marking flywheel at each cylinders TDC position hoping I could get it to run enough to see if it was firing the plugs at the right time....couldn't get it running long enough to check properly.
What next? I didn't check for 7/16 spark be cause figured if stator homed out should be OK? I am thinking it's not a ground issue since it does fire/caugh/puff. Thoughts?
I am leaning towards switchbox but could the stator still be the issue? When I did get it running for a few seconds on multiple occasions it appeared that it wasn't firing the cylinders at TDC on any of the cylinders. But I wasn't sure as I am unsure the timing light was even pulsing...almost seemed like it was on steady but dim.
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