This has been a great engine
for 10 yrs, but it's developed a problem I can't solve. It starts on first pull and idles smoothly. When I open the throttle, the engine
sputters and it takes a long time to get my 10ft Livingston dink on a plane. After dink starts to plane, engine will rev up and seems to have almost full power, but not quite. While planed off, the engine does not run as smooth as usual. After it planes off the dink the first time, the 2nd and subsequent attempts to plane off the dink comes out of the hole within 10 seconds, but still not developing full HP.
I have done the following obvious fixes:
: removed carb and cleaned with spray cleaner at least 3X; put rebuild
kit in carb (new float, shut off, and gaskets); replaced diaphragm
in fuel pump
; replaced fuel
line to tank; cleaned internal and external fuel filters; put fresh fuel in the tank.
Ignition: Replaced plugs; checked spark using a screwdriver in socket and spark jumped 1/2" to block; bought a spark tester light that connects to plug
lead on one end and on the plug
on the other. I ran the dinghy
at night using this light on each cylinder and could not see any misses; I checked AC voltage output of CDI
and got around 200 volts and close to shop manual values (one cylinder varied much more than the other, but maybe due to a digital meter); I ran engine under load and removed spark leads one at a time and RPM
loss sounded equal; I pulled off the flywheel and looked at the coils and mechanism that operates the pulsar coil... it looked OK, but there was some play in the plastic pulsar-coil lever around the crankshaft. I tried checking the timing according to shop manual, but the info "did not compute" and when I put the #1 piston at 30 degrees BTDC, the timing marks were way off. I didn't mess with it because if it was really that far off I don't think it would run. I'm not sure I understand the procedure so I'll give that another try.
Anyone have any ideas on what to check next? I'm still not sure whether it's fuel or ingnition. Since the problem is intermittent, it has become more challenging.