Suzuki DT8 2stroke -circa 1983 start/run problem

[old-gubbins]

Engine reluctant to start, fires occasionally, but usually only on full throttle, revs 5 to 10 seconds then dies.

CDI unit was faulty, just installed a brand new one, cleaned carb (twice), new impeller, new head gasket (took head off to check cylinders before buying a new CDI unit!).

After being reluctant to start, it ran OK on full load on the boat for about 20 minutes after the new CDI unit installed, then symptoms returned.

Fuel pump pulses fuel when starter pulled. I have checked continuity on the wires to the charge coil and trigger coil whilst tweaking and pulling on the wires and they look OK.

To me, the symptoms seem like lean fuel supply, yet the (new) plugs (especially the lower one) look wet.

Any ideas, please, on what I am missing.

Why have I bothered spending "a fortune" on a new CDI unit: Because any 8hp 4 stroke (two cylinder) is about 22 lbs heavier, and the 6hp Tohatsu 4 stroke single cylinder engine which I have as a kicker for another boat vibrates so much more than the old DT8.

Any help appreciated, thanks. O.G.

 

[old-gubbins]

Re: Suzuki DT8 2stroke -circa 1983 start/run problem

Update:
We thought the spark varied in intensity and have removed, checked and cleaned the ignition coil and the sensor/trigger, resistances within spec., spark now appears consistent and strong.

Problem symptoms unchanged. Fires occasionally, runs roughly for a few seconds then dies and then will show no signs of firing for a few minutes. Upper plug dryish, lower plug wettish.

Have not yet looked at reeds. Could it be faulty reeds?
Could it be leaking crankcase oil seals?

Any thoughts appreciated.

O-G