I have a two stroke 3 cylinder 30hp Suzuki motor that is driving me towards suicide...
The symptoms are as follows; The top cylinder (closest to flywheel) refuses to fire. The engine start on first pull perfectly but immediately settle down on two cylinders only and when opening the throttle, the engine will momentarily fire on all cylinders and go like greased lightning, but then cut down to two cylinders. Closing the throttle somewhat it will sporadically fire the top cylinder for a second or so - much like turning an ignition on on off.
I suspected a fuel starvation problem but even when running on the lower two cylinders, I squirted some petrol into the carb and nothing happens, actually get worse. I fitted a new coil and it has plenty of spark but strangely, when its idling on two cylinders and I pull the top sparkplug lead off (sparks all over) and bring it towards the sparkplug and about an inch from the plug the spark would jump and the piston firing up momentarily again but stop although the spark is still jumping the distance or even when pushed onto plug. I changed sparkplugs to no avail as well as the coils with no difference. What can be at fault
I already did the following;
1. Checked compression and it fine - same across all cylinders
2. Completely stripped and cleaned the top carburator a few times already
3. Checked the coils primary and secondary - all primary ohm readings as per manual but only one coil have a secondary ohm reading as per manual - even replacement coil does not read on secondary, but that said, all have plenty of spark and changing the coil combinations makes no difference.
4. Checked the charge coil under flywheel and both resistance and voltage output within spec.
5. Gearcounter pickup resistance and output voltage within spec.
6. Pickup coils (trigger coils) all three resistance within spec (195 - 197 ohms) similar to gearcounter pickup, but the output voltage only 10% of their spec on my tester - 0.45V (spec 2.5V >) on all three pickups, compared to the gearcounter coil's 4.6V (spec 2.7V>). Even with low readings, the bottom two pistons runs pefect.
7. Changes sparkplug - hotter and colder to no avail.
8. All spark coils and pickup coils well grounded and can not find any loose connection.
Worth mentioning; with only the bottom sparkplug lead fitted, the motor starts first pull and idles. Same with only the middle cylinder.
But when only the top cylinder pluglead fitted, it starts immediately, run for a second or two and dies and will not start again. But put the lead back on any other piston and start and stop engine, the top cylinder will fire first time agian when connected only to die after a second or two and will not start again - even with quick start spray. Repeat procedure, and it fires again
Can anyone help me please.
Edit: Engine reconditioned after two stroke oil pump failure and the oil injection system diconnected and oil reservior/tank removed.
The symptoms are as follows; The top cylinder (closest to flywheel) refuses to fire. The engine start on first pull perfectly but immediately settle down on two cylinders only and when opening the throttle, the engine will momentarily fire on all cylinders and go like greased lightning, but then cut down to two cylinders. Closing the throttle somewhat it will sporadically fire the top cylinder for a second or so - much like turning an ignition on on off.
I suspected a fuel starvation problem but even when running on the lower two cylinders, I squirted some petrol into the carb and nothing happens, actually get worse. I fitted a new coil and it has plenty of spark but strangely, when its idling on two cylinders and I pull the top sparkplug lead off (sparks all over) and bring it towards the sparkplug and about an inch from the plug the spark would jump and the piston firing up momentarily again but stop although the spark is still jumping the distance or even when pushed onto plug. I changed sparkplugs to no avail as well as the coils with no difference. What can be at fault
I already did the following;
1. Checked compression and it fine - same across all cylinders
2. Completely stripped and cleaned the top carburator a few times already
3. Checked the coils primary and secondary - all primary ohm readings as per manual but only one coil have a secondary ohm reading as per manual - even replacement coil does not read on secondary, but that said, all have plenty of spark and changing the coil combinations makes no difference.
4. Checked the charge coil under flywheel and both resistance and voltage output within spec.
5. Gearcounter pickup resistance and output voltage within spec.
6. Pickup coils (trigger coils) all three resistance within spec (195 - 197 ohms) similar to gearcounter pickup, but the output voltage only 10% of their spec on my tester - 0.45V (spec 2.5V >) on all three pickups, compared to the gearcounter coil's 4.6V (spec 2.7V>). Even with low readings, the bottom two pistons runs pefect.
7. Changes sparkplug - hotter and colder to no avail.
8. All spark coils and pickup coils well grounded and can not find any loose connection.
Worth mentioning; with only the bottom sparkplug lead fitted, the motor starts first pull and idles. Same with only the middle cylinder.
But when only the top cylinder pluglead fitted, it starts immediately, run for a second or two and dies and will not start again. But put the lead back on any other piston and start and stop engine, the top cylinder will fire first time agian when connected only to die after a second or two and will not start again - even with quick start spray. Repeat procedure, and it fires again
Can anyone help me please.
Edit: Engine reconditioned after two stroke oil pump failure and the oil injection system diconnected and oil reservior/tank removed.
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