90 HP carbed Johnson 2-stroke: starts right up and runs fine at idle and 5 mph. Most of the time it runs fine up to about 5400 rpm with plenty of power.
Sometimes, though, when cruising at, say, 3500 rpm the engine will bog (without me touching the throttle), lose power and slow down. Then after some seconds it revs back up again with full power. Also sometimes when running normally and I gun the throttle it will bog, refuse to go over 4000-4500 rpm, no response from the throttle. Then later after slowing down it responds to throttle normally.
I pushed in the choke when it bogged and it stalled. The ball was full when I squeezed it. Am going to check water/fuel separator, compression and condition of plugs, but I expect all this to be normal as it runs fine most of the time. Just decarbed with Sea Foam without effect.
Am thinking it could be an electrical problem with a component starting to fail after it heats up. Maybe 2 of 4 cylinders aren't firing when it bogs?
Anyone have any thoughts on what to check?
Sometimes, though, when cruising at, say, 3500 rpm the engine will bog (without me touching the throttle), lose power and slow down. Then after some seconds it revs back up again with full power. Also sometimes when running normally and I gun the throttle it will bog, refuse to go over 4000-4500 rpm, no response from the throttle. Then later after slowing down it responds to throttle normally.
I pushed in the choke when it bogged and it stalled. The ball was full when I squeezed it. Am going to check water/fuel separator, compression and condition of plugs, but I expect all this to be normal as it runs fine most of the time. Just decarbed with Sea Foam without effect.
Am thinking it could be an electrical problem with a component starting to fail after it heats up. Maybe 2 of 4 cylinders aren't firing when it bogs?
Anyone have any thoughts on what to check?
