At the beginning oif the summer, the engine ran just fine. I could do 32 mph over flat water. Then one morning after trolling for 3 or 4 hours the engine backfired when I opened it up, leaving a slick of dry "exhaust" on the lake surface. Then the boat would only max out at 24 mph. Tried changing plugs, wires, etc with no luck. The plugs would be fouled with carbon, especially on cyllinder 3. We changed the plugs a total of 3 times, including once with hotter burning plugs.<br /><br />The last trip out, after trolling for a couple hours, the engine began running sluggishly while trolling. When I opened it up to head back to shore, it again backfired. This time after backfiring, the best speed I could acheive was 7mph, and that was only when I could keep it from stalling.<br /><br />Today I ran a compression test on all 4 cyllinders and got these results:<br />140<br />140<br />145<br />128<br /><br />Does anyone have an similar experiences and/or have any thoughts or suggestions?
