Guys, I need your help. I don't know motors at all, so I really need help in assisting my mechanic on what is wrong. I have taken it to him twice, and the problem remains. I know his skill, so I think it is because I can't lead him to the problem or even explain it well.
I bought this motor used along with a pontoon boat. The motor had few hours (20-40 was both guesses) per the inspecting mechanic and confirmed by my own mechanic. It appeared to have never been serviced and still had the plugs, water pump, etc. from the factory. The compression readings are great, but the third carb was gunked up. Everything else seemed fine on it. I had them replace the water pump, plugs, gasket sets, clean out and rebuild the carbs and replace the inlet needles, dump the gas and change the gear oil.
We took it out, and it started great, idled great, accelerated smoothly and overall performed well for the first cruise out from the ramp. We cruised for a little while and had no issues. After sitting still for a while for my kids to swim, we started it up again. This time, it never could get to full power. It would sputter some but max out at 3,000 RPMs and sort of flood from time to time dropping to 2800 RPM's at this less than max power. When I say less than max power, I had the throttle at full, but the engine couldn't get there.
Took it to him, and he checked that the control box was getting the motor to full throttle when all the way forward. It was. I left it with him, and he said he couldn't find anything wrong but put a new tacometer on in case it was just a bad tac read.
I took it back to the lake, and I had the exact same experience. This time, it ran perfect for an hour or so of cruising. Anchored up and swam for an hour and a half, and then started our cruise back. The only thing I changed during this time was I topped off the oil in the engine. It didn't need oil, but I just topped it off while we were sitting there. (Can you put too much oil in an oil injection motor? Serious question.)
After restart, it did it again. It would sputter and struggle and could not acheive maximum power. I checked fuel tank vent, gas line attached, oil level obviously fine, fuel level fine, fuel bulb appeared full of fuel, but it was flooding out or something and not getting to maximum power. Once again, 3,000 RPM's and less than maximum power was what I was getting at wide open.
I decided to try something and started the engine like it was flooded. Opened the idle all the way up and fired it up quickly backing the idle down. This improved it, but only slightly. Now, I could get to 4,000 RPM's and slightly more power, but it was not performing at peak performance like it did on the way out. By the way, we cruised out at about 4,800 RPM's, throttled all the way would get me to 5,000, and the engine is capable of 5,500.
I trust my mechanic and suspect that when he fires it up, he is getting good performance just as I have the first two times out at the beginning. I hate to take it back to him with no more guidance than what I describe above.
Does anyone have any ideas on what could be happening? Don't hesitate to tell me it is user error. I can take it.
P.S. I have tried running the motor at all levels of trim. It has no effect on the performance issues described above.
I bought this motor used along with a pontoon boat. The motor had few hours (20-40 was both guesses) per the inspecting mechanic and confirmed by my own mechanic. It appeared to have never been serviced and still had the plugs, water pump, etc. from the factory. The compression readings are great, but the third carb was gunked up. Everything else seemed fine on it. I had them replace the water pump, plugs, gasket sets, clean out and rebuild the carbs and replace the inlet needles, dump the gas and change the gear oil.
We took it out, and it started great, idled great, accelerated smoothly and overall performed well for the first cruise out from the ramp. We cruised for a little while and had no issues. After sitting still for a while for my kids to swim, we started it up again. This time, it never could get to full power. It would sputter some but max out at 3,000 RPMs and sort of flood from time to time dropping to 2800 RPM's at this less than max power. When I say less than max power, I had the throttle at full, but the engine couldn't get there.
Took it to him, and he checked that the control box was getting the motor to full throttle when all the way forward. It was. I left it with him, and he said he couldn't find anything wrong but put a new tacometer on in case it was just a bad tac read.
I took it back to the lake, and I had the exact same experience. This time, it ran perfect for an hour or so of cruising. Anchored up and swam for an hour and a half, and then started our cruise back. The only thing I changed during this time was I topped off the oil in the engine. It didn't need oil, but I just topped it off while we were sitting there. (Can you put too much oil in an oil injection motor? Serious question.)
After restart, it did it again. It would sputter and struggle and could not acheive maximum power. I checked fuel tank vent, gas line attached, oil level obviously fine, fuel level fine, fuel bulb appeared full of fuel, but it was flooding out or something and not getting to maximum power. Once again, 3,000 RPM's and less than maximum power was what I was getting at wide open.
I decided to try something and started the engine like it was flooded. Opened the idle all the way up and fired it up quickly backing the idle down. This improved it, but only slightly. Now, I could get to 4,000 RPM's and slightly more power, but it was not performing at peak performance like it did on the way out. By the way, we cruised out at about 4,800 RPM's, throttled all the way would get me to 5,000, and the engine is capable of 5,500.
I trust my mechanic and suspect that when he fires it up, he is getting good performance just as I have the first two times out at the beginning. I hate to take it back to him with no more guidance than what I describe above.
Does anyone have any ideas on what could be happening? Don't hesitate to tell me it is user error. I can take it.
P.S. I have tried running the motor at all levels of trim. It has no effect on the performance issues described above.