Alright, I've been browsing these forums for a quite a while and, thanks to the experiences and advice of the members here, have successfully diagnosed and fixed a few of my prior outboard problems, but am finally in a spot where I believe a post is required.
The motor is a older Tohatsu m50c 2 stroke on a 16 ft StarCraft, both of which were just purchased. Considering the price, I was somewhat expecting some work to be needed, even though it test-ran decent when purchasing. I have, in the past few weeks, replaced the water pump impeller and housing, fixed the shift linkage to the lower unit, reversed the steering, fixed the tilt and trim (temporarily), new plugs, and completely took apart and cleaned out both carbs.
This last time I took it out on the water (prior to carb cleaning) was the first time I had really opened up the throttle after the initial repairs I did. It idled fairly rough, cruised at low speeds for about 10 minutes, and when I gave it some gas it got up on plane GREAT and pushed the boat even faster than expected. Ran full speed for about 3-4 minutes flawlessly then started to bog down really bad, eventually dying. Seemed like it was flooded and could see gas running out if I pumped the ball. Pulled it back to the ramp (2 miles on foot via sandbar lol), where it then started (slowly) once we were back, of course. got home and hooked it up to the muffs to flush it. It started, allowing me to flush it, but the starter turned over rather slowly. Now my diagnosis for both problems: considering the performance, the fuel leaking out the carb when ball squeezed, and the fact that boat sat for about 6 months, I figured the carb was super dirty and gunked up causing the bogging/flooding. As for the two weak starts, I was just assuming I had ran down the battery while trying to crank it so long while on the water in conjunction with the lights/electronics.
I removed and broke down both carbs, saw that everything was extremely dirty and gunked up as expected, used a full 2 cans of carb cleaner on every part and hole, dried with compressed air, then reassembled everything.
Tried to start it with the muffs on to no avail. starter turned flywheel very slowly (1 turn every second or two) but not enough to actually get it going. Still thinking the battery is just dead, I hooked it up to the charger for a few hours, came back and got same thing when trying to crank it. Went through and checked the wiring and connection points pretty thoroughly. cleaned and cinched down a couple spots a bit but everything seemed to be pretty clean and tight, with no visible corrosion or hot spots. Same slow turn. Unhooked the battery and, after disconnecting the wires from the starter, hooked up the battery directly to the starter post with jumper cables. Still turned slowly. Took the battery from my truck, which I know is good, and again jumped it directly to the starter. Once again, it turned slowly.
Now I believe I have isolated the problem to be the starter motor. I am by no means an expert mechanic, but considering the slow turns when jumped directly from my truck battery, I just don't see how it could possibly be anything else such as the solenoid or wiring.
Would like some more experienced guys to chime in before I just pay for a rebuild/new starter. Any input would be greatly appreciated!
The motor is a older Tohatsu m50c 2 stroke on a 16 ft StarCraft, both of which were just purchased. Considering the price, I was somewhat expecting some work to be needed, even though it test-ran decent when purchasing. I have, in the past few weeks, replaced the water pump impeller and housing, fixed the shift linkage to the lower unit, reversed the steering, fixed the tilt and trim (temporarily), new plugs, and completely took apart and cleaned out both carbs.
This last time I took it out on the water (prior to carb cleaning) was the first time I had really opened up the throttle after the initial repairs I did. It idled fairly rough, cruised at low speeds for about 10 minutes, and when I gave it some gas it got up on plane GREAT and pushed the boat even faster than expected. Ran full speed for about 3-4 minutes flawlessly then started to bog down really bad, eventually dying. Seemed like it was flooded and could see gas running out if I pumped the ball. Pulled it back to the ramp (2 miles on foot via sandbar lol), where it then started (slowly) once we were back, of course. got home and hooked it up to the muffs to flush it. It started, allowing me to flush it, but the starter turned over rather slowly. Now my diagnosis for both problems: considering the performance, the fuel leaking out the carb when ball squeezed, and the fact that boat sat for about 6 months, I figured the carb was super dirty and gunked up causing the bogging/flooding. As for the two weak starts, I was just assuming I had ran down the battery while trying to crank it so long while on the water in conjunction with the lights/electronics.
I removed and broke down both carbs, saw that everything was extremely dirty and gunked up as expected, used a full 2 cans of carb cleaner on every part and hole, dried with compressed air, then reassembled everything.
Tried to start it with the muffs on to no avail. starter turned flywheel very slowly (1 turn every second or two) but not enough to actually get it going. Still thinking the battery is just dead, I hooked it up to the charger for a few hours, came back and got same thing when trying to crank it. Went through and checked the wiring and connection points pretty thoroughly. cleaned and cinched down a couple spots a bit but everything seemed to be pretty clean and tight, with no visible corrosion or hot spots. Same slow turn. Unhooked the battery and, after disconnecting the wires from the starter, hooked up the battery directly to the starter post with jumper cables. Still turned slowly. Took the battery from my truck, which I know is good, and again jumped it directly to the starter. Once again, it turned slowly.
Now I believe I have isolated the problem to be the starter motor. I am by no means an expert mechanic, but considering the slow turns when jumped directly from my truck battery, I just don't see how it could possibly be anything else such as the solenoid or wiring.
Would like some more experienced guys to chime in before I just pay for a rebuild/new starter. Any input would be greatly appreciated!
