I have recently rebuilt the GM 181 (3.0ltr) 135 hp engine in my '07 Larson 180 Sport, after spinning a rod bearing. I put the engine back in and got her running with no problem. I took her out for a sea trial and she ran great at various RPM's for the first hour, then things happened. No, the engine is fine, this time it is electrical.
We were on a moderate plane when the engine just quit. It almost sounded like the drive locked up first, then the engine died. i didn't hit anything and I didn't hear any loud noises, it just sounded like the drive stopped abruptly, causing the engine to die. When I tried to start the engine again, the ign was dead. The other accessories that were not controlled by the ign were operationa, but nothing to the engine. I found a blown 20 amp fuse in line with the thick red hot wire going to the ign switch. I replaced it with a 15 amp, which blew as soon as I tried to turn over the engine. I then took a small pair of pliers and closed the circut. I turned the engine over, but it didn't start. It sounded like it had spark because it sputtered once or twice, but no start. I then rigged it with a bent nail, closing the circut. This allowed the engine to start right up. This was approx 10-15 minutes after the engine initially died. I was able to run for about 1-2 minutes before the engine died when the nail fell out of the fuse holder. After replacing the HOT nail (coincidentally, the wires were not hot, just a bit warm), I was able to get her started again. I ran for another 1-2 minutes and it died in the channel toward the ramp. I was not able to get her started again. Each time she died, it soulded exactly the same. Prop locked up, then engine quit.
I loaded her as the sun was falling then made it home to a wife and 7 day old who wanted my attn. I was lucky enough to be able to go out, leaving my wife and new born, so I didn't do anything except rinse her down and try to start her once on the hose with no signs of spark.
This morning, I woke up for work and it hit me. When I pulled the drive, I accidentally separated the drive shaft from the lower unit, exposing the gears and leaking approx 1/2 pint of gear oil. No, I never replaced the gear oil.
My Theory:
Low oil from my spilling and possibly a current leak, which resulted in what happens when metal has no oil to lube it, friction/heat. I believe that there is a sensor that "senses" impending doom or catastrophic failure of the lower unit in the event of high heat situations. This in then sent extra current to the hot wire which blew the ign fuse. The engine started up the first time because it had enough time to cool. The second start is a mystery that probably disproves my theory. It wouldn't start the third time because of too much heat, or another blown fuse somewhere else.
There is one pigtail that contains 3 wires that goes through the transom to the outdrive. I don't know what they do, for they are not the tilt/trim wires, much thinner. I believe one is a sensor, one is power and the other is a mystery.
What do these wires do?
Why is it blowing fuses w/o even sounding a warning first?
Have I lunched my lower unit?
I am working a 24 hr shift as a firefighter paramedic, but when I get home tomorrow, I will first check my lower unit oil level. It may have leaked or taken on water due to me compromising the seal. I will then fill it or tear it apart if milkey. If just low, I will try to start engine. If no ign, I will check for spark. If no spark, I will look for another fuse.
I know this is a long post, but I believe I have completely painted the picture. Please help, this boat has been a nightmare for over a year. I just want to be able to enjoy it on my upcomming vacation, next week.
Thanks,
Mike
We were on a moderate plane when the engine just quit. It almost sounded like the drive locked up first, then the engine died. i didn't hit anything and I didn't hear any loud noises, it just sounded like the drive stopped abruptly, causing the engine to die. When I tried to start the engine again, the ign was dead. The other accessories that were not controlled by the ign were operationa, but nothing to the engine. I found a blown 20 amp fuse in line with the thick red hot wire going to the ign switch. I replaced it with a 15 amp, which blew as soon as I tried to turn over the engine. I then took a small pair of pliers and closed the circut. I turned the engine over, but it didn't start. It sounded like it had spark because it sputtered once or twice, but no start. I then rigged it with a bent nail, closing the circut. This allowed the engine to start right up. This was approx 10-15 minutes after the engine initially died. I was able to run for about 1-2 minutes before the engine died when the nail fell out of the fuse holder. After replacing the HOT nail (coincidentally, the wires were not hot, just a bit warm), I was able to get her started again. I ran for another 1-2 minutes and it died in the channel toward the ramp. I was not able to get her started again. Each time she died, it soulded exactly the same. Prop locked up, then engine quit.
I loaded her as the sun was falling then made it home to a wife and 7 day old who wanted my attn. I was lucky enough to be able to go out, leaving my wife and new born, so I didn't do anything except rinse her down and try to start her once on the hose with no signs of spark.
This morning, I woke up for work and it hit me. When I pulled the drive, I accidentally separated the drive shaft from the lower unit, exposing the gears and leaking approx 1/2 pint of gear oil. No, I never replaced the gear oil.
My Theory:
Low oil from my spilling and possibly a current leak, which resulted in what happens when metal has no oil to lube it, friction/heat. I believe that there is a sensor that "senses" impending doom or catastrophic failure of the lower unit in the event of high heat situations. This in then sent extra current to the hot wire which blew the ign fuse. The engine started up the first time because it had enough time to cool. The second start is a mystery that probably disproves my theory. It wouldn't start the third time because of too much heat, or another blown fuse somewhere else.
There is one pigtail that contains 3 wires that goes through the transom to the outdrive. I don't know what they do, for they are not the tilt/trim wires, much thinner. I believe one is a sensor, one is power and the other is a mystery.
What do these wires do?
Why is it blowing fuses w/o even sounding a warning first?
Have I lunched my lower unit?
I am working a 24 hr shift as a firefighter paramedic, but when I get home tomorrow, I will first check my lower unit oil level. It may have leaked or taken on water due to me compromising the seal. I will then fill it or tear it apart if milkey. If just low, I will try to start engine. If no ign, I will check for spark. If no spark, I will look for another fuse.
I know this is a long post, but I believe I have completely painted the picture. Please help, this boat has been a nightmare for over a year. I just want to be able to enjoy it on my upcomming vacation, next week.
Thanks,
Mike