I am new to the forum, as well as, boating, so thanks to everyone in advance for your patience and help.
I recently purchased a used 2000 Beachcomber pontoon with a 2000 (12/1999) Johnson 70hp outboard (J70PLSS). I had the motor inspected and compression tested by a mechanic and all checked out well. A major tune-up was done that entailed a carb rebuild, new VRO pump, and spark plugs.
The first time I ran the boat there were no issues, ran like it was brand new. From that time on (about 6 times) the motor has started acting up on me in that the motor starts to stutter, bang\knock and shakes the boat. The prop essentially stops spinning with enough force to propel the boat. Some times it will do this for a couple of minutes and then start running fine for the rest of the day, sometimes it will run fine and then start doing this no stop. Occasionally it will do this the entire trip. It will do it sometimes immediately on start up, sometimes it will run fine all day and start to do it when I am going back to the house. So really no rhyme or reason. When it does this it will do it at idle and when in gear, with the exception of getting the motor to 1000 rpm. I can hit and stay at 1000 rpm and the motor will run like there are no issues. If I throttle too high the motor will choke out and quit. Also tried pushing the choke when this starts to happen and it chokes the motor out. It is almost like the overheat mode is kicking in, however, the pump is pumping a good stream that is not hot. Also this will happen immediately on start up so the motor shouldn't be too hot then.
I brought the boat back home and had the mechanic's recheck the boat after it did this to me 2 or 3 times, of course they took it out on a lake run twice and the boat worked fine for them each time. So I hate to have to pull it home again for it to do the same thing once I take it to the mechanic and I am starting to run out of money for them to continue doing work. At this point they suggested that the primer solenoid be replaced, which I did. I took it back to the lake and it ran ok the first time and low and behold it started doing the same thing to me the next 2 times I ran it. This also occurs on the hose.
Things I have done:
1. Confirmed that the VRO is pumping gas by unclipping it from the motor and gas pumps out of the line.
2. Emptied the gas tank twice, the best I could, and put fresh gas in, even filled it with Premium once. The tank was syphoned before I ever ran the motor on it.
3. Checked the Carb bulbs to make sure they were not filled with junk.
4. The fuel bulb gets tight when pumped.
Things I think could be the problem based on others from this forum:
1. Bad fuel line, bulb, or connection. I currently have the goodyear line not the gray aftermarket.
2. Potential bad temp sensor causing the Overheat mode to kick in randomly.
3. Bad powerpack.
4. ??????
My boat is at the lake about 2.5 hours from me, with no mechanic at the lake, so I am trying to identify the potential problems so that I can try to run through them all the next time I head back to the lake. Any suggestions and help on how to diagnose would be appreciated.
Thanks.
I recently purchased a used 2000 Beachcomber pontoon with a 2000 (12/1999) Johnson 70hp outboard (J70PLSS). I had the motor inspected and compression tested by a mechanic and all checked out well. A major tune-up was done that entailed a carb rebuild, new VRO pump, and spark plugs.
The first time I ran the boat there were no issues, ran like it was brand new. From that time on (about 6 times) the motor has started acting up on me in that the motor starts to stutter, bang\knock and shakes the boat. The prop essentially stops spinning with enough force to propel the boat. Some times it will do this for a couple of minutes and then start running fine for the rest of the day, sometimes it will run fine and then start doing this no stop. Occasionally it will do this the entire trip. It will do it sometimes immediately on start up, sometimes it will run fine all day and start to do it when I am going back to the house. So really no rhyme or reason. When it does this it will do it at idle and when in gear, with the exception of getting the motor to 1000 rpm. I can hit and stay at 1000 rpm and the motor will run like there are no issues. If I throttle too high the motor will choke out and quit. Also tried pushing the choke when this starts to happen and it chokes the motor out. It is almost like the overheat mode is kicking in, however, the pump is pumping a good stream that is not hot. Also this will happen immediately on start up so the motor shouldn't be too hot then.
I brought the boat back home and had the mechanic's recheck the boat after it did this to me 2 or 3 times, of course they took it out on a lake run twice and the boat worked fine for them each time. So I hate to have to pull it home again for it to do the same thing once I take it to the mechanic and I am starting to run out of money for them to continue doing work. At this point they suggested that the primer solenoid be replaced, which I did. I took it back to the lake and it ran ok the first time and low and behold it started doing the same thing to me the next 2 times I ran it. This also occurs on the hose.
Things I have done:
1. Confirmed that the VRO is pumping gas by unclipping it from the motor and gas pumps out of the line.
2. Emptied the gas tank twice, the best I could, and put fresh gas in, even filled it with Premium once. The tank was syphoned before I ever ran the motor on it.
3. Checked the Carb bulbs to make sure they were not filled with junk.
4. The fuel bulb gets tight when pumped.
Things I think could be the problem based on others from this forum:
1. Bad fuel line, bulb, or connection. I currently have the goodyear line not the gray aftermarket.
2. Potential bad temp sensor causing the Overheat mode to kick in randomly.
3. Bad powerpack.
4. ??????
My boat is at the lake about 2.5 hours from me, with no mechanic at the lake, so I am trying to identify the potential problems so that I can try to run through them all the next time I head back to the lake. Any suggestions and help on how to diagnose would be appreciated.
Thanks.