Tweet
DIY gone wrong!
Hi All
I helped a friend with a 2000 Yamaha 130 2 stroke, and I think we may have solved the problem.
I would just like to know if I am on the right track!
He wanted to clean out and check a sticking pressure release valve, so he took the CDI unit off its mountings to get at the PRV.
In doing so, he disconnected the coil HT wires and the low tension wires to the coils.
He fitted everything back on after checking the PRV, and on starting the motor, there was one almighty backfire from the exhaust and the motor would not start. He called me to help and I found that he had incorrectly reconnected the low tension wires for the coils. I connected the wires correctly and we started the motor.
Lots of (black), smoke, which smelt like a rich mixture. So, off with the carbs, stripped cleaned and replaced them set floats, checked fuel system lines etc.
The motor started but sounded a bit rough, so I pulled the plug leads off one at a time. There was little or no difference on the left bank (two cylinders). After checking the plugs which were almost new, I suspected that the fuel pump may be leaking into the engine block. So we stripped the fuel pump, and sure enough, one of the diaphragms had a one inch tear across it! Obviously fuel was being sucked through to the left bank cylinders!
We rebuilt the pump with a new fuel pump kit from the dealer and the motor then ran sweetly! Problem solved!
Now my question is…. Could the backfire from the incorrectly connected LT coil wires have blown a hole in the pump diaphragm?? – Just wondering!?!?
I helped a friend with a 2000 Yamaha 130 2 stroke, and I think we may have solved the problem.
I would just like to know if I am on the right track!
He wanted to clean out and check a sticking pressure release valve, so he took the CDI unit off its mountings to get at the PRV.
In doing so, he disconnected the coil HT wires and the low tension wires to the coils.
He fitted everything back on after checking the PRV, and on starting the motor, there was one almighty backfire from the exhaust and the motor would not start. He called me to help and I found that he had incorrectly reconnected the low tension wires for the coils. I connected the wires correctly and we started the motor.
Lots of (black), smoke, which smelt like a rich mixture. So, off with the carbs, stripped cleaned and replaced them set floats, checked fuel system lines etc.
The motor started but sounded a bit rough, so I pulled the plug leads off one at a time. There was little or no difference on the left bank (two cylinders). After checking the plugs which were almost new, I suspected that the fuel pump may be leaking into the engine block. So we stripped the fuel pump, and sure enough, one of the diaphragms had a one inch tear across it! Obviously fuel was being sucked through to the left bank cylinders!
We rebuilt the pump with a new fuel pump kit from the dealer and the motor then ran sweetly! Problem solved!
Now my question is…. Could the backfire from the incorrectly connected LT coil wires have blown a hole in the pump diaphragm?? – Just wondering!?!?
Comment