well here i am. after years of reading other peoples threads and being able to figure out my problems ive decided to finally join the forums for myself. thanks you everyone for the useful info thus far.
brief history of the problem.
new to me 1998 yamaha 250 ox66. mounted the outboard to my boat and couldn't hit wot. i figured fuel issues. i cleaned vst and changed all the filters i didnt change the lp pumps as the previous owner just replaced them and the primer ball gets firm this all helped but didn't fix my problem.
changed plugs, cleaned o2 sensor and bench tested, checked tps, the new plugs showed me i wasn't firing on the number 2 cylinder under compression because i had spark while testing with a spark light. i ohmed coils, and replaced plug boots. compression test showed good, switched injectors and problem stayed in number 2. i swapped out pulsar coil, stator and crank position sensor with a known good spare i already had.
now for the tricky part. so i go out to test and see what my wot is going to be and it still have a dead cylinder. i hit the trim up switch and the motor starts to fire on all cylinders and takes off. every time it would bog down and i would hit the trim up switch it would pick back up. i get back to the dock thinking i have a short or some kind of electrical gremlin jumping around inside the cowling. once at the dock i noticed that the blue and green trim motor wires are all melted and junk. i tested the motor side wires and relay seems to be working, but what i did notice was the black bullet connector on the motor side was producing 3.5 volts while the trim motor had continuity to bullet connector and black wire with the ring terminal. that doesn't sound right. any help would be appreciated.
brief history of the problem.
new to me 1998 yamaha 250 ox66. mounted the outboard to my boat and couldn't hit wot. i figured fuel issues. i cleaned vst and changed all the filters i didnt change the lp pumps as the previous owner just replaced them and the primer ball gets firm this all helped but didn't fix my problem.
changed plugs, cleaned o2 sensor and bench tested, checked tps, the new plugs showed me i wasn't firing on the number 2 cylinder under compression because i had spark while testing with a spark light. i ohmed coils, and replaced plug boots. compression test showed good, switched injectors and problem stayed in number 2. i swapped out pulsar coil, stator and crank position sensor with a known good spare i already had.
now for the tricky part. so i go out to test and see what my wot is going to be and it still have a dead cylinder. i hit the trim up switch and the motor starts to fire on all cylinders and takes off. every time it would bog down and i would hit the trim up switch it would pick back up. i get back to the dock thinking i have a short or some kind of electrical gremlin jumping around inside the cowling. once at the dock i noticed that the blue and green trim motor wires are all melted and junk. i tested the motor side wires and relay seems to be working, but what i did notice was the black bullet connector on the motor side was producing 3.5 volts while the trim motor had continuity to bullet connector and black wire with the ring terminal. that doesn't sound right. any help would be appreciated.