Last fall the motor would not start up every now and again… Then the motor trim up would not work some times… so either they were separate issues or they were related.
First things first, after calling a Yamaha expert I changed the trim switch on the throttle shifter. I also swapped the fuel filter and cleaned off the water sensor in the bowl located on the front of the motor.
After reinstalling everything the trim up was still hit and miss… so it was definitely a wiring issue and not a switch.
Problem is that the issue with the trim was intermittent and so the wires tested good then another check showed that the wire was broken. Good then not good…. gerrrr I hate it when that happens. Means that a wire connection is just barely touching and any movement would trigger the separation. I had this on a Hercules C130 back in a previous life and it took days to find that one wire.
Fortunately this only took a few hours to find. By the looks of the wiring inside the wiring harness extension (the harness extension that goes from the motor to the bilge where it attached to the harness that goes to the dash) there are a lot of issues that were ready to create problems.
The top picture has a cut out section of the blue up trim wire. The cut out section is where te wires are broken.
Doesn’t take much to wreak havoc