SuperEnzo
Seaman Apprentice
- Joined
- Dec 11, 2014
- Messages
- 32
Hi guys, Im the new owner of a 1971 sears 14 foot aluminum rowboat that came with a 1977 mercury 7.5hp outboard serial number 4692832!
The motor fired right up after new plugs, a carb clean, and a new impeller and a general inspection. However the ignition system had some sort of rtf all over the switch box wires. upon pealing this all back I found that the wires beneath were corroded and were not in condition to my liking. So Its not possible to solder into corroded wire so naturally i kept going stripping more and more wire to try and find shiny clean wire and none was to be found until i finally was out of wire and I was back to the switch box. Here is the switch box (ignore the blue piece of painters tape)
the switch box is covered in black silicone rubber and so I started to remove it with a utility knife and a few flat head screw drivers- heating the silicone up periodically to keep it somewhat soft. I was able to remove all of the silicone rubber (painstakingly slow mind you) in a total of about 4 hours Id say. There is one circuit board inside and 2 large capacitors as you can see
the circuit board lays on top of the 2 capacitors like so
I will now proceed to replace all of the wires and make this switch box like new.
One question I do have is if anyone has done this before and has experience with mercury part numbers and such can anyone tell me the specs on the capacitors? Like voltage rating and capacitance? The capacitors I have do in fact work however the leads to the capacitors snapped off and while I can resolver a leg on I would rather not. If not then ill just re-solder a leg on.
I hope that this helps anyone trying to fix their thunderbolt ignitions and not spend an arm and a leg trying to replace them
PS if anyone needs detailed pictures of the circuit I can take some
-Ethan
The motor fired right up after new plugs, a carb clean, and a new impeller and a general inspection. However the ignition system had some sort of rtf all over the switch box wires. upon pealing this all back I found that the wires beneath were corroded and were not in condition to my liking. So Its not possible to solder into corroded wire so naturally i kept going stripping more and more wire to try and find shiny clean wire and none was to be found until i finally was out of wire and I was back to the switch box. Here is the switch box (ignore the blue piece of painters tape)
the switch box is covered in black silicone rubber and so I started to remove it with a utility knife and a few flat head screw drivers- heating the silicone up periodically to keep it somewhat soft. I was able to remove all of the silicone rubber (painstakingly slow mind you) in a total of about 4 hours Id say. There is one circuit board inside and 2 large capacitors as you can see
the circuit board lays on top of the 2 capacitors like so
I will now proceed to replace all of the wires and make this switch box like new.
One question I do have is if anyone has done this before and has experience with mercury part numbers and such can anyone tell me the specs on the capacitors? Like voltage rating and capacitance? The capacitors I have do in fact work however the leads to the capacitors snapped off and while I can resolver a leg on I would rather not. If not then ill just re-solder a leg on.
I hope that this helps anyone trying to fix their thunderbolt ignitions and not spend an arm and a leg trying to replace them
PS if anyone needs detailed pictures of the circuit I can take some
-Ethan