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Discussion Starter · #1 · (Edited)
I bought a 86 fourtrax ive been trying to get running, had a bad relay when I got it and some shorted, chewed, and horribly re wired connections (literally just twists and tape) I bought a New fuel cut off relay for it and repaired all the wiring with solder, dielectric grease and shrink wrap, and before doing those repairs I confirmed every wire was in place, but now I’ve lost spark, the fan control unit is making noises, and there’s one wire that’s giving me confusion, it’s a green and white wire that’s meant to go to the alt from the CDI but both of those are crimped into the ground? Is that normal? The only reason it’s confusing me is because it looks like it’s just the ground for the alt but I’m not sure, Here’s pictures of what I’m talking about aswell as a video of the FCU noise.
152253

 

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Discussion Starter · #4 ·
for spark, I asked before, did you do the oven trick for the CDI?
What is the oven trick?? And for the white green is it okay as Is? Or should they be seperated from that ground wire? And is the fan control unit supposed to make that noise or is it shorting out? The oil light doesn’t come on either and it’s wired to that
 

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I see what you are saying regarding the white/green wire.
that does seem wrong, as all greens are "comm" and one green goes to the spark plug coil. so that could be your issue if you are grounding the coil.

It may be a PITA, but I would follow the schematics and pull out all the green wires, making sure they all go to where they are supposed to and only then, remove that green/white and route the green/white the way it should be.

Oven trick

the noise does not sound right to me.
 

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Discussion Starter · #6 ·
I see what you are saying regarding the white/green wire.
that does seem wrong, as all greens are "comm" and one green goes to the spark plug coil. so that could be your issue if you are grounding the coil.

It may be a PITA, but I would follow the schematics and pull out all the green wires, making sure they all go to where they are supposed to and only then, remove that green/white and route the green/white the way it should be.

Oven trick

the noise does not sound right to me.
Could the fan control unit be the reason I’m getting no spark? Or is it completely un related? The CDI appears to be in great shape
 

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you can try following page 17-3
no spark...
replace spark plug with new
no spark
check spark plug wire for loose connection at the cap, try again
no spark
check cdi connections
all good?
check related components
pulse generator
ignition coil
ignition switch
engine stop switch
ground wire (Green/white)

the wiring diagram is very simple just gotta follow wire by wire or continuity check across from and to all connectors

From the coil, you got two wires
1. Black/yellow goes to fuel pump relay and cdi
2. Green wire, green wire goes almost everywhere and ground
 

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Discussion Starter · #11 · (Edited)
Perform the overheat diagnostics
As I mentioned your oil light must come on momentarily and then go out—that is the first strp
It doesn’t come on at all, just sparking sounds from the FCU when I hit the key, is there a bypass I can do? It doesn’t even have a fan installed
 

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Discussion Starter · #14 ·
The neutral light comes on when I turn the key just not the oil temp light, for the brief second that the light is supposed to come on is when I’m experiencing the sparking sounds from the fcu, I’ve ordered a new one aswell as a CDI, and ignition coil for the no spark, just waiting on parts now (cost 500$ for all oem) fingers crossed or I’m rolling it to the dump
 

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I hope that all works for you.
if not, these things can pay you back by parting them out.

go over to atvhonda.com and see if those members can be of more help
 
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