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Ignition Fuel Valve Wiring Problem

I've been having a few electrical issues with our 87 Newell (i.e. blinkers and defrosters apparently have a short). When I pulled the cover off the steering column to track the wires, I noticed a wire had burned through the plastic harness on the column.

There were two wires in the harness, and since I couldn't find another to replace it, I just added clips to the wires, and plugged them directly into the blades on the steering column.

However, the bus will not crank from the ignition now. It appears the wire that had burned was the ignition fuel valve wire (orange wire in the photos). When I turn the switch, the wire is hot, but the bus just turns over and sounds like it is not getting fuel now. I went to the emergency start at the back of the bus, and it fires right up. We just cannot crank from the ignition switch right now.

I tested the wire at the terminal board under the dash in front of the passenger seat, but the wire is not hot, whether the ignition switch is on or not.

I am assuming there must be a fuse in this line that blew, but I can't find a fuse and it's difficult to try to track this wire from the steering column across to the terminal board. However, I didn't have any problem cranking the bus until I reconnected the burned wire.

I was thinking of running a wire directly from the steering column blade to the terminal board (with fuse) to see if that allows the bus to crank from the ignition switch. If that works, I was just going to rerun the wire from the steering column to the terminal board. Does that sound reasonable?

Does anyone know if anything else pulls from this wire or if it is just the ignition fuel valve?

What size fuse would you recommend to put on my test wire?


Greg Lee
1987 Newell Classic Coach, 38'6"
Detroit Diesel 8V92TA, 475 HP, Allison 4-speed auto transmission, Perkins Diesel 18kw generator

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On the 77 coach I had, the wire to the fuel valve fed nothing else.

You have the typical "since-u" problem, since you fixed it it don't work Smile I don't recall there being a fuse in the line though in light of your symptoms it would make some sense. I think your plan is sensible. With nothing more to go on than SWAG I would start with a 7.5amp fuse, if that blows, go with 10. The fuel solenoid is a hefty dude, it could probably lift the back of the coach if needed. Another approach would be to measure the current at the rear switch and then install a slightly larger fuse up front.

Jon Kabbe
1993 coach 337 with Civic towed

Thanks! I'll give that a try. I just wanted confirmation from someone that i was on the right track.

     I had a short in my dash wiring that caused insulation melting on about 80% of my wiring to my gauges.  (The photo is now my screen saver.)  The short was my fault as I had just temporarily wired in a new tach and accidentally allowed wires to cross.  I ended up having to rewire all my gauges.  Anyway, there were many places that wire insulation melted in one wire and caused a short to another wire that was bundled tightly next to it.  I'm obviously no expert in this area but I wonder if your fuel valve wire melted somewhere else in that big bundle going from the dash to the terminal and when you hooked the wire up again it shorted out another wire associated with the ignition switch.  If that's the case, I would think your solution should work .  
If yours is like mine, there are no fuses or circuit breakers associated with the ignition switch wiring and the power to your headlights, gauges and fuel valve all go through the ignition switch.  So far I have placed a temporary fuse (10amp) in the main gauge power wire at the point where it comes out from the ignition switch to at least prevent another gauge wire meltdown.  I don't understand why there aren't more fuses protecting the ignition wiring but I guess it's worked for 35 yrs for this coach - until I got ahold of it!  I plan to add circuit breakers to at least a few other circuits associated with the dash that are not well protected.  It's a bit scary driving down the highway and seeing smoke billowing out from under your dash!
Good luck!

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