simplified wiring for IH 656

Hi there,

I am trying to bypass all of the non essential components of the wiring on my Diesel, "68 IH 656. The original harness is in terrible condition with corrosion and bare wires all over the place. It started ok up until a couple months ago, but then it wouldn't start and i began this project of rewiring critical components and opened up a can of worms when i found out exactly how bad the existing wiring was. So far i ran direct wires from the starter solenoid to the start button and back, i also, disconnected all the gauges, lights, etc. I then ran a direct line from the hot terminal on the starter solenoid to the glow plug warm button. However, i have gotten stuck with the ignition switch. I had thought it was supposed to be the cut off to all the other components, but it didn"t appear to be wired that way. The existing wiring seemed to have a hot wire coming into one terminal of the ignition switch, and then continuing on to the box up under the dash that i believe is a fuse box of some description (the other wires from the box go to the alternator, and there is also one going back to the hot terminal of the solenoid). The existing wire from the other terminal of the ignition switch just ended in a corroded broken piece.

So now i don"t know what to do about this ignition switch? Should i have the hot come through the switch from the solenoid, which would essentially just switch the "fuse box"? or does the hot actually come from the "fuse box" side and i should route the hot to the glow plugs and ignition through the switch?

any assistance in telling me how to rig this tractor in the most simple wiring strategy possible would be greatly appreciates...

specifically;

what is the ignition switch supposed to be switching?

what is this "fuse box" and how should it be wired in?

and, am i missing any other critical components that i shouldn"t have bypassed?

thanks so much

Gwen

Your operators manual should be your first source for info. Good wiring diagram in it.

Now as to some of your questions,

There is no "fuse box" only a single fuse holder that feeds the light switch.

The key switch feeds the fuel gauge, start switch button, and if you have them the alternator excite terminal and the air restriction indicator.

The glow plugs are wired from the starter solenoid to the glow plug push button and then to the glow plug junction block on the cyl head.

There is also a clutch safety switch and I am not going to tell you how to bypass it.
HTH

Thanks for the info, I guess i need the operator's manual. I have the Shop Manual and it is remarkably unhelpful.

I think from what you are saying this tractor has had some major bypassing done on it before... including the clutch safety switch because i haven't seen anything functional of that description.

Gwen