I have a 1990 f 250 7.3 idi an it's been hard starting lately an I drove home from work parked it smelt burning wires but couldn't see any smoke got up next to go to work an it wouldn't start at all won't even hit an wait to start light doesn't come on now either

 

Any power to lights, fan etc?


If I had to guess I would say a cable or fusible link coming off the battery burnt up. Make sure you check for shorts or replacing the burnt wire will just result in the same thing happening.


Probably not a bad idea to keep a fire extinguisher close by.

 

I have power at lights an all that it turns over but won't start only thing different is the wait to start light don't come on

 

Have a close look at your wiring harness on the passenger side fender/inner fender. Look at where the wires go into the large black connector, and make sure nothing looks rough, or burnt before/after the connector. Fuse links will usually be out of the plastic loom and by themselves. I had one of the two fuse links outside the loom going to the connector break on me, and bring things to a quick halt with no power like you are describing.

Have a gander in the manual for size/description of fuse links too

 

^^^yup, check that connector on the fender. The two yellow wires I believe are the culprits. They get hot. Happend to me. Just pull them out and connect them outside that junk plastic connector.
Probably looks like this fire hazzard right here

 

Those two yellow wires are what powers the glow plug system. I put them in a separate heavy duty connector. Then check the connections on rest of those connectors that multi-plug. Sounds like you may not be getting power to the fuel solenoid in the iP.
http://www.batterymart.com/merchant2...b50-yellow.jpg

 

My yellow wires went bad a long time ago too. Seems to be typical on these old beasts. I bypassed the engine connector with two yellow wires and butt splices. Use some decent stuff, it draws a lot of current.

 

ok guys I checked all that I don't have power going to fuel cut off I jump wire from there to pos on battery an it clicked an started right up but I don't know where that wire leads somewheres to back of block I'm guessing

 

I also have power going to the glow plug relay nothing coming out

 

I would check all your fuses. Then check the ignition switch on the steering column under the dash.

 

In the picture above that Jarkill posted (nice pic btw), there are those two dark blue/almost grey wires going out of view on the left side of the connector in the pic; they are out of the loom and go in to the connector one above the other second from right side of it when looking over the passenger fender. Disconnect the connector, turn key on, and take a test light and probe those two pins. IIRC, both should have constant power w/key on.

In the manual, those are 20 gauge fuse links that power "Diesel Engine". Those send power (or at least one does for sure) to WTS light and FSS; doesn't hurt to check if you haven't already and eliminate simple things first

Idk how to post or edit pics, sorry to be long winded!

 

Same problem on my 88. Temp fix for now. 6 feet of 10 gauge to 14 gauge fusible straight to gpm.