Is there a internet source for the electrical schematic of an International Harvester Farmall 706 diesel, abou 1965?

Your number does not seem to match what I could find. Please check the serial number plate on the left side of the 706 clutch housing, driver side.
1963: 501
1964: 7073
1965: 21162
1966: 30288
1967: 38521
Final: 46647

Hope this helps.

http://www.tractordata.com/farm-tractors/004/6/6/4669-farmall-706.html

I don't know where there's a schematic on the web, however, the schematic is in this shop manual:
SMIH203 International Harvester Farmall Shop Manual

Good luck

http://binatani.com/wp-content/uploads/2011/08/International-Harvester-Farmall-M-alternator-conversion-schematic.jpg

cranks ok , and fast?
after checking all fuses. (the FSM shows correct fuse)

International Harvester IDI (from Indirect Injection) engine is a 4-stroke 8-cylinder Diesel engine used in International Harvester trucks,
like all diesels check fuel filters first. (service)
then make sure glow plugs work. (fsm covers this)
then scan it EFI for DTC errors. got errors?
direct injection uses EFI.

IF DIY, you need the book, I promise.....
its not simple like old diesels were.

check under and around the seat

bad rings on pistons

I just found one www.waltstractors.com

look just bihind the oil filer base . there should be engine size stamped on flat surface

You should be able to pull the whole distributor out by taking one bolt out that holds a Y bracket on that holds the distributor down. Make sure you mark the distributor and the engine before you pull it out. Also mark the rotor. Once you get it out, you will be able to determine if the shaft is broken. Hold the gear and try to spin the rotor. If the shaft is broken, you will probably need a new distributor. Seems strange that the shaft would bust, but I guess anything is possible.

look for a tank reservoir with a dipstick. Locate the pump or cylinder and follow the line back to the tank.