Hi all.I have noticed that the wiring diagram in my original Ferguson TE 20 shop manual has a peculiar way of wiring the ammeter. The same diagram is also found on the FOFH website, and also on the American Ferguson club. I have looked at the wiring diagram for the MF 35 and 65 (UK built) and they are different. But, there is a note on the MF 65 wiring diagram that says it has been converted from the way the TE 20 diagram is to the new way. The difference is that if anyone wires a tractor according to the TE 20 diagram the ammeter which is a normal - and + ammeter will show only charging, and not discharging. The needle sits straight up and can go both to the right and left showing how much current the battery is being charged with or how much current it is being discharged with. If the ammeter is wired according to the MF 35 and MF 65 the ammeter will go in both directions, that means when the engine starts it will turn to the right to show a rather heavy charging in the beginning, moving towards the center when the battery is topped up. If the lights are switched on the needle will move toward the left, and if the engine is only at idle it may go to the left side of the face showing that more current goes out of the battery than the generator puts back in. According to the TE 20 diagram it will only show the charging, and when the lights are switched on the needle will not move a bit to the left, because only the charging current from the generator goes through the ammeter. In fact, if you turn the lights on if the tractor is wired according to the original diagram the generator will charge more so the needle will jump further to the right the more lights you are using. Can anyone enlighten me in this, were the old TEF 20 wired in such a way that you could only see the charging and not the discharging or is it only a mistake on the paper ?
Bill in Norway.
| 
