Re: (ET) speeds 5,6,7,8 E20]

[RJ Kanary <rjkanary consolidated net>]

            Do you get Speed 5, the only reduced field speed that is available without the FW relay contacts open ?  If you don't have Speed 5, suspect switch FW 1 or its wiring at the throttle.
 
           Card 4 'senses' armature current draw to determine whether or not to allow field weakening.Two places it 'looks' at are directly across the armature,(Wires 8 and 24) and at the sensing shunt, (Wires 4 and 54).There's two good places to look for compromised connections if the FW relay is dropping out.

             Another area pretty high up on the Hit Parade is the card edge connector on Card 4 itself.They love to split lengthwise causing all sorts of incredible gremlins, up to and including eight speeds in Reverse.{That's an attention getter when you are maneuvering and just mash the throttle to back up, expecting only four speeds, <VBG> }

RJ


Mike Finck wrote:

I need some diagnostic help!

I am unable to engage speeds 5,6,7,8 on serial number 26AE20DA. I can engage those speeds while in neutral or when the rear wheels are raised off the floor, but when moving across the driveway they will not, Field Weakening coil FW does remain energized (open).    However, once, during a moment of frustration this weekend I stomped on the foot speed control repeatedly and the tractor unexpectedly leapt to life and away I went at 9 mph but when I had to let off because the driveway ended, I was back to not being able to engage higher speeds again.

 

 

 

Michael H. Finck

Email: m finck setterlin com

 

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