first of all, i think i now understand the foward/back - looking at the cartoon, when the h/l selection shaft moves forward, it sends the 4wd shaft the other way.
I now have rebuilt the 4wd gearbox back. I can't see any difference to what i have built now and what i built before, but now it behaves correctly (at least at the moment, with the car on axle stands).
I have now done the measuring of the shafts, as per the linked attachment.
RESTATING THE "STANDARD" MEASURES from the link:
HIGH 2WD
high/low 68mm
4wd lock 15mm
4wd shaft 27mm
HIGH 4WD
high/low 68mm
4wd lock 27mm
4wd shaft 51mm
LOW 4WD
high/low 44mm
4wd lock 15mm
4wd shaft 51mm
MY MEASURES (highlighting significant differences)
HIGH 2WD
high/low 60mm to end main shaft, 80mm to end threaded part (not exactly sure which is correct measurement, suspect the latter)
4wd lock 15mm
4wd shaft 15mm
HIGH 4WD
high/low 60mm to end main shaft, 80mm to end threaded part
4wd lock 34mm
4wd shaft 50mm
LOW 4WD
high/low 44mm
4wd lock 15mm
4wd shaft 51mm
I am thinking that when i move it to HIGH, the h/l shaft is moving too far forward, so the 4wd shaft then moves too far back - and this could then encourage the shaft(s) to come off the Coupling (which would then cause my mechanism to stop working).
I don't know why the h/l shaft is moving too far forward.
What I think i could do is put a few washers on the end of the main shaft so that the connector to the lever is further forward i.e. when i move the lever forward, the shaft doesn't move so far forward.
But it would be nice to know why it is happening?
