Can't Get Clutch Adj. On 1951 D4 Dozer .it Won't Lock In.

If you are at max ajustment on the collar, it may be time for a new clutch friction disk. Should be able to get an aftermarket for around $60.

If you think you have more ajustment left on the collar, I would start ajusting
the lever linkage. There might be too much slop in there and if you tighten it up, it might snap over center.

Good luck,
muzz

Too tight, it won't snap in
too loose it won't snap in, but lever will go farther than when it's too tight.
As Muzz says, could be the linkage is worn so that the lever hasn't got travel enough to snap the clutch in. You might have to replace some linkage pins with a bolt or oversize pin to get rid of the slack.

Could also have something come loose inside, probably would be a good idea to look in there and make sure all the links etc are in place.

Were Can I Get Aftermarket Clutch

If it's the clutch disc you are after try here: www.tractorparts.com/

maybe the tread on adjustement are no more god or the hole came and plate are no moregood or the collar ass. is to much use or the disc and have these parts except the disc.

I was adjusting the wrong thing i was adj. the rod not the adj.on the clutch.now i need the leagth for the thread rods on the hand clutch.

There is no set adjustment for the threaded yoke/rod. Just adjust it for your level of comfort and range.
When you push to lever all the way forward you should also activate the transmission shaft brake in order to minimize the gear grinding when shifting.

thanks old magnet