C120 auto brake set up help

[stevebo-(Moderator) 8,351]

I am trying to help a friend with his c series tractor. He is missing the mechanical portion the the parking pawl engages. Can anyone help me is a diagram or pics of the parking set up? What acts as the parking brake on this machine? Is it 100% hydro hold back? Thanks

[daveoman1966 3,762]

The PARKING PAWL in an internal part of the trans and here is a pic of it.  When the PARKING BRAKE lever is pulled UP, that forces the PAWL to engage a gear in the trans, putting it in PARK.  In almost EVERY case I've ever seen, that parking pawl is broken away or worn down, caused by pulling UP on the parking brake lever while still in motion.  That is why there is a decal that reads "DO NOT ENGAGE WHILE IN MOTION".  (or something like that).  However, it seems no one pays attention to that and they use it as a PANIC STOP, which chips away at the parking pawl (or gear) and these metal 'flakes' get into the trans fluid.  Those steel flakes work their way into brass parts of the pump and / or hydraulic motor and scrape or score precision parts, causing loss of power.  The only cure for that condition is REBUILD.

 

There are 2 types of parking pawls.  One has the shaft welded to it, and the other is a cast part, drilled for a roll-pin to hold it onto the shaft (like the one in the trans pic shown). 

My private email is::

daveoman@windstream.net

 

Edited March 17, 2014 by daveoman1966

[stevebo-(Moderator) 8,351]

Dave-

Thank you !! I should have known this since I rebuilt my tranny on my auto 18 a second time due to this design. I told him to FORGET gathering up the parts needed to make this work again. I told him to use a couple of wheel chocks... lol

[daveoman1966 3,762]

I also have a C-145 with sundstrand auto and it has a more conventional PARKING BRAKE on it.  That is, there is a BRAKE DRUM (similar to the 8-speeds) on the end of the Hyd MOTOR assy.  It has brake BAND on it, much like std trans have.  Not sure, but me thinks this desing is also on later models of the D series.