4420 Brakes

[61-4010]

Having issues with the brakes on my 4420 so I'm going to rebuild the master cylinder and slave cylinders. Got to thinking that for a 43 year old machine maybe the brakes themselves need replacement.

Apparently, after reviewing the schematics and other posts, the 4420 doesn't use brake pads/shoes but something called actuator disks. Each side has 2 so 4 in total. New ones are over $200 each!

That said, how do these actuator disks work and do they need to be reviewed for replacement? How can I tell?

Thanks for the education!

 

[wore out]

They are disc brakes with ''cam'' actuators using ramps and 5 steel balls, similar to what a lot of older tractors used.

ONE complete actuator assembly (9) is used per side, along with two lined discs (1).

You won't know what you need 'til you get in there, unless badly worn or rusted to pieces or otherwise damaged the actuators can be cleaned up and re-used, replacing the springs and balls as needed.

Perhaps all it needs is new disks, or in a worst-case scenario everything in there may be ruined of the brakes have rusted up/stuck and have been overheated and worn out.

 

[LonM]

Our 4420 had no brakes because the master
cylinder and the two cylinders down on the
axle were worn out and leaking.

After putting on two new cylinders down on
the axle (found on the net, as Deere
wanted around $400 each), I also honed out
and rebuilt the master cylinder. That got
the mechanical linkage to the discs
moving, but I still didn't have brakes.

The disc/ball setup was way out of
adjustment, so I took a lot of free play
out of it. The result of all this is a
combine that can stop if it needs to, but
I've heard that the brakes on these
4400/4420 combines weren't all that great
even when new.

I reverse bled the lines from the axle up
to the master cylinder with a hand pump
bleeder tool.

Good luck,
Lon

 

[4520BW]

I have had to ruff up the discs on them before. They get glazed over easily.