Need help PLEASE, info on '06 brakes change

Does any one what IH all changed when they changed the brakes on the '06 series? I am told they increased the thickness of the plates, but from ? to ?. I could really use some help. Did they increase the depth of the outside cover(drum)as well? Did they increase how much the brake shaft protruds from the transmission housing too? Are the 806 brakes any different than the 706? My 806 had a 706 rearend put in it, and it is obvious they mixed something up in the brakes, the plates, pads total thickness is a little thicker than even the outer cover(drum), I am assuming this is why my brakes lock up as soon as tractor is started. Please please help. I need this tractor running asap, and cant seem to find any one that has the answers. The brakes have dragged since I bought it. The plates are not warped. New springs have been installed. All brakes related valves and presure regulators have been removed and inspected and rebuilt. When you open the bleed screw with tracotr running you can easily hold back the fluid with your finger so I know it isnt too much pressure getting by the brake valve. Also, with brakes adjusted, and the tractor started, you can only push the brake pedals in about a 1/2" max. I really belive I have too much "guts" stuffed into that brake cover, but I need to know what it is that is supposed to be in there. IT manual doesnt adress anything about the change.

If you go to the parts section on this site and look up brakes for a 706 or 806 you will see there is a difference in the outer and intermediate plates when the change took place. The serial# breakdown is indicated. It seems that most of the other parts are the same. Hope this helps.

In my opinion two things need to be addressed.
The first is the actual lockup, and the second is the brake action.
I have not ben into the brakes on these, so this is an external construct of the way it works.
The hydraulic system has a pressurizing control system (MCV)supplying working pressure to the brake system.
This pressure is dead headed at the control valving Prt#28. When the brakes are applied, this pressure is directed to the brake cylinder/piston, Prt#1, and 11.
Sa pressure builds, the piston compresses the materials of the disks and stops the shaft.
When the pedal is released, the piston returns as the fluid is blead off to the return pipe Prt#14.
and the pressure remains at near zero in the cylinder.

This seems to be the case in your tractor because the pressure is at or near zero when the engine is running, and a bleeder is open.

If the brakes were getting pressure, the bleeder would be under direct pressure, and making a mess.

Questions:
Does the bleeded make a mess when the engine is running and the brake is applied with the bleeder open?

Does the loosening of a brake apply tube (parts 32 or 34) (with a pan under it before starting) cause a mess?

If no real pressure/mess is hapening in the above, I believe your issue is in some other system!

If the wheels (and therefore the pinion shaft) are free when the tractor is shut off, then the brake components inside the drum/housing cannot be binding in the housing in the relaxed state. Thus I believe they would not bind with the near zero pressure supplied from the valve.

Is there a TA in the tractor. If yes, there could be the application of both front and rear clutches at the same time, thus preventing motion. These TA clutches are hydraulic. one locke it in direct, the other locks it in TAreduction to avoid coasting. If the levers are removed, the system might still be inside, as it hads been dramatically reconstructed.
If it does not move with the brake lines removed or loose, This is my best guess! Jim

J- Fluid does flow out of the bleeder when the engine is running, more so than with brake pedal not depressed. Note, the brake valve was tried on another tractor and worked fine.
Loosening of the brake apply tube does make a mess when the brake is applied.
The tracotr does not have a TA. Also, we plugged the ports that go to the brakes pistons in the brake valve and started the tractor to see if it was anything other than the brakes locking up when running. The wheels were free turning. That is what is so confusing, every test says that everything up to the brake assemly area. When you stack all the plates and pads in the outer cover(drum) there is only a few thousanths of an inch from being equel to the depth of the drum. Less than the thickness of the bonded disk(insulator) on the brake piston.

On the brake tube, it doesnt make a huge mess, but does have flow.

Dave i do not know what to tell ya on yours, Believe me when i tell ya that i have lot count on the 06's that i have worked on over the years and i have never run into your problem . I use to by 706-806's at sales and drag them home and go thru them and resell them like 2-4 every week and some of my buys were shell we say a learning experience some i was proud of and some came home under the cover of darkness , but when they left the shop they were go to the field ready . Worked on a lot of brakes to the point that i kept parts on hand to rebuild at the drop of a hat but never have i ran into the problems your having . And for the life of me i do not know where to tell ya to go . If the return springs are good and the adjusters are set correctly to start with then everything should work . no as for the S/N break i was not aware of that because i never ran into that yet but it is one of them things that you tuck away and remember so if you run into it then you know. As for any difference between the 796-806 rear ends i do not think so as my 806 that i have now is a MUTT because it has a 706 center section from being broke in half from a tractor truck wreck many years ago . Now as for your brake pressure on the brakes when the engine is running then for some reason pressure is backing up someplace and it is by passing for some reason what is causing it i have no idea or why it is happing . Myself i have only had one I H tractor without a T/A and it was a factory T/A delete and after trying to sell it for 6 months with no takers it went to a sale and i lost more on it then if i sold one with a bad t/a and never bought one after that.If it had a bad T/A it got a new Hy Cap T/A and sold with a warranty . I really do wish i had and answer to your problem . But i am not even close enough to even think about coming out to help ya. And that i have done already for Andy .

Some flow from the brake valve in the off position should be OK as long as it does not build pressure. I think you will find that your problem is in the return springs. They almost always need to be replaced when the linings are replaced. Your old ones may feel OK but if you match them up with new ones you will find that they are now too short.

As the brakes are applied the piston pushes against the adjuster plate which pushes in on the springs. The more the linings wear the more the springs are collapsed. When the brakes get hot the springs will lose some of their temper and no longer apply the same pressure to retract the piston allowing the brakes to drag causing the brakes to get even hotter.

The brake adjusters work to limit how far the piston is pushed back into it's bore. If there is a problem with the adjusters it is usually either that the brakes are slow to apply because the piston has retracted too far and takes too much oil before applying the brakes or poor braking because the adjuster screws are seized they are keeping the full pressure of the piston being applied to the linings.

The 706 and 806 are the same brakes. Both tractors were changed to have different primary plate, intermediate plate and drum. So, you need to have all three correct parts. The self adjusters were improved but either will work. You have to be sure to back that self adjuster off each time you remove and install brake. The return springs have to contact the lugs on primary plate to force piston back against self adjusters(make doubly sure of that. You should be able sneak a gauge underneath after assembly (not 100 percent sure on those anymore but can on some models) to make sure discs have like .020 clearance. Problem I am having from this end is if you had wrong parts it would lock up before you started engine or have no brakes at all.