need help with braking system case ck680 1974

[jb35007]

i have a 74 case ck 680 and i'm having a hard time stopping this beast the brakes have been bleed and i have a firm pedal but i have to put over 200 lbs of pressure to get this thing to grab and stop the wheels...

so my main question is , is there some sort of hydraulic assist for the braking system that maybe isn't working or that i missed????

there is a round pad bolted on the back of the motor that moves freely when i push the brake levers but i am unsure of it's purpose???

all i know is this can't be the actual way the brake system was designed also down on the brake canister i only get maybe 1/4" travel when the brakes are pulling the rod out.

please help,
jeff

p.s.
i adjusted my emergency brake to where i can barely set it and if i lift the rear tires off the ground and put it in first and forward gear (shuttle shift) the parking brake barely stops the wheels from turning....

 

[DJ54]

Probably best to get the serial number of your machine, then go here, and select the one you have. Official Case Construction Equipment Online Parts Store and Parts Look Up. Parts for Case Equipment and Construction Equipment. Parts Store for Case Wheel Loaders, Case Excavators, Case Skid Steers, Case Original Parts.

That old of a model, I'm guessing they still used brake fluid in the system. My 480 is a '79,and brake fluid is still used. Somewhere along the line on the newer ones, they used Hy-Tran.

I'll assume it's the twin disc brakes on it. Mine were so packed full of dirt and dust, then hardened by moisture, it really had the inside of the brake chamber to the point, it would barely stop it too. Thankfully, the seals behind that on the bull pinion shaft did not leak. If you've got differential oil showing like it's leaking below the brake cambers, could be the seals are out, and have the disc's soaked. Stepping on the brake pedal is pretty much like stepping on a plum, and not much happening. The ball bearing in mine were pitted really bad,and had a ring cut in them, and just would not hardly move. I got all new ball bearing, and springs for mine, through a company I added the link for below.

I took a quick look at the brake system you described. That appears to be a hydrovac system on the brakes. Didn't look far enough to see where it picks vacuum up, maybe that has to do with the hard pedal,and not much action. Never saw anything like that before. Mine just has a brake line down to a wheel cylinder to activate the same type of brake.

Hopefully the link above will give you enough info to do some trouble shooting.

If it comes to the point you need new brake parts, compare here before you get them anywhere else. Remanufactured Transmissions, Torque Converters, Engines - Joseph Industries They beat everyone else hands down on all parts, including new master cylinders I needed.

The easiest way to shop for new parts is to copy and paste the part number from the Case site, then do a search through a search engine. I've had the best results using Google. You may need to call Joseph Ind. to get prices, but I think it may be worth the call. I'd venture to say if you needed parts, and ordered before 10:00 am, you'd have them at your door within 2 days.

 

[jb35007]

Your response was a bit confusing
1st where do I locate the vin # on the tractor?
2nd my brake lines go straight each master to a slave cylinder to the brake assembly but there are other linkages and a bar that goes side to side and that is where the round pad of sorts that comes out of the block?
3rd I have had the brakes apart and they look relatively good they just don't stop for crap!
Kinda like in a car that has vacum power brakes and you try to stop the car with the engine off and not removing the vacuum plug

 

[DJ54]

If your hoe has a cab or ROPS, open this link,and it will show the serial number location. Official Case Construction Equipment Online Parts Store and Parts Look Up. Parts for Case Equipment and Construction Equipment. Parts Store for Case Wheel Loaders, Case Excavators, Case Skid Steers, Case Original Parts.

Sounds like you have the same type brake system as I do. Here is an exploded view of the one for the 680. Official Case Construction Equipment Online Parts Store and Parts Look Up. Parts for Case Equipment and Construction Equipment. Parts Store for Case Wheel Loaders, Case Excavators, Case Skid Steers, Case Original Parts. That little brake cylinder doesn't have much of a stroke, so you may just need to snug #47, up in the exploded view, if there is any adjustment left.

Don't have a clue about the rest of it, as far as the round pads are concerned.

 

[jb35007]

yes i found my serial plate and i have a 680-b so it looks to me that it is kinda like a clutch setup for braking... and the plate looks to me to have meat on it so to say? i'll post a pic for opinions

 

[DJ54]

Looks like you have a leaky seal. You can clean those up, but it takes more than spraying with brake cleaner. This is a trick I learned from a couple of Case owners I personally know, that has had them for years, and had mechanics tell them to do this.

You need to suspend those disc's in a fashion, so as to have good clearance on both sides. I hung mine on a piece of 3/8" rod, clamped to my old hydraulic press that sets outside. Just be sure to be away from anything flammable.

If you have a propane torch, fire it up, to like medium setting, and run the flame directly on the facing. Stay on it long enough, and it will literally boil the oil out of them. My first thought was, it would surely cause them to lose their bond to the plate, but they assured me it wouldn't. The one fellow has been doing it to the same set on his 630 for years. It will take a while to get it all out. You'll not believe how much oil is in them. When the oil stops boiling out, let them cool, and do a final clean with brake cleaner. I buffed mine with a medium Roloc pad, but some fine sandpaper will buff them too. This will get you by for a short while, until you replace that seal. Last I bought were like $15.00 ea.

The seal on the bull pinion shaft, is notorious for leaking on all models with this type of brake. Not a real bad job to replace, but I have a few pointers I've picked up from another forums from old mechanics that shared their tricks of the trade, and makes it a lot easier.