Ford 340A brake sticking

[bcharest]

Hi folks. New posting here so hope I'm in the right thread. I've a 1983 Ford 340A Industrial Tractor with a backhoe. The right rear brake seems to be sticking, my land is not super level and the hoe makes in light in the front so I'd like to fix the brake before it causes a mishap ending my short tractor owning career. Anyone ever do brakes on one of these things? I did buy the service manual but would like to have a better idea what I'd be getting into if I try to fix it myself. I asked a local shop about it once and he said it was a pain in the rear job that he wasn't interested in. My budget is a little tight so having it trucked off somewhere else is problematic. Haven't found a youtube video or anything. I'm pretty mechanical and have some tools. Appreciate any guidance. Thanks, Brian, Windsor, VT.

 

[Destroked 450]

Explain sticking
340 has inboard wet disc brakes that rarely give trouble, they do wear out but most time you can still have pedal but no stopping power
1st thing I’d check is the brake return springs under the right foot board, without the return spring the pedals will not return to the top position and just the weight of the pedal will cause the brake to drag
If the pedal goes more than half way down to the foot board the brakes need adjusted, simple adjustment of the linkage under the tractor with a couple 3/4” wrenches, properly adjusted the pedals should have 1 1/2 - 2” of travel

 

[bcharest]

The brakes occasionally make a kind of dragging noise and yesterday when I was driving down a 10 or 15% decline the right wheel would turn and then lock for a second or two while I wasn't touching them. A couple days ago I couldn't get the tractor to turn in my dirt driveway. I turned the front wheels and the tractor would still go straight. The spring is missing so it could be that. The two pedals are frozen together and yesterday after I posted I tried to remove them. Took or the cir-clip on the outside off but still couldn't pull off the first pedal, even after pb blaster and tapping a wedge between the two. The bolt that holds the inner (left) pedal snapped off when I tried to remove it. I'm guessing there's a notch in the shaft and the broken bolt it holding it in place. Even the pin that holds the linkage into the rear axle is frozen so I've order a set of oxy acetylene torches (which I've always wanted) to help get that stuff apart. Once I get everything freed up, find and install the new spring (springs) I'll post again with the results. Previously the brakes seem to work ok. They weren't great but stopped the tractor on the mild slopes I'm comfortable working on. I don't mind doing the brakes if need be I just don't want to open the axle to find out the part I need to remove weights 200 pounds and is hard to get back together. Thanks very much for your reply.

 

[used red MN]

A couple days ago I couldn't get the tractor to turn in my dirt driveway.

Hello bc, I’ll give you a ‘welcome’ even though you have been here a while but haven’t posted much. If you tractor would not turn either direction in the dirt that is a reaction to the differential lock being engaged. The differential lock is a bar type lever that comes out of the gear case behind your right foot when seated on the tractor to drive it. The bar would be pushed down towards the floorboard to engage it. If it is down see if you can pull it up. You one wheel locking would be more likely a symptom of a brake locking or unfortunately a problem in the final drive in the rear end.

 

[bcharest]

Hi Used Red MN, all. The problem has went away at least for now but I did use the differential lock a number of times recently including just before this issue happened. I just took a few measurements and if I lift the lock pedal up with my hand or foot and then release it, it drops about 1/4" (see attached pic). If I push down on it with my hand (only 10 or 20 pounds of force since I'm kneeling next to it trying to get a picture) it only goes down about another 1/8". The lever is about 4.75" so according to my calculations the shaft it rotates drops about 3 degrees under the weight of the pedal and 4.5 degrees with a little push. I'm wondering if the hydraulic connecting rod which I guess you'd call a strut is doing it's job. If it's supposed to be pushing the lever arm up to keep it all the unlocked maybe I need a new one of those? Thanks, appreciate your help.

 

[Jim.ME]

That connecting rod has a spring in it I think. The purpose is when you press down on the pedal the Differential lock may not be aligned to lock in, the spring provides a way to allow you to keep pressure on it so it will engage as the components align. There is a spring inside the differential housing that keeps the coupling disengaged from the differential. You need to be sure all the external linkage works freely, no drag. You may need to lift the pedal up to be sure the lock disengaged, they can stick in. I agree with used red MN your problem sounds like the differential lock was hung engaged.

 

[used red MN]

Hi Used Red MN, all. The problem has went away at least for now but I did use the differential lock a number of times recently including just before this issue happened. I just took a few measurements and if I lift the lock pedal up with my hand or foot and then release it, it drops about 1/4" (see attached pic). If I push down on it with my hand (only 10 or 20 pounds of force since I'm kneeling next to it trying to get a picture) it only goes down about another 1/8". The lever is about 4.75" so according to my calculations the shaft it rotates drops about 3 degrees under the weight of the pedal and 4.5 degrees with a little push. I'm wondering if the hydraulic connecting rod which I guess you'd call a strut is doing it's job. If it's supposed to be pushing the lever arm up to keep it all the unlocked maybe I need a new one of those? Thanks, appreciate your help.

Lift the rear wheels off the ground with the rear stabilizers. Rotate a wheel slowly and apply pressure to the diff lock engagement lever a see if when the internal lock teeth engage if that will allow the lever to move down farther for engagement. Also if the left brake works you can start it put it in gear and see if both wheels spin when it locks, but also with it released the left brake if working should stop the left wheel but allow the right wheel to continue to turn. Here is a link to the manufacturers online parts catalog for that tractors. The link will allow you to view all parts diagrams for your tractor, on a phone selecting “Table of Contents” takes you to the menu for the Functional Groups. CNHI Ford 340A brakes diagrams

 

[bcharest]

Finally got the brake pedals off. Seemed like it would be an easy job but tough sledding to get the first, right, pedal free. Not much room to work or swing a hammer with the backhoe and loader frames right there. Attached is a pic of the shaft the pedals connect to as well as the parts diagram. It looks like there has to be an inner and an outer shaft or else no point in having two brakes but as near as I can tell they’re about fused together. The previous owner didn’t take care of it so the two brakes, as mentioned above, have been stuck together for god only knows how long. I measured the shaft diameters; 1- 1/8” on the inside left brake and 1” on the outside right which means the outer piece that slides over the main inner shaft is only 1/16” thick. I get that hardened steel is pretty strong but it seems odd. Any thoughts on the best way to proceed to free the outer from the inner shaft? I could put one or both of the pedals on to get some leverage but that might make heating it a little harder, especially as I’m a rookie with the torch set. And I’m also not sure how much heat I can put to it without damaging some seal that might be holding in the oil. I also don’t want to damage the outer piece if it’s only 1/16” thick right there. I see the shaft connects thru to the other side for the clutch and it’s quite free as I can turn it by hand. Hopefully it won’t come to that but possible to change the whole shaft if need be?

Thanks very much, Brian.

 

[Jim.ME]

Am I missing something or reading this wrong? The shaft going across the tractor to the left brake is a stepped shaft, there is no other piece to heat and free. The left pedal is keyed to that shaft, so it turns with the left pedal to operate the brake linkage ked to it on the left end. The right pedal is free to rotate on the outer 1" diameter area as the brake linkage connects direct to the pedal. The left pedal is locked to the shaft by that key. The right pedal appears to have a bushing in it and should turn freely when on the shaft. You may only need to clean up the 1" area where the right pedal mounts so the pedal moves freely.

 

[showcrop]

If you stopped by Reed equipment John or Jason would probably give you some pointers.

 

[bcharest]

No, you weren't missing anything. I misunderstood how the whole thing works. This makes a LOT more sense! I'll get it all cleaned up, maybe replace the bushing and report back. Showcrop, you must be near by if you know John and Jason. Awful nice folks. Thank you all again.

 

[Destroked 450]

I see why it’s sticking now, apparently the previous owner always keep the pedals locked together, which I see a lot on backhoes
This allowed the outer pedal to rust and stick to the cross shaft which also rusted
If you look at the back of the outer pedal you’ll fit a grease fitting or hole were a grease fitting goes
These rarely get greased but operation of the pedals independently would have keep the outer one from sticking to the shaft
Polish the outer portion of the shaft with emory cloth and shine up the inside of the bushing to where the pedal will easily slide onto the shaft, make sure the fitting will take grease or replace it while making sure the grease hole is open. Wipe a little grease on the shaft and in the bushing and reinstall the pedal

 

[bcharest]

I did notice the grease fitting and in hindsight that should have been my clue. I've ordered a new fitting and bushing along with some new springs. thx.

 

[showcrop]

No, you weren't missing anything. I misunderstood how the whole thing works. This makes a LOT more sense! I'll get it all cleaned up, maybe replace the bushing and report back. Showcrop, you must be near by if you know John and Jason. Awful nice folks. Thank you all again.

My wife's sepfather was from Windsor. My wife grew up in Unity and we live in Chester NH. I know John and Jason from the tractor club and tractor pulls.