YM276D Brakes

[California]

It sounds like the cover is free of the housing, so that has to be the shoes too expanded to come out of the drum. Is it certain that the brake lever is in brakes-released position?

If i were doing that project I might lay the removed wheel under the tractor for safety, then run the tractor in gear, forward and reverse, to make the brake drum move relative to the shoes and hopefully break them free. Think safety!

 

[Jtullis13]

It sounds like the cover is free of the housing, so that has to be the shoes too expanded to come out of the drum. Is it certain that the brake lever is in brakes-released position?

If i were doing that project I might lay the removed wheel under the tractor for safety, then run the tractor in gear, forward and reverse, to make the brake drum move relative to the shoes and hopefully break them free. Think safety!

California you have the right idea on both parts of this! Great suggestions

 

[richriddle]

I have been away a few days but decided to take off the left rear brakes to determine approximatly what position the lever should be located; after all, both sides need to be replaced.

 

[richriddle]

It sounds like the cover is free of the housing, so that has to be the shoes too expanded to come out of the drum. Is it certain that the brake lever is in brakes-released position?

If i were doing that project I might lay the removed wheel under the tractor for safety, then run the tractor in gear, forward and reverse, to make the brake drum move relative to the shoes and hopefully break them free. Think safety!

I removed the left brake in about two minutes doing exactly the same thing done to the right that remains frozen (for lack of a better word). The rear tires are reinstalled in place for safety if the YM276D fell, it would land on the tire. As you suggested, when the tractor runs, the left wheel spins free and the right wheel is locked in place. The right wheel rotates just a hair. When the tractor is turned off, you can move the entire assembly by hand about five degrees, but it wont' budge after that. The five degrees is the approximate distance it can travel before the cover contacts another part. Prior to today, one needed a tool to move the assembly the five degrees. Since the YM276D is up on jacks in the rear, it might be possible to throttle more power than the simple low idle to see what happens. Here are a few of the pictures of the left side brake.

 

[richriddle]

I increased the throttle today and it didn't change anything. The left wheel spins with the throttle but the right wheel is frozen. When moving the wheel by hand, it looks like the slight movement of 5 degrees on the right wheel isn't moving inside the drum, but has the entire drum moving as well, in other words frozen to the walls of the drum. I am guessing that because when the right tire moves the 5 degrees, the left tire also moves five degrees.

 

[CoyPatton]

Trying to grasp the issue from your pictures and descriptions and am somewhat confused. I admit I have not ventured into my yannie’s brakes (perhaps I should before an issue). Since you have the one side loose and shoes removed, could you reinstall the plate, and compare the movement of the brake camshaft lever from the disassembled side to the ‘frozen’ side. This would give you a reference to travel and then perhaps a reference to the cam position on the stuck side.
Another though is to unbolt the cam shaft and upper pin to remove the outer plate. That way you can at least see where the shoes are stuck at and perhaps disassemble from there.
Again I have not been into mine, but your upper pin appears to have a nut, Hoye’s diagrams show nuts. With an O-ring in the camshaft for movement and a replacement available from Hoye, it comes out some how.
If like vehicle drum brakes, the shoes have cut a groove into the drum and are locked behind it. Either the camshaft is stuck/frozen or the spring(s) have broken and have the shoes jammed.
Good luck!

 

[richriddle]

Trying to grasp the issue from your pictures and descriptions and am somewhat confused. I admit I have not ventured into my yannieç—´ brakes (perhaps I should before an issue). Since you have the one side loose and shoes removed, could you reinstall the plate, and compare the movement of the brake camshaft lever from the disassembled side to the ç´*rozen side. This would give you a reference to travel and then perhaps a reference to the cam position on the stuck side.

You are correct. I did just that and have the lever and the cam position of the opposing plate in the position that would not be forcing the shoes apart.

Another though is to unbolt the cam shaft and upper pin to remove the outer plate. That way you can at least see where the shoes are stuck at and perhaps disassemble from there.
Again I have not been into mine, but your upper pin appears to have a nut, Hoyeç—´ diagrams show nuts. With an O-ring in the camshaft for movement and a replacement available from Hoye, it comes out some how.
If like vehicle drum brakes, the shoes have cut a groove into the drum and are locked behind it. Either the camshaft is stuck/frozen or the spring(s) have broken and have the shoes jammed.

I will attempt to remove the upper pin from the left side that is already out. My guess is that it will need to be pressed out, but that's just a guess. If it requires a press, it won't happen in the tractor. You might be right about the shoes cutting a groove in the drum. The camshaft now moves and isn't frozen. There is no room to see if springs broke. I might get a larger dead blow hammer to see if it can jar something loose.

Good luck!

Thanks

I appreciate your response.

 

[rScotty]

Rich, have you unscrewed the studs to see if that gains you anything?

Later...editing.... Well, I thought that they were studs, and I thought you said you had removed cover nuts.
But I just looked at the YM276D parts manual and it shows the cover held on by bolts. Odd.....
rScotty

 

[California]

The left wheel spins with the throttle but the right wheel is frozen. When moving the wheel by hand, it looks like the slight movement of 5 degrees on the right wheel isn't moving inside the drum, but has the entire drum moving as well, in other words frozen to the walls of the drum.

Pressing the left brake should apply all the engine torque to the right side. In the lowest gear, this would be substantial force, perhaps enough to break something. I would try that, reverse first then forward, but think safety!!! Reverse first, because I assume forward motion jammed the shoes somehow. Maybe a lining came loose and climbed over the other lining?

 

[CoyPatton]

Before I tried to apply a low gear torque to one wheel (lots of force with a low range low gear) lots of things to potentially damage other break loose a jammed/stuck/frozen brake shoe, I would try prying as near as possible to the pin and cam pin. Do not get real carried away at prying, but the effect I am suggesting you try to recreate is the tendency of the shoes to want to spring to the middle. I watched Hoye’s brake video again and with little apparent pressure in the video, the shoes ‘folded’ toward center away from the outer plate. I suggest to attempt to pry equally near each pin at the same time. Also realize that if the shoes spring loose any pressure released will push outward, so be prepared for possible flying pieces.
Again Good Luck!