XB not moving - clutch stuck

[ocy9]

i ran my xb for a few minutes when it started hesitating and then suddenly stopped. the servos and engine worked fine, so i tried pushing it and discovered that all four wheels were locked.


the car also gave off some smoke and a burning plastic smell a minute before this happened. i took the body off and discovered that the top right corner of the starter assembly cover was burnt.

 

[cordy]

Take off the bell housing and look at the clutch and spring.Check for stones in your gears,and center differential.

 

[ocy9]

the bell housing is the figure 8 shaped cover on the side of the car, right?

 

[cordy]

NO.Take off the gear cover,take off the gear plate,the bell housing attaches to the side of the motor,it`s round with a shaft that attaches your( a) gear. don't you have a manual to look at? You can get the manual at redcat racing on line. The clutch is inside the bell housing.The clutch looks like two small break shoes with a spring between the shoes,this is a 6000spring,if you change the spring to a 8000 spring you will have better take off.Also check that thier is no derbis between your coil and flywheel.The coil is under the engine cover on the pull start side. Hope this helps.

 

[Stygian]

NO.Take off the gear cover,take off the gear plate,the bell housing attaches to the side of the motor,it`s round with a shaft that attaches your( a) gear. don't you have a manual to look at? You can get the manual at redcat racing on line. The clutch is inside the bell housing.The clutch looks like two small break shoes with a spring between the shoes,this is a 6000spring,if you change the spring to a 8000 spring you will have better take off.Also check that thier is no derbis between your coil and flywheel.The coil is under the engine cover on the pull start side. Hope this helps.

I always find it a lot easier to just pull the engine

 

[ocy9]

i opened it up and saw the issue immediately. the clutch is fine, but the brakes aren't.the two brake discs are sandwiched between three steel plates, and it looks as though the discs somehow clamped on and literally glued themselves onto the middle steel plate. as soon as i yanked out that middle plate, the car was able to start rolling freely.any idea what caused this issue and how i can fix it? perhaps i was braking too hard and the discs got too hot? the brake/throttle servo seems to be working fine on the other hand. i've attached a pic so you guys can see what i'm talking about.





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[cordy]

Ok sorry I didnt remember that.You don't want your brakes to be full on(to tight).You want them to slow the platform down but not stopping completely.Use the fuel tubing and spring on your brake linkage.

 

[Guest]

There are two set screws behind the brakes that are use to adjust them. Those disks need to be replaced now. Looks like they possibly have been dragging for quite some time.???

 

[andyken]

Also the brake shaft has a set screw, it's two parts. A bad bearing can do it, but most likely the adjustment screws like RCdad said.

 

[Stygian]

RCDad is the brake system for the MT and XB the same, just curious as that diagram looks like it's for the MT.

 

[Guest]

Yep, the same. Most of those parts are even interchangeable between the two.

 

[Mike6000]

Are the adjustment screws part 50111? Not sure.

 

[Guest]

Are the adjustment screws part 50111? Not sure.

Yes. Those are the ones.

Some guys remove them and use spacers on the 2 pins that carry the three steel pads.

 

[Stygian]

Yep, the same. Most of those parts are even interchangeable between the two.

Awesome, that's very good to know, thanks.

 

[ocy9]

this was my first run and the brakes are already shot. awesome!

i don't plan on fixing the car until later tonight, but will i have to take apart anything else to adjust the set screws? i hope i can just remove the brake discs and access the screws from there...

 

[Guest]

The hex is on motor side. That's why some use spacers instead.

 

[andyken]

this was my first run and the brakes are already shot. awesome!i don't plan on fixing the car until later tonight, but will i have to take apart anything else to adjust the set screws? i hope i can just remove the brake discs and access the screws from there...

From the pull start side, if you take the mud guard off...and have a long allen wrench.

The set screws are behind the center drive ring gear...not easy to get to, but possible.

 

[ocy9]

before i try any of that, i'd really appreciate it if someone could explain how this braking system works in the first place. if i get an understanding of what's going on, i'd have a better idea of where to put the spacer and how to reassemble the braking system once i'm done with the repair.i stared at the brakes for several minutes and i just couldn't figure it out.





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[ocy9]

before i try any of that, i'd really appreciate it if someone could explain how this braking system works in the first place. once i figure out how they work, i can hopefully go ahead and fix the problem.i stared at the brakes for several minutes and i just couldn't figure it out. unless i'm missing some vital bit of info here, the attached diagram is how i think the brakes work. and i hope to god that i'm wrong because this looks like the weirdest braking system i've ever seen.the yellow things are the discs and the silver lines are the metal plates that go in between the discs. the black circle is the rod connected to the servo linkage.





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[Guest]

You are close.

The metal pads slide on the two pins. The adjustment screws set the location of the pad farthest in. The rod that is on the opposite side that the servo linkage pushes, applies pressure. This squeezes the disks. Hope this helps. It is hard to describe.