Gear grinding or shaving? (Updated Post) PLEASE HELP!

[ChuenouXiao]

Thanks to all the good help here I've manage to fix and replace my crown gear and my pinon gear successfully. I've replaced the four stock screws that were coming loose due to vibration from the crown gear (causing gear shaving and grinding!). The stock screws I've replaced with four new longer flat head screws along with locking nuts so that they won't ever come off again. I was very careful about putting everything back together to mounting engine properly, gears, screws and locktite where I think is necessary. Now everything seems to work fine but there is one problem. The break shaft won't retract to its default position. Note I was careful to make sure I installed the small break pad on the left side and the large pad on the right side when viewing from the attached pix below (note the shot below is when the servo is in default position). I even mark the two servo linkage for acceleration and break so that I can simply put it back properly. Its almost like the break shaft requires some kind of tension to get it to retract to the default position marked below as blue in the pix. All this and I still have the problem below. Please help me and tell me what I'm missing that is causing my break shaft thingy to not go back to default? Any idea? Your help will be greatly appreciated!

 

[Deluge]

The brake cam on my MT doesn't go back that far. If it binds when you try to roll it, you might have to adjust them, if that's even possible on the XT/XB. My MT doesn't have anything that moves the brake cam back to neutral, it just happens when I roll it forward. The brake pads kick it back into place.

 

[rcgasser]

The brake cam on my MT doesn't go back that far. If it binds when you try to roll it, you might have to adjust them, if that's even possible on the XT/XB. My MT doesn't have anything that moves the brake cam back to neutral, it just happens when I roll it forward. The brake pads kick it back into place.

1+ thats how mine have always worked.

 

[ChuenouXiao]

The brake cam on my MT doesn't go back that far. If it binds when you try to roll it, you might have to adjust them, if that's even possible on the XT/XB. My MT doesn't have anything that moves the brake cam back to neutral, it just happens when I roll it forward. The brake pads kick it back into place.

Deluge, what do you mean by bind? Adjust what and how? Please explain so I can fix it... thanks a lot!

 

[ChuenouXiao]

The brake cam on my MT doesn't go back that far. If it binds when you try to roll it, you might have to adjust them, if that's even possible on the XT/XB. My MT doesn't have anything that moves the brake cam back to neutral, it just happens when I roll it forward. The brake pads kick it back into place.

I see.... I think I know what you mean.... It looks like I have two options.

1. Buy a servo link lock and attach it to the servo link so that when the servo return to default after breaking, the brake cam have no choice but to retract to the default position because of the lock holding on to the link.

2.Figure out why its not going to default automatically without the mod of linkage lock.

I don't like the second option.... but prefer to follow it because I might have done something wrong..... please help people!

 

[ChuenouXiao]

I've manage to fix my problem through servo linkage re-adjusting (on the acceleration and breaking servo) and adding a brass collar lock on the linkage to bring back the break shaft to default position. Test run and my car runs like a champ so far with no problem. I guess sometime, you just have to figure things out yourself...... If anyone have any similar problem regarding the break shaft not going to its default position, please do share....

 

[JimmyJay]

In the pictures it looks like your missing the collar on the end of the brake linkage.

 

[DemonRC]

Keep an eye on the brake adjustment screws. Sometimes they back out away from the pads and the brake cam will not have enough "throw" to fully engage the pads.

 

[ChuenouXiao]

Keep an eye on the brake adjustment screws. Sometimes they back out away from the pads and the brake cam will not have enough "throw" to fully engage the pads.

THANK YOU SO MUCH! I saw those when I took it apart but I wasn't really aware of it's purpose. Now that you've mentioned it I will try to adjust it to see if it works and will update you and people here on it. Thank you so much Demon! Been working lately so haven't got time to look into it.

 

[ChuenouXiao]

In the pictures it looks like your missing the collar on the end of the brake linkage.

Does your XB come with a collar? I never needed one (it never came with a collar) and it works fine until after I did a complete disassemble of my car for my gears that were grinding. After this, I'm having the breaking issue. Servo linkage readjustment and collar doesn't seem to help. Demon have given me a good tip above so I will test that when I have the time and will keep you guys posted, thanks.

 

[Deluge]

Let us know how it goes. That's what I meant by adjusting them. The MT has two set screws just like that, but I wasn't sure if the XT/XB had them. So, I'm glad Demon cleared that up.

 

[ChuenouXiao]

Let us know how it goes. That's what I meant by adjusting them. The MT has two set screws just like that, but I wasn't sure if the XT/XB had them. So, I'm glad Demon cleared that up.

Will do, thanks.

 

[ChuenouXiao]

OK people! Here is the update.... I've figure out that one of the set screw that Demon recommended me to double check is missing (HOW THE FREAK DID THAT HAPPENED?). I replaced both with a slightly longer set screw from Ace Hardware and adjust them accordingly for proper breaking. My XB seems to be working fine now. I still leave the collar on where I've added just to make sure it doesn't break when I'm driving causing my pad to ware faster. Just so that you guy will know what's going on. Thank you all for the help!!!!!!!!!!

 

[Deluge]

Awesome. Glad you got it sorted.