martinm

Can anyone help? My son's HBX WildKiller was a Christmas gift yesterday. Worked ok then. It worked okay this morning also. This afternoon the back wheels are moving in opposite directions...one goes forward and one goes in reverse. Any suggestions why this might have happened? How do I fix it???

collector1231

My Feedback: (1)

Sounds something like in the diff went wrong. Does it still drive okay?

RustyUs

Interesting buggy. Looks like a cross between an Armma Raider and a HPI Baja 5B.

Here is where the other half of the hobby comes into play..."wrenching". No ifs ands or buts about it, you're gonna have to tear apart the tranny and check the diff's gears. More than likely you have a exploded view type of manual the came with the buggy. If by chance you have a step by step manual...great! If not, it would probably be in your best interests take pictures as you go, and keep parts organized as you start tearing down the RC.

flyinwalenda

My Feedback: (5)

Is this happening when the car is off the ground?
When it's on the ground does only one wheel have power to move the vehicle?

martinm

No it won't move at all. Steering is okay though and the front feels will turn but the car won't move

flyinwalenda

My Feedback: (5)

With the car off of the ground and if you rotate one drive wheel forward by hand the opposite drive wheel will rotate in the opposite direction.....that is normal.
If the car is on the ground and the motor is running but the car won't move at all then it could be several things .
On the end of the electric motor shaft is a small gear(pinion) that is locked onto the shaft with a small hex screw. That hex screw could have worked loose and the pinion is not spinning as the motor shaft spins.
The pinion gear drives a larger gear(spur) on the transmission . That gears teeth could be stripped or the motor came loose from the mount; both cases would not allow the pinion teeth to properly engage the spur teeth and drive the transmission/wheels.
There should be a clutch (slipper clutch) on the spur gear. It is adjusted by turning a lock nut down over a coil spring to make the clutch grab and rotate the transmission as the spur rotates. That nut could have turned loose not allowing the clutch to engage.
All of the above should be housed under some sort of plastic cover either over the motor or at the end of the motor where it attaches to the transmission. A few screws should hold it on.
I can't find much info on this buggy let alone a manual. It looks like a cheaper china brand and I don't know where you could get parts (if you need them)without having to wait weeks.

cbaker65

That's normal on most rc's for one wheel spin one way , the other one the opposite!

That sounds more like a loose wheel nut ,or missing pin ,or even a set screw.

RustyUs

Little short vid to grasp the thought of how a geared diff works:
https://www.youtube.com/watch?time_continue=30&v=ObXpSMQ5UF4