Big Rock Wheels not turning and motor is whining

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SaltyLocal

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I had to replace a shock arm on my sons BR and while the shock was off, I decided to top off the fluid. Once reassembled, the front wheels no longer turn. Initially, it was making very wide and delayed transmitter response turns. Then it simply stopped turning, motor now sounds like a squealing mouse, and the truck no longer moves forward or backwards. Any ideas? At one point, I put a fresh 2s battery in it, turned the remote and then the truck on and the wheels started spinning full blast with no remote applied throttle while on the bench. I didn’t even have the remote in my hand, so I know I didn’t accidentally bump the throttle. Thankfully, I had it up off the ground.
 
Start at the motor and make sure it spins freely, disconnecting it from the spur and pulling the trigger. Then check the slipper and make sure it turns. Then check the front diff and make sure you can turn the wheels, and if you still can't turn the rear, time to pop open the diff and make sure all the gears can spin freely.

Something is probably just bound up and needs to be freed.
 
What does the shock have to do with the driveline????:unsure:
Did I miss something?
A bent motor mount may have damaged the Pinion gear? Poor mesh now.
First remove the Power Module and a have look see. Needs to be frequently cleaned out anyway. Dirt builds up in there. Ruins the motor, pinion/spur, BB's and slipper assy.
But a motor that accelerates on its own is another issue altogether.
It is not clear what you are describing there. :unsure:
A video would help us to better help you.
 
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They don't necessarily have anything to do with it, but it may be a red herring - you could have an issue independent from the shock work.
 
Start at the motor and make sure it spins freely, disconnecting it from the spur and pulling the trigger. Then check the slipper and make sure it turns. Then check the front diff and make sure you can turn the wheels, and if you still can't turn the rear, time to pop open the diff and make sure all the gears can spin freely.

Something is probably just bound up and needs to be freed.
Thank you for the suggestions. Can you please inform me on where the spur is located to disconnect and what exactly is the slipper? Still learning the lingo. ;)
 
Make sure the center driveshaft doesn't have any rocks/stones caught/stuck in between it and the chassis..
Yeah, what Tex said - it seems something is stuck somewhere and you'll have to work your way through the drivetrain to figure it out. The center driveshaft is an easy thing to check so before you tear everything down, best to start with what's easy.
 
They don't necessarily have anything to do with it, but it may be a red herring - you could have an issue independent from the shock work.
Yes, it’s just extremely odd that these issues started immediately after I replaced shock arm. Seems coincidental.
 
Thank you for the suggestions. Can you please inform me on where the spur is located to disconnect and what exactly is the slipper? Still learning the lingo. ;)

The Spur is >
stock# = ARA311034


1668454133253.png
 
Yeah, what Tex said - it seems something is stuck somewhere and you'll have to work your way through the drivetrain to figure it out. The center driveshaft is an easy thing to check so before you tear everything down, best to start with what's easy.
Ok, I’ll start with the drivetrain. I already removed the driveshaft, check gear meshing, but something is still whining and the servo doesn’t move the wheels at all now. Very odd.
 
*************************

Center Driveshaft >
stock# = ARAC3955

1668454262030.png

.




********************

Ok, I’ll start with the drivetrain. I already removed the driveshaft, check gear meshing, but something is still whining and the servo doesn’t move the wheels at all now. Very odd.

What you might have is a some moisture could have gotten into your RX (receiver) or the connectors could have worked itself loose..

Double check your wires/connectors to make sure they are all seated properly.
 
What does the shock have to do with the driveline????:unsure:
Did I miss something?
A bent motor mount may have damaged the Pinion gear? Poor mesh now.
First remove the Power Module and a have look see. Needs to be frequently cleaned out anyway. Dirt builds up in there. Ruins the motor, pinion/spur, BB's and slipper assy.
But a motor that accelerates on its own is another issue altogether.
It is not clear what you are describing there. :unsure:
A video would help us to better help you.
When you say “power module” are you referring to the actual motor itself?
 
Well yeah, the whole plastic unit that the motor is attached to. It houses the slipper assy. and pinion/spur gears.
Refer to your manual or Arrmas website for instructions. Seems you never opened it up before, if you have to ask? :unsure: Get used to removing it. Where most issues arise from within.
Yeah it needs to be opened. Usually this is where you start. And where the problem usually lies, if it is not, then next you look over the front and rear diffs and driveline, with the P.M. still detached. The best way to detect any binding/ diff gear issues.
 
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When you say shock arm, are you talking about a lower a-arm? Post pictures of what you replaced and took apart.. also post pictures of it assembled as you have it...

There is an obvious bind some place in the driveline..
 
When you say “power module” are you referring to the actual motor itself?

stock# = ARA311032

The whole unit that the motor is mounted to is called the Power Module.


1668454644681.png
 
When you say “power module” are you referring to the actual motor itself?
What does the shock have to do with the driveline????:unsure:
Did I miss something?
A bent motor mount may have damaged the Pinion gear? Poor mesh now.
First remove the Power Module and a have look see. Needs to be frequently cleaned out anyway. Dirt builds up in there. Ruins the motor, pinion/spur, BB's and slipper assy.
But a motor that accelerates on its own is another issue altogether.
It is not clear what you are describing there. :unsure:
A video would help us to better help you.
I connected a fully charged 2s battery, powered the controller on, then powered on the BR. The wheels started spinning at full speed by themselves. I did not give it throttle. I immediately turned it off, then back on and it didn’t start going by itself again, however, it no longer responded to throttle or turning. I can hear the fans going and get the initial power on alert but no movement from servo, motor or wheels.
 
I connected a fully charged 2s battery, powered the controller on, then powered on the BR. The wheels started spinning at full speed by themselves. I did not give it throttle. I immediately turned it off, then back on and it didn’t start going by itself again, however, it no longer responded to throttle or turning. I can hear the fans going and get the initial power on alert but no movement from servo, motor or wheels.


Check your trim knobs on the radio.. make sure they are centered...
 
EFB48E95-D440-4637-B504-62116DC89121.jpeg
When you say shock arm, are you talking about a lower a-arm? Post pictures of what you replaced and took apart.. also post pictures of it assembled as you have it...

There is an obvious bind some place in the driveline..
The chrome piece broke off from the bottom black plastic piece. I replaced with a new chrome arm/leg/chrome piece that came attached already to the black piece/holder thingamagigy. 🤷🏽‍♂️
 
Did you go through water with your rig...? Did the ESC get wet??
 
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