Big Rock ARRMA BIG ROCK PROBLEM PLEASE HELP!!

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GursevekRcGuy

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Hey guys I’m having a issue with my big rock, when I try to drive it makes kinda a high pitch sound like it’s just the motor spinning. It’s not the spur gear, it’s not striped and the mesh seems fine. The pinion gear is fine also. To me the diffs seem fine. I have a video on it and please watch it:
Thanks-singh
 
It sounds exactly like a loose slipper clutch that needs to be tightened. It could even need reassembling. There's also a chance that the pinion gear is loose on the motor shaft but it's much more likely the former
 
It sounds exactly like a loose slipper clutch that needs to be tightened. It could even need reassembling. There's also a chance that the pinion gear is loose on the motor shaft but it's much more likely the former
yea I’m pretty sure your right. I tightened it and worked perfect but after 2 min it became loose agian. Should I put locktite on the on the screw?The screw is in the silver part.

image.jpg
 
yea I’m pretty sure your right. I tightened it and worked perfect but after 2 min it became loose agian. Should I put locktite on the on the screw?The screw is in the silver part.

View attachment 191575
Pull the spur/slipper assembly out first - don't take out the adjustment screw before you do, or the components of the slipper assembly could come out of line

Follow YT guides and take note of how it went together when disassembling it. There's always the exploded view on Arrma's website. It will come apart when you take out the adjustment screw. Don't lose the thrust bearing and spring!

You'll only need to add a dab of blue thread lock on the adjustment screw around 1/4 or maybe a 1/3 from the tip when reassembling it. The tip of the screw will be going in to the plastic nut at the end of the slipper, so you shouldn't thread lock the tip

Then follow this method on how to best adjust the clutch. FYI, you may not need to follow the thread lock procedure in the video because the newer clutches (your own) include the plastic lock nut:

 
@Yas has you sorted for sure...👍

I will only add, make sure you let any thread lock you use sit 24hrs before being put back into service..👍
 
If you have a newer Arrma 3s, they use a plastic nut to hold the slipper screw in place. However, the plastic nut can loosen/strip, which is most likely what happened to you. Older versions did not use the plastic nut and required loc-tite.

There are two possible solutions:
1) loc-tite the screw as recommended by Yas. However, the newer 3s Arrma's changed to a plastic nut because many people (like me) had a problem with the slipper screw coming loose even when using loc-tite.
2) get a new slipper maintenance kit https://www.arrma-rc.com/part/ARA311033
It will include a new plastic nut. I find the plastic nut strips if you adjust your slipper too often. After some trial and error, I know exactly how tight I like my slipper now, so I can set it once and not touch it again. So far, the plastic nut is holding. If you want to use the plastic nut instead of loc-tite, try not to adjust it too much after installing a new one.

Neither option is perfect. I prefer the plastic nut. However, I would try loc-tite first. If it holds, no reason to buy a new slipper maintenance kit. If you want to use the plastic nut instead, you should have a good idea of how tight you like your slipper before installing a new one.
 
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If you have a newer Arrma 3s, they use a plastic nut to hold the slipper screw in place. However, the plastic nut can loosen/strip, which is most likely what happened to you. Older versions did not use the plastic nut and required loc-tite.

There are two possible solutions:
1) loc-tite the screw as recommended by Yas. However, the newer 3s Arrma's changed to a plastic nut because many people (like me) had a problem with the slipper screw coming loose even when using loc-tite.
2) get a new slipper maintenance kit https://www.arrma-rc.com/part/ARA311033
It will include a new plastic nut. I find the plastic nut strips if you adjust your slipper too often. After some trial and error, I know exactly how tight I like my slipper now, so I can set it once and not touch it again. So far, the plastic nut is holding. If you want to use the plastic nut instead of loc-tite, try not to adjust it too much after installing a new one.

Neither option is perfect. I prefer the plastic nut. However, I would try loc-tite first. If it holds, no reason to buy a new slipper maintenance kit. If you want to use the plastic nut instead, you should have a good idea of how tight you like your slipper before installing a new one.

Good post Man...

I had problems with the plastic nut with the brass insert. So I switched over to the all-plastic nut. BUT it was from an older (spare) 3S slipper that had never been adjusted but the slipper had zero issues and worked great. So the first time the nut was touched was when I took it out and reassembled it...so that made one full cycle unloosen and tighten on that plastic nut.

I do have a new kit on standby if I need to go with the new nut I do not want to use TL.

Question. Glad this is working for you but I'd like to know how did you tighten your slipper. I have not gotten a chance to test this due to winter weather what I posted above for the maiden test....what I did was:

Followed JonDilly posted method using a hex wrench and rolling it until the tires dragged. I stopped and I did not use TL and assembled it all back. Waiting to test hoping it does not come loose.

Did you do yours this way? Or did you hand tighten? If you hand tighten, how much did you tighten it (I see may YT break the slipper getting it super tight where it pops and then back-off)? If you did back-off once tight to however you tighten it, how many turns did you back off if any?

Thx Man!
 
JonDilly's method will make sure you don't overtighten. But in my opinion results in a fully tightened slipper. Which is fine if you want to run that way. A tight slipper is more responsive, wheelies much more easily, backflips faster. But it also has drawbacks, like driveshafts popping more easily and excessive wheelies. (Which are very bad when accelerating into a ramp.)

I manually screw in my slipper, then loosen it just under 1-1/2 turns. I think it's easy not to overtighten. The screw spins easily. Once you meet that initial resistance, it's fully tight. STOP and do not overtighten. I've tested it. The wheel skid method and manually screwing it until you meet resistance is the same point. Which makes sense, since the wheels start skidding once they meet resistance. You can also use JonDilly's wheel skid method, then loosen by rolling backwards. But since I know the exact amount I like to loosen, I find I can be more precise by doing it manually.

How much you want to loosen is very much personal preference. For me, just under 1-1/2 turns is the best balance of preserving driveshafts, avoiding wheelies when ramp jumping and maintaining a good flip speed.
 
Hey guys I’m having a issue with my big rock, when I try to drive it makes kinda a high pitch sound like it’s just the motor spinning. It’s not the spur gear, it’s not striped and the mesh seems fine. The pinion gear is fine also. To me the diffs seem fine. I have a video on it and please watch it:
Thanks-singh
Hi Guys, I’m a newbie here and experiencing this issue too. Ie: Whining noise when accelerating with Transmitter. I let my wife bash a little with it and she said it hit a Concrete Structure. Lol. I will post a vid here if I can figure out how to do it. Lol. And, attempt to debug the issue. The weather is warming up and ice and snow melting. Anxious to get her running again. More later….
 
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