Outcast Tired of blowing diffs with the XLX2 and 1100kv!

RCbuzz

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I haven't taken 6S apart, yet. Are they the same diffs, in the 8s, scaled up?
The 8S has huge spiral diff's, much bigger than the 6S, nice machining as well.
Honestly I wouldn’t expect much for $5… 🤷‍♂️

These big fat motors put out an immense amount of torque.
They are about 24$ after shipping. I kind of want to try one out! I just rebuilt my diff's though (stock plastic cups).

Then again, the HR cups are not that much more and sounds like they actually work, that is probably the route to go.
 
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Armarookie43

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Here we go. The front diff housing was still tight, after like 6 runs. But not the front. I ordered some new gears and a HR diff case. I like it better than the Arrma one since it's only open on one side. And it has the little pins to hold the diff gasket in place. The HR bolts are smaller, but it looks like quality. I used brake cleaner and red loctite. This one will go in the rear. I'll do like 6 runs and see what happens. Whish me luck!

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RCbuzz

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Looking good! What fluids you running? Do you have to use red on the grub screw too?
 

Armarookie43

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Looking good! What fluids you running? Do you have to use red on the grub screw too?
I used blue on the grub screw. What I didn't like about the grub screw is that it goes on there but it doesn't get tight, but it's not under pressure from the drivetrain. I'm going to try 1 million in the rear. I guess the 50k was too light.
 

SrC

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Looking good! What fluids you running? Do you have to use red on the grub screw too?
Grub does not need any Threadlocker applied. It is not under ANY load. It's just an access hole. And I never use Red TL on any RC rigs. Only Blue. Red is for fasteners that are 3/4" diameter and larger. And often is not removeable, even if heat is applied on these small fasteners. The hex heads usually strip out when you do. Even with known quality Hand drivers.
 
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Armarookie43

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Grub does not need any Threadlocker applied. It is not under ANY load. It's just an access hole. And I never use Red TL on any RC rigs. Only Blue. Red is for fasteners that are 3/4" diameter and larger. And often is not removeable, even if heat is applied on these small fasteners. The hex heads usually strip out when you do. Even with known quality Hand drivers.
No one told the CASTLE XLX2 and 1100kv motor that. It has loosened bolts with thread locker like putting a hit knife through butter. At least on the Arrma diff cases.
I tried that one too. It also came loose with the XLX2 and the Arrma diff cases.
 

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No one told the CASTLE XLX2 and 1100kv motor that. It has loosened bolts with thread locker like putting a hit knife through butter. At least on the Arrma diff cases.

I tried that one too. It also came loose with the XLX2 and the Arrma diff cases.
Not quite sure what you mean above????:unsure:

_________________________________________________

Having NO experience with 8s diffs, I can only say that with my 6s rigs, I use Loctite 243 (Blue)
It is Oil Tolerant. (y)
Reguar Blue 242 is not. FWIW.
And when building the diffs up, if ANY slightest amount of Diff Silicone Oil gets into the screw's 4 holes during the fill, No Threadlocker is going to cure properly at all. It is like using no TL at all. From experience. Whether using Red or Blue of any type TL. Most TL cures complete with 24 hours of non use after assy.
Need to use solvent to clean any screws and holes of oil, even if new. New screws tend to have a machining oil on them.
These 4 screws are under heavy loads. The biggest 8s user complaint is that the 4 screws just Shear off completely, and not necessarily loosening.(n) Ruined diffs.
If only the 1/5 Arrma rigs were 8 pounds lighter, this would solve many drivetrain issues.
This 30+ pound 1/5 rig can be a bear. You can't blame the electrics. It is just outputting power, what it is there to do.
 
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Armarookie43

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  5. Mojave EXB
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  7. Typhon 6s
Not quite sure what you mean above????:unsure:

_________________________________________________

Having NO experience with 8s diffs, I can only say that with my 6s rigs, I use Loctite 243 (Blue)
It is Oil Tolerant. (y)
Reguar Blue 242 is not. FWIW.
And when building the diffs up, if ANY slightest amount of Diff Silicone Oil gets into the screw's 4 holes during the fill, No Threadlocker is going to cure properly at all. It is like using no TL at all. From experience. Whether using Red or Blue of any type TL.
Need to use solvent to clean any screws and holes of oil, even if new. New screws tend to have a machining oil on them.
These 4 screws are under heavy loads. The biggest 8s user complaint is that the 4 screws shear off completely.(n) Ruined diffs.
If only the 1/5 Arrma rigs were 8 pounds lighter, this would solve many drivetrain issues.
This 30+ pound 1/5 rig can be a bear. You can't blame the electrics. It is just outputting power, what it is there to do.
In other words, I put a whole bunch of red loctite on the bolts for the aluminum Arrma diff cases and they always come loose after a few runs.
 

SrC

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This is always repeatable?
All I can say is that possibly:

- parts are not cleaned well enough in Solvent. (Chlorinated Brake Cleaner)
- Diff oil is getting into the holes threads/screws are touching diff oil upon filling/assy.
-You are not letting it cure for 24 hours before running the rig.

I follow this and never seen the screws loosen. (my 6s rigs).
But screws will always loosen if I don't follow this. Rushing it.
You can't rush the fill process getting even the slightest residue of Sil oil on the theads.
I sometimes use a tooth pick and introduce TL into the threaded holes as well as on the Screws, then assemble.
I use this one.
https://www.ebay.com/itm/3343793013...1291&msclkid=67a7a87e76c81bcddf8fcb05b4a7b53a

My gut feeling is that these alloy diff cups are too soft of an alloy, wearing out. The threads deform/getting rolled against the steel screws. So they can loosen easier the more and more they are wrenched.
Sometimes just replacing the screws with new, 4 on each side, and TL can help. WIll make them remain torqued. But at some point you need a new cup body.
 
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Armarookie43

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  2. Granite
  3. Infraction
  4. Kraton 8S
  5. Mojave EXB
  6. Outcast 8s
  7. Typhon 6s
This is always repeatable?
All I can say is that possibly:

- parts are not cleaned well enough in Solvent. (Chlorinated Brake Cleaner)
- Diff oil is getting into the holes threads/screws are touching diff oil upon filling/assy.
-You are not letting it cure for 24 hours before running the rig.

I follow this and never seen the screws loosen. (my 6s rigs).
But screws will always loosen if I don't follow this. Rushing it.
You can't rush the fill process getting even the slightest residue of Sil oil on the theads.
I sometimes use a tooth pick and introduce TL into the threaded holes as well as on the Screws, then assemble.
I use this one.
https://www.ebay.com/itm/3343793013...1291&msclkid=67a7a87e76c81bcddf8fcb05b4a7b53a

My gut feeling is that these alloy diff cups are too soft of an alloy, wearing out. The threads deform/getting rolled against the steel screws. So they can loosen easier the more and more they are wrenched.
Sometimes just replacing the screws with new, 4 on each side, and TL can help. WIll make them remain torqued. But at some point you need a new cup body.
Yeah it's pretty weird that it has happened so many times already. I'm going to wait at least 3 days, I'll be using brake cleaner, and I'll go from there. The aluminum used by Arrma leaves a lot to be desired, just like their so called 7075 chassis.
 

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There's a reason they call it Chinesium. Everything but the kitchen sink is used to make their "Alloys". All their garbage.
You have to wonder how they make their alloys for so cheap???:unsure:
It's really just all Monkey metal.:ROFLMAO: More like full of [email protected]#$%^&!
Like how Balogne is made.:rolleyes: And full of it.
 

Armarookie43

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  7. Typhon 6s
There's a reason they call it Chinesium. Everything but the kitchen sink is used to make their "Alloys". All their garbage.
You have to wonder how they make their alloys for so cheap???:unsure:
It's really just all Monkey metal.:ROFLMAO: More like full of [email protected]#$%^&!
Like how Balogne is made.:rolleyes: And full of it.
OK I followed your advice to not use red loctite this time. I loosened the screws again in all my diffs and cleaned everything up with brake cleaner and I used green loctite. It says it's resistant to oil too. I took my time in cleaning up the bolts and all that. I couldn't put back together the O8S because I lost one of the shims that go between the diff and the housing. Dammit. I told the hobby shop that there's no part number for that shim. But I think that he found it. He ordered some for stock. I'll see what happens with that. The stress worse case scenario would be to buy another difficult from Jenny's since they always come with that shim 🤦

20221121_161637.jpg
 

Moirae

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OK I followed your advice to not use red loctite this time. I loosened the screws again in all my diffs and cleaned everything up with brake cleaner and I used green loctite. It says it's resistant to oil too. I took my time in cleaning up the bolts and all that. I couldn't put back together the O8S because I lost one of the shims that go between the diff and the housing. Dammit. I told the hobby shop that there's no part number for that shim. But I think that he found it. He ordered some for stock. I'll see what happens with that. The stress worse case scenario would be to buy another difficult from Jenny's since they always come with that shim 🤦

View attachment 257778
https://www.horizonhobby.com/product/washer-20x24x0.2mm-4/ARA709054.html
talking about these? I was salty to realize my k8s and o8 didn't come with diff shims like all the 6s rigs do. I finally took my k8s diffs apart to troubleshoot a noise I've been having ever since I put in the 2028 lol. Noticed tons of side to side play and went looking in my old bag for the shims just assuming it came with some. :ROFLMAO: :ROFLMAO:
 

Armarookie43

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  1. Felony
  2. Granite
  3. Infraction
  4. Kraton 8S
  5. Mojave EXB
  6. Outcast 8s
  7. Typhon 6s
https://www.horizonhobby.com/product/washer-20x24x0.2mm-4/ARA709054.html
talking about these? I was salty to realize my k8s and o8 didn't come with diff shims like all the 6s rigs do. I finally took my k8s diffs apart to troubleshoot a noise I've been having ever since I put in the 2028 lol. Noticed tons of side to side play and went looking in my old bag for the shims just assuming it came with some. :ROFLMAO: :ROFLMAO:
Your rigs didn't come with those shims? I bought a V1.5 K8S an O8S and an EXB K8S and they all came with that shim. But I lost one 🤦. That's it I think. That's the shim that goes between the bearing and the diff housing right?
 

stock20

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This is always repeatable?
All I can say is that possibly:

- parts are not cleaned well enough in Solvent. (Chlorinated Brake Cleaner)
- Diff oil is getting into the holes threads/screws are touching diff oil upon filling/assy.
-You are not letting it cure for 24 hours before running the rig.

I follow this and never seen the screws loosen. (my 6s rigs).
But screws will always loosen if I don't follow this. Rushing it.
You can't rush the fill process getting even the slightest residue of Sil oil on the theads.
I sometimes use a tooth pick and introduce TL into the threaded holes as well as on the Screws, then assemble.
I use this one.
https://www.ebay.com/itm/3343793013...1291&msclkid=67a7a87e76c81bcddf8fcb05b4a7b53a

My gut feeling is that these alloy diff cups are too soft of an alloy, wearing out. The threads deform/getting rolled against the steel screws. So they can loosen easier the more and more they are wrenched.
Sometimes just replacing the screws with new, 4 on each side, and TL can help. WIll make them remain torqued. But at some point you need a new cup body.
A lot of great points here. Is there any trick to keeping the diff fluid out of the screw hole threads? A dumb question with obvious answer "don't over-fill", but out of fear of underfilling I always have a little fluid squeeze out when assembling. I used a tooth pick to remove from screw holes, but there's still some contamination. Maybe tape it up, assemble, wipe off excess, then reassemble?
 

Mirkdiggler

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Yeah it's pretty weird that it has happened so many times already. I'm going to wait at least 3 days, I'll be using brake cleaner, and I'll go from there. The aluminum used by Arrma leaves a lot to be desired, just like their so called 7075 chassis.
Bro, I hope the HR diff cases work for you. The shorter screws concern me, but those little posts may help and take some strain off the screw. Crossing my fingers for you.

What fluids are you using?
 

Armarookie43

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  2. Granite
  3. Infraction
  4. Kraton 8S
  5. Mojave EXB
  6. Outcast 8s
  7. Typhon 6s
Bro, I hope the HR diff cases work for you. The shorter screws concern me, but those little posts may help and take some strain off the screw. Crossing my fingers for you.

What fluids are you using?
Thanks. I did put punch control at 100%, so maybe that will help tame the XLX2 and 1100kv beast. I was even thinking about using the XLX2 with the smaller HW 1100KV motor if I still see trouble. I'm going to run 500k in the front and 1 million in the rear. It's mostly the rear that gives me trouble. Maybe it's my crazy driving, landing under power and using the huge 4.3 Pro-Line trenchers. The XLX2 generates like 12hp, so that's a lot of strain right there. I'll do another 5 runs and go from there. I'm also going to wait like a week so that the green loctite hardens as much as possible. If I see trouble, then I'll probably keep trying with maybe smaller lighter tires. I'm going to use the K8S this time as a test subject.
 
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