Broken center diff repair.

[Jimbobjr]

Seems like most are breaking the silver screws off in their diffs. I heated mine up with a torch and still broke two off. If you manage to get one side off with no damage there’s a pretty easy fix. First you need to take pictures and call horizon for a new housing or whole new diff.

After they confirm they are sending you a new one (this is their fault, so it’s not like I’m ripping them off...) you will want the broken one for a spare or different diff set up so here’s what you do.
1) take the diff apart and get the housing nice and clean so debris don’t stick to it.
2) get a #33 (.113”) drill and put it in your drill press. If you don’t have one (drill press) and you are an adult male you should go and buy one...
3) carefully set the housing on the good side and drill through the good holes to the other side.
4) you will need either a 6-40 or the m3.5 tap (with matching bolts) turn the housing over and tap a thread or two by hand with the tap in the drill press chuck. This will assure it to be nice and straight.
5) now just tap them to depth by hand.
6) reassemble the diff.

Did this today and all seems fine. I used 6-40 screws because I have them in abundance. You can get a tap on amazon pretty cheap. You could probably find a 6-32 at Home Depot but 6-40 is nearly the same a m3.5.
I used 2.5mil diff fluid with some thin slivers of silicon ear plug.

 

[olds97_lss]

2) get a #33 (.113”) drill and put it in your drill press. If you don’t have one (drill press) and you are an adult male you should go and buy one...

That cracks me up! I have had a use for one at least 20 times, but really lack the space, since my RC room is also my office and is wall to wall "stuff" that I need and use every day. I just don't have a spare 12-18" of space for one.

Does that gear just sit on the outer edge of the diff or is there something that holds it on that's not pictured?

 

[Jimbobjr]

That cracks me up! I have had a use for one at least 20 times, but really lack the space, since my RC room is also my office and is wall to wall "stuff" that I need and use every day. I just don't have a spare 12-18" of space for one.

Does that gear just sit on the outer edge of the diff or is there something that holds it on that's not pictured?

The gear has a spine that matches the housing. It is captivated by the dif cap ends and has 3 little spacers to push it tight to one side.

 

[gotnitro]

Very NICE jimbob!

 

[gotnitro]

I used 2.5mil diff fluid with some thin slivers of silicon ear plug.

Have you had a chance to run it yet? Curious to know how the ear plug slivers are doing. Mine is still unloading on the front a little with 20M, more than I'd like. Was thinking about doing that if its working.

 

[Jimbobjr]

Have you had a chance to run it yet? Curious to know how the ear plug slivers are doing. Mine is still unloading on the front a little with 20M, more than I'd like. Was thinking about doing that if its working.

I haven’t run it yet. Even with the ear plug pieces in there it still turns but is stiff. Unfortunately my k8s will be a part for a while longer. The ear plugs are 6$ at cvs so much cheaper than diff fluid. I filled it best I could with the 2.5 mil and added the earplug pieces right on top of the sun gears.

 

[gotnitro]

I haven’t run it yet. Even with the ear plug pieces in there it still turns but is stiff. Unfortunately my k8s will be a part for a while longer. The ear plugs are 6$ at cvs so much cheaper than diff fluid. I filled it best I could with the 2.5 mil and added the earplug pieces right on top of the sun gears.

I have a couple bags of 3M plugs, I use them in my ears lol. Vance and Hines Harley off road pipe is too loud even behind me. Doesn't help the tinnitus. Too many Pantera concerts in the late 80's early 90's.. Gota love getting older..

 

[jondilly1974]

I have a couple bags of 3M plugs, I use them in my ears lol. Vance and Hines Harley off road pipe is too loud even behind me. Doesn't help the tinnitus. Too many Pantera concerts in the late 80's early 90's.. Gota love getting older..

I saw Pantera in the early 90’s. ??

 

[Jimbobjr]

Idk what the 3m ones are made of but you want the silicon ones. They can be easily formed into any shape. Kind of like putty. CVS brand and a company called Mack's makes them.

 

[gotnitro]

Idk what the 3m ones are made of but you want the silicon ones. They can be easily formed into any shape. Kind of like putty. CVS brand and a company called Mack's makes them.

Oh that thick .. Yeah Yeah! I know what you mean now.

 

[Arrma15T68]

I have a couple bags of 3M plugs, I use them in my ears lol. Vance and Hines Harley off road pipe is too loud even behind me. Doesn't help the tinnitus. Too many Pantera concerts in the late 80's early 90's.. Gota love getting older..

Lol,Good for you man !

 

[Dosx82]

Hello everyone
I just want to say thank you to everyone on this forum lots of great info on here
I know this is an old thread, however I was wondering if anyone has had this issue
I filled my K8S with 20mil put it back together after a test run I noticed that the truck would instantly flip on its back
Went back in to take a look and realized one of the sides of the diff had 2 broken screw heads literally popped of from the extra force so the center diff had locked up somehow

anyhow has anyone else had issues with the screw heads breaking off from the forces created by the 20mil grease and moving gears?

the screws did not break when I first disassembled the center diff

thanks
Dos

 

[Dosx82]

Hi everyone
I just want to say thank you to everyone on this forum lots of great info on here
I know this is an old thread, however I was wondering if anyone has had this issue
I filled my K8S with 20mil put it back together after a test run I noticed that the truck would instantly flip on its back
Went back in to take a look and realized one of the sides of the diff had 2 broken screw heads literally popped of from the extra force so the center diff had locked up somehow

anyhow has anyone else had issues with the screw heads breaking off from the forces created by the 20mil grease and moving gears?

the screws did not break when I first disassembled the center diff

thanks
Dos
This is my first arrma rc and I love the beast it’s amazing even on stock electronics I have done some upgrades as follows
Primal rc steering servo
Rear HR hubs saving $ for the fronts
Rpm front upper and lower a arms
( I broke 3 stock so decided to go with rpm)
20mil in center diff
Proline mx43 badlands
Waiting to order mamba xlx 2 1100kv amain doesn’t have any in stock atm
Again i just want to say thank you to everyone on this here forum so much knowledge and tips and tricks to learn
Thanks again everyone

 

[SentFlying]

Hi everyone
I just want to say thank you to everyone on this forum lots of great info on here
I know this is an old thread, however I was wondering if anyone has had this issue
I filled my K8S with 20mil put it back together after a test run I noticed that the truck would instantly flip on its back
Went back in to take a look and realized one of the sides of the diff had 2 broken screw heads literally popped of from the extra force so the center diff had locked up somehow

anyhow has anyone else had issues with the screw heads breaking off from the forces created by the 20mil grease and moving gears?

the screws did not break when I first disassembled the center diff

thanks
Dos
This is my first arrma rc and I love the beast it’s amazing even on stock electronics I have done some upgrades as follows
Primal rc steering servo
Rear HR hubs saving $ for the fronts
Rpm front upper and lower a arms
( I broke 3 stock so decided to go with rpm)
20mil in center diff
Proline mx43 badlands
Waiting to order mamba xlx 2 1100kv amain doesn’t have any in stock atm
Again i just want to say thank you to everyone on this here forum so much knowledge and tips and tricks to learn
Thanks again everyone

Start a build thread???

 

[Dosx82]

Start a build thread???

What’s a build thread sorry for the stupid question lol

 

[Dosx82]

Got my just bash it 7075 chassis for the k8s here some pictures looks freaking awesome

 

[RATT]

I have a couple bags of 3M plugs, I use them in my ears lol. Vance and Hines Harley off road pipe is too loud even behind me. Doesn't help the tinnitus. Too many Pantera concerts in the late 80's early 90's.. Gota love getting older..

Me and you both. To many pantera concerts indeed. May i ask why the earplugs are needed? Haha

 

[gotnitro]

Me and you both. To many pantera concerts indeed. May i ask why the earplugs are needed? Haha

They are cheaper than buying 20M fluid for the center diff. Not the foam plugs, the sticky clear plugs.

 

[RATT]

They are cheaper than buying 20M fluid for the center diff. Not the foam plugs, the sticky clear plugs.

Man, i have not done that trick. Could you walk me through on how to save money using plugs. This, has really grabbed my interest.
So, i am guessing melt them and put in the differential. Sounds like about 20 minutes of work. That would be the same consistency as some of the diff glue i have seen. Do you cut in any other chem to soften it?

 

[gotnitro]

Man, i have not done that trick. Could you walk me through on how to save money using plugs. This, has really grabbed my interest.
So, i am guessing melt them and put in the differential. Sounds like about 20 minutes of work. That would be the same consistency as some of the diff glue i have seen. Do you cut in any other chem to soften it?

I never used them. I used 20M fluid in mine and it works out perfectly.