Typhon What did I do wrong? Shredded pinion with steel spur

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

clone2002

Fairly New Member
Messages
19
Reaction score
6
Hi all, I have a Typhon 3s (but this is probably applicable to all the 4x4 3s models).
TL;DR is that my stock pinion is DESTROYED after tightening it and with a steel spur gear.

Longer version:
Recently got the Steel 57T spur gear assembly. I slightly loosened the slipper clutch screw even though it’s supposed to come pre-set but figured just in case. Ran it a few times and things seemed ok. I disassembled the car yesterday to fix something and checked on the pinion and spur gear. Noticed 1 small chip in the pinion and then also noticed that it seemed a bit loose so I put thread lock on the small set screw and tightened it all the way. I wasn’t sure how far to push it toward the motor but went by where i saw a mark already. It seemed ok and definitely set in place. Reassemble the car and took it out today and within 2 minutes heard metallic grinding. So that was the end of my bash session sadly. Got home and took a look. The pinion is destroyed. Spur gear looks perfect though. What did I do wrong?

Is there a better pinion? Was I not supposed to over tighten it? Did I push the pinion in too far toward the motor? Did a pebble or dirt just get in? How do I avoid this happening again?

Thank you!
Adding photo!

442ACB6C-BCFC-4190-9BDE-1D4624C07EAC.jpeg


image.jpg
 
Last edited:
Just out of curiosity does your motor still spin? And is there any side to side play in the motor shaft?
Do you mean the bearings on the spur gear? Both relatively new fast eddy sealed bearings.
No inside the motor.
 
Just out of curiosity does your motor still spin? And is there any side to side play in the motor shaft?

No inside the motor.
Motor spins. Don’t feel any side to side movements. And I had just tightened the motor mount.
 
Just out of curiosity does your motor still spin? And is there any side to side play in the motor shaft?

No inside the motor.
Will check. Have never opened up the motor!
Will check. Have never opened up the motor!
Noticing now that one motor screw is missing...
Will check. Have never opened up the motor!

Noticing now that one motor screw is missing...
And inside I can move the shaft side to side a little...
Will check. Have never opened up the motor!

Noticing now that one motor screw is missing...

And inside I can move the shaft side to side a little...
Could the shaft be bent somehow?
 
Last edited:
If you can move the shaft of the motor side to side the bearing has failed.. and there is your failure..
 
Made a short video to show you what’s happening. Thank you all for the help!
 
Yeah the front bearing is fubar, there should be zero side to side movement of the motor shaft, a little in and out is normal. And that washer is supposed to look like that, it is a spring washer irrc.
 
Yeah the front bearing is fubar, there should be zero side to side movement of the motor shaft, a little in and out is normal. And that washer is supposed to look like that, it is a spring washer irrc.
So even that minute movement in the front is enough? Also just put up another video running the motor.
 
Here's what my pinion looked like right before I noticed bearing by shaft in motor went out.very common in 3660 motors.these are the replacement bearings I used

Screenshot_20200719-041926_Photos.jpg


Screenshot_20200815-180300_Amazon Shopping.jpg
 
Wrote into Arrma and they’re sending me a replacement motor and pinion. Will also try to fix this one.
 
I've replaced bearings in 2 of them 1 took the one size an other took different ones.appeartly they used 2 diff sizes.
 
Old Thread: Hello . There have been no replies in this thread for 90 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top