Pinion removal using common tools

This video demonstrates how to remove a pinion without using an actual pinion puller. The motor in this case is a Scorpion 2221-6 with a Rhino hardened steel pinion. When I installed this pinion, I used medium strength thread lock on the shaft as well as on the grub screw. I did this so I wouldn't have to worry about the pinion slipping during use. The drawback to this is that pinion removal will be extremely difficult to accomplish by hand.

What I did after removing the grub screw was use heat from a soldering iron to break the thread lock bond. After that I used needle nose pliers to get the pinion moving up the shaft slightly. As the gap between the pinion and the motor got larger, I filled the gap using hex drivers. This is done in order to provide a surface other than the motor to pry against, as well as to avoid any side loads on the motor shaft that would be made by prying at an angle.

Using larger tools as the pinion gets further up the shaft, eventually the pinion will reach the end where it will simply pop off or can be pulled off by hand. Using great care, this method is safe and will result in minimal or no damage to any components of the motor or the pinion.

Category:

Howto & Style

Tags:

• RC
• heli
• Align
• T-Rex
• 450
• Rhino
• Scorpion

[thybigballs]

What you did in your video is a big no-no. You are putting a lateral force on your bearings they are not designed to handle. This will damage them and is the reason pullers were invented.

[sheepdogMSP8117]

@thybigballs The whole point of the video was to show that you can remove a pinion even if you don't have a puller. If you do it carefully like I did, there won't be any problems. This motor has had several pinion changes using this method and not once was there a problem with the motor's shaft. Sure, it you pry it off in one swift move you're risking damage, but doing it little by little works fine.

[nts213]

Im having that problem i cant get the grub screw out it so tight i keep stripping my hex keys.

[sheepdogMSP8117]

You need to use a hex driver. It's like a screw driver but with a hex tip, usually hardened steel.  The regular allen wrenches are way too soft. Good luck.

[madcat303]

Awsome video, thanks

[sheepdogMSP8117]

Thanks madcat.

[Nelrockz1]

@garagecrap lol

[FJARVGR]

I worry about the axial load this places in the motor bearings. the gear puller solves a multitude of problems.

[leaman132]

nobody likes a bent shaft

[garagecrap]

That's easy but how can I remove pinion from factory pressed on motor? I tried it once using puller but puller broke. Than I tried blow torch, hammer etc and completely destroyed the motor but pinion still didn't move!

[jr9950]

Jesus. Talk about stringing it out. I could have said all of that in 30 seconds with enough description for anyone to do it properly. Save some bandwidth and make quick points when filming, please.

[Neur0nauT]

Nice vid.  Thanks for the tip!

[arsitama]

Is there a way to remove a pinion without grub screw using just common tools (not pinion puller) ?

[junior6273]

Hi, good video. What is the proper way to install a pinion?