Senton Installed new diffs and have a question.

[Spruk]

I'm upgrading my sons Senton Mega 550 to 3S configuration. Part of that is switching out the diffs and pinion gears to the 3S versions. When I reassemble the diffs and pinions in the housing they aren't smooth, almost like they are catching on the housing. If I loosen the housing screws some they smooth out (Going from hand tight to a few turns loose). Is this OK? Any thoughts on what could be causing it? I did try shifting the side of the bearing the factory shim was on and removing the shim but that did not seem to change anything.

Second question, any advantage to upgrading to the aluminum diff holders?

Thanks

 

[pug]

Are your diff yokes damaged? Also, make sure the diff is seated right. If you have a V3, there is no need to upgrade the diffs since they are the same as the 3s V3.

 

[gotnitro]

If you have to loosen the diff housing screws to get it feeling smooth, you need to shim the diff properly from the gear teeth side. Shims would be installed next to the diff bearings. Advantages to aluminum diff housings, other than it being stronger, IMO no. Aluminum housings actually hold heat more than plastic. Diffs heat up more than the average RC'r knows.

 

[Spruk]

If you have to loosen the diff housing screws to get it feeling smooth, you need to shim the diff properly from the gear teeth side. Shims would be installed next to the diff bearings. Advantages to aluminum diff housings, other than it being stronger, IMO no. Aluminum housings actually hold heat more than plastic. Diffs heat up more than the average RC'r knows.

nitro, so I'm clear I need to add shims between the bearing and the diff on the side of the diff the gear teeth are pointing toward.

I should have some shims I can steal from his old diffs, I will give it a shot and advise. Otherwise I will do a search for the diff shim kit.

I had to upgrade the diffs and the pinons because he had a 2S Mega to start.

 

[pug]

nitro, so I'm clear I need to add shims between the bearing and the diff on the side of the diff the gear teeth are pointing toward.

I should have some shims I can steal from his old diffs, I will give it a shot and advise. Otherwise I will do a search for the diff shim kit.

I had to upgrade the diffs and the pinons because he had a 2S Mega to start.

The V3 Mega has the 3s diffs, I have a V3 mega that I’m running 3s on after a brushless conversion. If you have the V2 or V1, you need to upgrade them, what version do you have?

 

[gotnitro]

nitro, so I'm clear I need to add shims between the bearing and the diff on the side of the diff the gear teeth are pointing toward.

I should have some shims I can steal from his old diffs, I will give it a shot and advise. Otherwise I will do a search for the diff shim kit.

I had to upgrade the diffs and the pinons because he had a 2S Mega to start.

With everything lined up properly and tighten down correctly if you still get tension or grinding when you spin it by hand you will have to shim the ring gear away from the pinion so yes.

 

[Spruk]

gonitro - Thanks very much, that was it. I added two shims to the rear and its now nice and smooth. The front likely needs one more shim to be perfect.
last question, anyone know the correct part number on the shim set?

 

[FlipSide]

@gotnitro has a the best solution for you.

What I found on my Vorteks was that there was binding between the input gears and diffs with the diff yoke fully tight. As a temporary measure, I backed-out the diff yoke screws a *tiny* bit to get rid of the binding. After a few packs (like 2-3 packs iirc), the gears were bedded in and I could fully tighten the diff yokes without binding.

Certainly not as clean as proper shimming, but it worked for me.

YMMV

 

[Puddlejumpernva]

last question, anyone know the correct part number on the shim set?

Arrma Washer (4) (12x15.5x0.2mm)​

Part#: ARA709052