Dex410 Noisy when pulling away

[neilma1]

Hi Folks,

I picked up a new Durango DEX410RV3 this week and have just finished building it tonight (put a Turnigy 80A Trackstar Waterproof ESC in with a Turnigy Trackstar 5200Kv motor (21 Pinion gear)

All seems fine except for initial pulling away - I get this rapid knocking sound (something like a jackhammer (but 1/10 scale ) for the first meter or so, then its fine. If the car is rolling and you accelerate, you don't hear the sound. If I pick the car up and accelerate hard, no sound. Its only when its on the ground.

I thought it could be the slipper clutch however the only video I can find on youtube that has the sound on it, makes more of a whoosh sound when it slips.

The motor looks meshed against the spur gear (and not slipping) so I am at a loss what it could be.

I have found that I have installed my diffs upside down in the car, but I don't suppose that makes that much difference but will swap them back tomorrow morning.

Any ideas?

Thanks!

[Legacy555]

Difficult to say without seeing the car. But sounds like the rear diff isn't shimmed correctly. Check the manual

[Jason A]

Hi,

Maybe have a look to see if the screws that hold the motor in are not touching against the pinion.

Thanks

[neilma1]

Thanks guys - I will pull the diffs tonight (turn them the right way) and then check them over.

The motor mount screws aren't touching the gears. Although if they were I would assume I'd get the noise all of the time rather than just for the initial second or so of acceleration from a standing start?

[mattr]

I had it when my diff wasn't shimmed correctly. The gears can slip under high loads. I got it under heavy braking too.
Also check the outdrive bearings are seated in the diff case correctly, this can cause the same symptoms.

[drobec]

Sorry for OT but: Are you sure you have diffs wrong way? If they're upside down car would go backwards. Rear diff can go in only one way (there's a cutaway in plastic part on bottom on chassis to make diff easier to slip in) and front diff have to go in according to rear diff because it would turn opposite way (backwards) if inserted wrong. Check in manual how they should go in, there's only one way for them to work properly (go forward).

[neilma1]

Well I am not sure So according to the manual and from what I have found elsewhere, the screwheads should be on the bottom.

However I have managed to fit mine in with the screwheads on the top (on the front and rear)

As for them running forward or backwards, I guess with the brushless motor I can just change 2 of the wires to make the motor spin the other way so it doesn't really matter which way they go?