First thing would be to check spur/pinion mesh like Tamiya Slave suggested. The Dyna Storm uses 0.4 module gears, so the mesh is much more difficult to set than most Tamiyas (that have 0.6 module). On the packages of 0.4 pinion sets, they suggest using a piece of plastic bag (thin plastic grocery bag I guess) between the gears to set mesh. You simply press the pinion hard against the spur with the plastic between them & tighten the motor screws. Then you just roll the plastic out from between the gears, and the running clearance should be just right. I remember doing this once and it worked well. I have since just used my eyes & ears to set the running clearance.
Also make sure the grub screw in the pinion hasn't come loose.
If the gears check out, the next thing would be to check the diff. Here's how:
- remove spur gear cover
- hold spur gear & nearest rear tire steady with one hand
- turn the other wheel with your other hand to make the drivetrain slip
- observe the adjuster nut on the end of the MDC during slip
- if the nut is turning while you hold the spur steady, your diff is good
- if the nut does not turn, you need to tighten or rebuild your diff.
Moral: The MDC should always slip well before the diff...
If the diff checks out good, the noise could be the clutch plates in the MDC are worn. You'll will have to remove the clutch housing cover & check them out. It's probably best to observe the correct order and direction that the 7 disc plates are in so you can put them back exactly how they were before. This will keep like surfaces matched up.
|