[Cameo]

Hang on a minute do nothing else until you read this.

1. The idler gear is like a suicide gear for the gearbox. It's the part that breaks when something is wrong as it’s the cheapest part. Like all metal gear servos have one plastic gear in case something goes wrong

2. My educated guess is the gearbox suffered to much stress and the idler gave up. Possible causes could be
a. The grass was quite long and this caused the car to work really hard to get through it.
b. The slipper is not tight enough causing excess heat build up and melting the idler.
c. both of the above occurred.

3. When you rebuild do the following steps
a. compress the diff and slipper spring (with a set of pliers just fully compress the spring 3-4 times)
b. rebuild the diff, tighten the diff screw to full then loosed off 1/4 of a turn.
c. clean all the diff gears with electrical parts cleaner and toothbrush - do not put any lube back on the gears. (Just inside the diff as the manual suggests)
d. rebuild the slipper and tighten so it has 1mm of thread showing past the lock nut (tighter than you had it)
e. DON'T drive it in long grass where you could stress the gear box out or you will simply break another idler.

Note - HPI do an idler for their Short Course Truck (Blitz) it fits perfectly into this car and is made of a more resilient plastic