Having found a broken fuse, I thought that might be all it was.
Having dug a little deeper, and in the process removed the tracks, I found there was an odd noise coming from the sprocket, once per revolution.
I removed the motor, and found that was nice and smooth, but the sprocket had a couple of obvious sticking points.
Next off, I removed the sprocket - which was loose on the taper lock - and then the final drive housing.
This is the state of the main drive gear:
When I first saw it, I though someone had skimmed the gear to prevent the teeth from hitting the hull.
Then I noticed the teeth were higher as well.
The reason for this groove ? Check out the cap head bolt in the centre of this picture:
It is working its way out of the motor mount and, because it is a toughened bolt, it is wearing a groove in the main drive gear.
So now I need to strip down the other side and see if the same is happening there.
When they go back in, I'll be adding some Loctite to ensure they stay in position.
Adrian.
