Quote:
Originally Posted by adey
That's very odd. Is it possible that the grease you are using is drying up in the gearbox ?. Is the transmission free spinning when built ?. Others on here may disagree but I doubt much dust would get in gearbox from racing if if it did I would expect it to take a while. For me it's either a gear binding on the Gbox, binding on each other or the grease.
|
The transmission rotated really freely. Spinning the wheels, it ran on for ages (with no pinion).
I'd just applied a very small amount of silicon grease to the layshaft gear and idler gear, which was worked in. Only a tiny amount, it almost disappeared when worked in rotating the box before assembly. It wasn't packed with grease, and there was no grease binding the tranny.
I've left it totally dry this time i've rebuilt.
There was some wear to the idler gear teeth, and less wear to the diff gear teeth. I'm guessing the idler gear wears more as its in contact with the metal layshaft gear.
The four small bearings were all free of dirt internally and span freely. One outdrive bearing was free, the other was rough and didn't spin freely.
It ran for four meetings, two on carpet, two outdoors/grass/astro.
I've now rebuilt it, replacing the diff and idler gears, and all bearings as I had spares.
I do wonder if dirt passes into the transmission either through the bottom square in the casing that's exposed in the rear arm mount/chassis plate, or passing either through the outdrive bearings, or through the bearing seats of the outdrives. Another thought is through slipper dust through the bearing seat of the top layshaft. I wonder if a shim kit would take out any slop, or that small side to side movement of the diff and layshaft, preventing any dirt pass through? it's just a theory, but i'm puzzled as to where else it come from.