Back wheels not spinning?

[aaron11193]

Hey all, I'm new here and to nitro R/C, loving it so far

I have a HSP Tornado that my mum bought me for xmas, I'm learning more about these machines every day.
I've had about 2 things go wrong so far, both due to loose bolts/nuts, I learnt the hard way that RTRs arent put together very tightly I don't mind breaks too much because I enjoy working on my car .

Anyway my problem is, recently my back wheels stopped turning with the front wheels, as in they don't push the truck forward. I worked out that the hex bolt in the joint cup that goes from the dogbone to the rear diff had come loose so I tightened it, but it wouldn't run straight after that, the joint cup looks lopsided, like when it turns it leans to alternating sides.. poop it's hard to explain things in plain text.. so I held it straight with a screwdriver and tightened it up again, it ran relatively straight then, but after running it around for a while and going over my ramp a few times the rear wheels stopped turning again, I think something needs replacing but I don't know what..
Anyone got a clue?

Thanks, Aaron.

 

[syphon68]

Hi If you say it is misaligned in the drive cup you almost have to get up close and personal with it and turn it to see what is making it do that. Take stuff off if you need to but unfortunately that is the only way to sus it out. Take a close look also at the pin that goes into the drive cup to make sure that it didn't wear when it was loose causing it not to fit right, I know that the little pins on the end of the dog bone can wear and make it not fit correctly good luck....

 

[AmmoJammo]

can you post pics of it at all please?

 

[aaron11193]

Here is some pics:

Didn't have time to blast it with the air today.. is that a leaf?
That big gap isn't supposed to be there..

Oh very dirty :dumb:

 

[syphon68]

Is that grub screw tight on the shaft? it should seat into an flat spot or indentation on the output shaft I believe, and it could be that the grub screw is just turning around the shaft. be sure to use blue lock tite on these as they have a tendancy of coming loose which can round off the flat spot on the shaft.

 

[AmmoJammo]

but isn't that cup, with the grubscrew slid onto a hexagonal shaft?

 

[Metalhead Matt]

Just look at the other three that are still connected properly and do what you need to. If the shaft is metal, lock tite the grub screws. Use blue removable locktite.

 

[aaron11193]

Fixed it, see the difference?

The bearing was coming out so there was hardly any shaft to bolt onto

I'll get some loctite from work next time I go into town..

 

[AmmoJammo]

Fixed it, see the difference?

The bearing was coming out so there was hardly any shaft to bolt onto

I'll get some loctite from work next time I go into town..

looks the same to me..

the leaf is still there :

 

[Metalhead Matt]

Yeah, the bearings not about to fall out anymore.