mikblue10

Hello, new to forum, new to rc cars. Bought a redcat volcano exp pro. Crashed it, still runs. Bent dogbone, shock shaft, front bumper. Ok did a few upgrades, aluminum chassis, new shocks, al. suspension arms, al. towers, new wheel axles, al steering hubs and a few others. Problem is when i put it all back together it would not run very good, kind of grinding, put back on plastic chassis and work great on pavement, but when i went into grass would not go. Any suggestion as to where to start. Thought about putting all plastic back on,

Thanks,, Mike

RustyUs

Hitting any high traction terrain will definitely find any weak spots in the driveline. No power to the wheels...sounds like grub/set screws came loose, and/or diff internals are very worn down and possibly needs shimming. Maybe hexes in the wheels are stripped?

mikblue10

Thank you, will take a look at all those things when i get a chance.

RustyUs

I'd start with the outside easy stuff first and work my way in.

• Wheels and their hexes
• Motor pinion gear set screw tight
• Pinion/spur gear mesh
• Universal Joint Cups (front/rear diffs) set screws tight
• Dogbones move freely when steering is at full left and right

If those all look good, then it's time to look at the diff gear internals, and inspect the teeth on all the gears.

As far as the aluminum arms go, I'd stick to the plastic ones. I would rather have a plastic arms snap, or break than have aluminum arms all bent up, and yanking on the chassis. It all depends on how hard you run your RCs as to how much rigidity you are willing to risk.

mikblue10

looked at all the components, they looked good to me,none of the gears seem to be worn, dogbones are good,set screw tight, even took diff apart and they looked good. Now that being said, I might not know what i am looking at. I am letting some else who has had rc cars in the past look at to see if I am missing something. Will get back when he lets me know if he finds anything(hope he does). Probably should have left the plastic on.

Thanks for your help

mikblue10

Sorry for the delay got the truck back,this afternoon, he said that the motor and pinion gear was slipping under pressure? Adjusted the motor a little. Did not help. Runs great on pavement, dirt and really short grass. Even runs good in tall (about 3") grass if I do not start off from a dead start. I can run slow, fast and even almost pop a wheelie in it. As long as i do not start off from a dead start in grass it runs great. It like there is no power when I go and try run it from grass. I can go give it a little bit of a shove then it goes ok. This was not like this when i bought the truck new (about it about a week or so ago). I am to point of putting all the plastic back on and see what happens. I made a statement that i took the diff apart, i only took the case apart. You guys are great and I hope I can get this resolved.
Thank you

Update, I took the driveshaft out making it a 2 wheel drive. No difference. Most of the time it moved on its on, a couple of times I had to give it a push. If I try to make it go and it doesn't ( I keep pulling trigger) it kicks out either the servo or the speed controller I believe. I shut it off and turn it back on and its ok. It does not make any sound or wierd noisies, Everthing is on the initial start, if starts moving everthing is good.

mikblue10

Started to take everthing apart. Have questions, doesn't the differential use oil? If so mine looked like grease, gears were hard to turn. If this is suppose to be oil why would it turn that thick so quick(truck is only about 2 weeks old. Also the cups looked a little bit worn. The drive gear doesn't look to good either, (order new ones). So I am going to replace both differnitals and drive gear and hope for the best, also put all plastic back on. The worst thing about this whole ordeal is that it probably has only a couple of hours of run time on it. Will keep posted after I get all the new parts in.

mikblue10

Update fixed problem, wheels were to tight, loosen them up just a little and it runs like new.