Trucks Problem with my T-Maxx

[fishkillbill]

Someone gave me a T-Maxx 2.5 truck. I got the motor running, but the wheels won't go around. I'm new to trucks. I've been flying RC planes for many years. Can anyone tell me if it is something simple, or do I have to tear the transmission apart?

 

[Tony]

First thing I would check is the clutches on the engine. From there, check all of the gears inside the trans and make sure the dog is swinging out on the input gear inside the trans. If it is not, either clean it really good and apply fresh silicone grease, or replace it. But it is normal for the spur to spin free, this is what allows reverse in these Rc cars. But when you rev the engine up, it should slam into gear, literally.

As for the forward reverse being enough, you will be able to find that out when you get it moving under its own power. But that may be one of the issues. There may be a stripped gear inside the trans. They are all plastic in there so it's likely if it wasn't taken care of.

 

[fishkillbill]

Thanks for the reply. I looked at the centrifugal force thing on the motor shaft. The one with the spring around it, looked OK. I assume if that wasn't right, the spar gear wouldn't spin. Maybe I never revved the motor up real fast for the clutch inside the transmission to fly out and engage. What does the nut on the spar gear do? Besides hold it on?

 

[Tony]

It is a slipper clutch. If you take the nut and spring off, you will see that the spur is being sandwiched between two disks. This allows teh spur to slip slightly to avoid transmission damage due to over torque situations. It also helps with traction.

And what you were looking at was the clutch shoes inside the clutch bell on the engine. If it has a spring around it, it is more than likely an aftermarket RPM brand clutch which is very good. The clutch I was talking about though is inside the transmission.

 

[fishkillbill]

I got it running. First it would only go in reverse. I took the transmission apart and sure enough, that "dog" thing was stuck. I cleaned it up and now it goes forward and reverse. It's just that it's jerking. Would anyone have any suggestions what could be causing it?

 

[Tony]

That engine sounds very lean. And I see no smoke coming from it which is a bad thing. That lunging is normal under part throttle acceleration. I would set your needles to factory, top and bottom, and lean the top out about 3 hours and see what that does.