Traxxas T-maxx wont move, no acceleration

[03area]

Hi guys, First post but hoping you can help
I have a Traxxas T-maxx 2.5 that will idle but when i put any throttle on it just revs but wont actually move anywhere. i have checked the clutch and there is no problem there, and there is also no problem with the spur gear either. Any insight will be helpful.

thanks in advance

 

[Rolex]

You need to tighten down the nut in the middle of the spur gear all the way. Then back it off 1/4 turn.

 

[03area]

Cheers will try that in the morning

Thanks for the rapid response i am very impressed will let u know if that helps

 

[Rolex]

The spur gear is also a 'slipper clutch' to take the shock out of the drive train when landing. If the engine revs, the spur gear spins, the slipper is the first suspect.
Keep us posted.

 

[03area]

It just strange how it has happened since i swapped then engine for a better engine (both stock) and the it wont move and i haven't been able to figure out what was wrong, so cheers for the help rolex

 

[KevinGalusha]

If you check those, and they are fine. Check the drive yolks coming out of the transmission and make sure the insides are not rounded out. The drive shaft out of the transmission is usually beveled, so you need to have some square shape inside the yolks.

 

[olds97_lss]

If you watch your rig without a body when it's running, what spins when you give it gas? Does the spur spin? Do any of the axles spin?

If it spins when your holding it in the air, but doesn't move the truck, watch it on the ground and see what is spinning vs what isn't. Between the two things you will find your issue.

Since you "swapped" out your engine, it makes me think maybe the flywheel nut is loose, your flywheel wasn't put on properly or your clutch wasn't properly assembled.

 

[jerry7007]

You need to tighten down the nut in the middle of the spur gear all the way. Then back it off 1/4 turn.

no rolex, your are not right, it is, tighten till strip then back-off a 1/4 turn. :

 

[03area]

Cheers guys for the help will try these later today and will let you know, thanks for all the ideas its appricicated

 

[03area]

Hi guys it seems that when i spin my spur wheel either way the wheels don't spin at all, the drive shafts spin when i turn the wheels but the spur doesn't does this mean it is something wrong inside the transmission?

 

[beason]

if the drive shafts are spinning then the trans is working. next would be to check the outdrives (from the diffs to the wheels) if they are not spinning, or only one end is spinning, then you have a diff problem. if they are spinning then you may have a stripped wheel.

 

[03area]

But the shafts only spin when i move the wheels, the spur gear doesn't move the wheels. so if i read this right then even if the spur gear doesn't move the wheels then it could still be the outdrives?

 

[marauder]

Start from the four corners and work your way in. Check all wheel nuts to see if any are loose. If they are tight, remove each wheel and examine your hex nuts and drive pins on the axle. Be sure the axle pin is installed properly through the axle and seated in the hex. Verify nothing is stripped out or rounded off, also note the hex inside the wheel where the hex nut seats, be sure that isn’t worn or rounded off as well.

Once you’ve eliminated those things, check your drive shafts coming from the front and rear differentials to each wheel. Are they broken/ damaged/ worn? If so, repair or replace those. If not, continue to your center drive. Again, are they broken/ damaged/ worn? If so, repair or replace accordingly. Check your slipper to ensure it is set as Rolex had noted, examine your slipper friction pad if it is worn, replace it. Be sure you have a proper gear mesh as well.

Differentials aren’t that difficult to take out, so you may want to check them while examining your driveline. Follow the manual for detailed explosion of how to disassemble and reassemble these key components. You’re looking for worn surfaces, broken gears, etc… Be sure to re-lube your differentials when reassembling.

Also, while we’re waiting, could you please tell us the events that led up to your truck not pulling under its own power? Did you install the clutch on the engine properly? The clutch bell? Did you land a jump with your finger hard on the throttle? Any information you can give would help us diagnose the problem faster. As much as we’d like to, we can’t come over and look at it ourselves.

Good luck, hope we can help you get back on the road.

 

[03area]

I was swapping the stock engine for another stock engine which had better compression, after i put that on i fired it up and drove around the back garden carefully checking everything was fine, then all of a sudden it just stopped driving and has been like this since, its really strange because nothing happened, and i was only driving it around on about 1/4 throttle so it wasn't anything stressful and it was only driving for about 2 minutes before it stopped driving.

 

[alpinehyperlite]

Might be a stripped hub.....

 

[03area]

Might be a stripped hub.....

What do you mean?

 

[marauder]

So when you give it throttle, the clutch bell on the engine spins, causing the spur gear to spin? It sounds to me like you may not have used loc-tite on your engine mount screws and they backed out causing the engine to walk away from the gear mesh. These engines are high rpm even at low idle, they'll rattle metal on metal screws out in a hurry. Check to be certain your mesh is still good, and that the clutch bell is spinning and in contact with the spur.

 

[03area]

alright i'll remount the engine, also do you know what the factory settings for the carb are? for some reason the slide wont open enough for it to stay running with out throttle trim, i already have the idle as high as it will go, i think the LSN may be to lean but i am not sure, cheers for the help guys sorry for all the trouble

 

[olds97_lss]

Usually if you have the idle adjustment cranked all the way in and it won't stay running, your LSN is way too rich. What engine is in it now? You said you swapped it, so giving you mfr settings is kind of hard when we don't know the engine your running.

The original t-maxx 2.5 with reverse has the trans symptoms your talking about. The spur will spin freely in either direction until the RPM get up a bit and engage a clutch inside the trans. It's what causes the lurching when your driving slow.

 

[03area]

Then engine that has been swapped is a stock tmaxx 2.5 engine, the only difference between the old and neww one is better compressions and a larger cooling head, but this one want staying running its, as if the needles are wrong.

yes it is a standard 2.5 with the reverse, but i never noticed any lurching when i was driving slow.