TRX 3.3 Problems

[Jump To:]

Jump To:

-Arcade -The Hang Out -Comedy Spot -Other Interests -Monster Trucks -Stadium Trucks -Buggy board -On-Road -Giant Scale -Mini's & Micro's -R/C Off Topic -Photo Spot -Video Vault -Tip and Tricks -Nitro Engines -Trouble Shooting -Electronics -Clasifieds --eBay White List --Feedback -Forum Support

11 Guests, 6 Users, 0 Users in Chat
bmack, FarknBen, Explosive Racing, Gator, DeadManInc, SupaMan

18mt

mrn8's MGT #2

[Gator]

Hey guys, I have a strange problem I hope you can help with. I picked up my Step-Son's 3.3 Revo to bring home to work on for him. He just replaced the piston/sleeve and he said it wouldn't run right. I found the OWB in backwards, reverse gear stripped, and body mounts needing replaced. I also found an air leak in the tank cap, replaced the wiring harness, and new green/tan shock springs/shock oil...

After fixing all that, I couldn't get it to idle... It would run, but stall if letting off the throttle. I dropped it off at Barry's house to have him look at it. He found by increasing the throttle rate on the TX he could get it to idle... BUT the carb slide is half way open for it to idle correctly, not the usual couple millimeters. What could be causing that? Could there be some crap in the carb? Any ideas would be greatly appreciated!

Thanks,

Terry



edit:
Also... If anyone has a used carb for sale, I would be interested.

[jombo]

oldschool had the same problem with his tmaxx and after the engine died, i still cant figure that one out. on the sts i had after taking it apart because of a high idle it had particles inbetween the rear bearing and the drive shaft , it couldnt hurt to look 

edit : between the carb intake and the rear bearing

[docphysics]

yea, it sounds like a classic loss of compression issue.   But you said it has a new p/s.    So.....   I assume you put in a new glow plug?   Head shims installed?   Was the piston installed in the correct direction (i.e. not rotated 180 degrees)

Did you do a leak test on the tank, fuel lines?    Permatex the carb and backplate?   Using fresh nitro? That's about all I can think of........     

[docphysics]

Any luck?

[Gator]

yea, it sounds like a classic loss of compression issue.   But you said it has a new p/s.  Yes  So.....   I assume you put in a new glow plug?  Yes I did  Head shims installed? Not sure?  Was the piston installed in the correct direction Not sure? (i.e. not rotated 180 degrees)

Did you do a leak test on the tank, fuel lines?  Yes, No leaks!   Permatex the carb and backplate?  No   Using fresh nitro? No, but it runs fine in my other trucks..That's about all I can think of........     

Thanks Karl!  Barry said he was able to get a few heat cycles through it...  He said the HSN tip is flat, maybe that could be it?  I have another needle to try once I get it back.

Jombo:  I'm going to pull the motor and check the carb and intake, thanks!

[madmax22]

i got a carb you can buy, its off a 2.5 but i think it will still work LMK.

[SupaMan]

whatever it is its down to the carb and or linkage. i got 5 cycles total threw it today without using the brakes because as soon as you touch them it kills the engine.

if you leave the radio at normal throttle trim and adjust the high speed needle while trying to fire the engine you can hear it try to start but it never does completely fire so im pretty sure that needle needs to be changed.

other than that the motor runs GREAT!

[Gator]

i got a carb you can buy, its off a 2.5 but i think it will still work LMK.

Cool Max!   

Its the same carb according to Tower...  Pics please!  How much shipped to 33976?

[Gator]

Thanks Barry!    I found the other needles, so I'll give it a shot! 

[SupaMan]

tomorrow if im not busy ima try and mess with the linkage and get it to open the carb 100% we found today that its only openin like 85-90%

but just as a reminder this engine has a total of 6 cycles on it now.

[Gator]

Cool!  I appreciate your help!   I have to go Christmas shopping today...    I'll bring the other needle with me in case I'm close to the Cape. 

[Explosive Racing]

Hey, just found this thread.  Alot happens when I go down south.  Oh well

Anyways, you get it work properly again?  Any info?

[madmax22]

I just sent gator a hardly used carb used maybe 5-6 times?

[SupaMan]

I couldnt get the truck running unless the carb was halfway open but when you hold the ez start button and play with the high end needle (turning it leaner slowly) you can hear the truck want to fire so im pretty sure that needle is leaking.

He picked it up today from my house its supposed to be going back to its owner tomorrow so im guessing hes gonna send madmax's carb to the owner when he gets it.

I did manage 6 cycles tho! with no brakes!! so its 3/4 of the way broken in!

[Gator]

Thanks for your help Barry!    And Max!  I hope that the new carb does the trick.  I talked to Jason (owner) last night, and he told me to hold on to it and get it running better.  I also stopped at Paradise Hobby and bought a new gallon of Trinity MHP.  My Uncle will be here tomorrow for the weekend, so I probably wont have time to mess with it until he leaves.  I really hope the carb is the problem...

[SupaMan]

if the carbs not the problem then i dunno what it is.

[Gator]

Finally!     I fixed the problem!    

Was the piston installed in the correct direction (i.e. not rotated 180 degrees)

   No it wasn't!  I had a Traxxas Tech Support guy tell me to look into the exhaust port and turn the flywheel and if at any time I see the connecting rod, then the piston is in backwards. 

I took the motor out, turned the piston around, and sealed the carb/backplate!  It runs excellent now!  I'll finish breaking it in and ship it back to Tallahassee.

[Explosive Racing]

Awesome!!
Glad you found the problem.

[docphysics]

Yep, its always the little things that seem insignificant.   

[SupaMan]

that sucks i shoulda took it apart then i woulda looked like a hero