E-MAXX issues.... need help.

[Desert_Irish]

I just bought an older E-MAXX and I am having some problems that I need help with. I picked up a couple of Venom 3600 NiMh packs, charged them up and ran the truck for the first time. Problems I have noticed:

1) Serious lack in power. I charged the packs @ 4amp for over an hour, letting them go into trickle charge. I re-did the ESC setup for neutral settings, and when I hammer the throttle, it goes but not with the authority that you would exspect. I can't even power up and over a curb. Transmission or clutch issue? I made sure both motors were turning, and I can hold the truck stationary and pull the throttle on dirt with hardly any wheel spin.

2) While running it, it would stop by itself at times and the ESC would start do things on its own.... go in reverse or forward uncommanded. I checked all the connections with no fault found.


I am new to RC again after many, many years, and all this stuff is new to me.... the help would be greatly appreciated.

[Kalthor]

Obvious question. Is it used and if so how old is it exactly, was it pretty dirty when you got it?(shows lack of previous owners care to the vehicle). Since you redid the esc throttle settings I couldn't imagine it being that. you could try a different pair of packs. Venoms are ok, but the E-maxx new or old tends to want a little more power then the venoms can sometimes deliver but your absolute LACK of any power is a little suspicious. Run both motors unbolted to the motor plate. Even though they both turn over one motor could be worn out. If its that its best to replace both motors. Same principal as rebuilding shocks. Worst case the esc has a bad FET or circuit. I have even seen problems similar to that arise because somethings wrong with the transmitter or receiver, even the crystals. I own an E-maxx myself and work at my LHS so I'll give any advice I can offer.

[Wakesurfer]

Hopefully it's not the ESC. Venoms aren't great, but unless yours are really hurt they wouldn't make the truck that much of a pooch. I'd check the motors with the pinions off the spur. While they are loose, make sure there is no binding in the drivetrain. It should spin free without the motors dragging on it. The brushes may be gone on the Titans. They do wear out, but replacements are very expensive. The glitching may be related to the lack of power, but if it's not it would be a good idea to find the cause of that too.

[Desert_Irish]

Ok, if the motors are toast, what would be a good brushless setup? If I am going to replace motors, might as well get the good stuff.

[Kalthor]

There are a couple ways you can go with brushless. You can use a Novak system. They just re-released them as a the 4.5/6.5 Pro. The ESC is improved and they now have 5mm shafts and will soon offer 5.5 and 7.5 turn motors too. You could also find an older one and use it too. If you do don't worry about anyone saying the shaft is too short. You don't need the pinion to be 100% over the shaft although it would help. You can go with a Mamba Max and Feigao L/XL motor combo. You will need a BEC though so you can run over 3s LiPo or 12cell NiMh. a good Feigao is either 10-8l or 9-7xl. you can buy them from a few places I got mine from impaktrc.com. You also could wait for castle to bring out the Mamba Monster in ESC/Motor combo which will run roughly $400 or just buy the esc(when they get more in stock) and get either a Feigao(Nemesis blue or Wanderer are about the same) motor, or go real fancy and buy the ESC and a Neu motor. O so nice the Neus are, but the motors cost like $250. Honestly the Mamba max/Feigao is one of your cheapest options. The Novak is amazingly user friendly and easy to install costs about 280$. The Mamba Monster will be more expensive, but will probably give you the biggest amount of performance and cost around $450 for motor and esc. Both Castle and Novak have awsome warranty and customer service so you can't go wrong with either one. Those are my suggestions. I also suggest looking around a lot before deciding on what combo you throw down in that thing.

[Wakesurfer]

The Novak shaft lengths shouldn't be an issue on 3906 Maxx. The 3905 has a different slipper that puts the spur farther away from the motor plate. Getting the rest of the drivetrain to survive a high torque brushless system will be more of an issue. The 3905 Maxx has a tougher transmission, and the drive shafts and diffs are the Revo 3.3 spec stuff. The 7xl/MMM combo makes for big power. An 8 or 9xl would probably be a better choice unless you just want huge speed. Temps should be easier to control, and the 8 or 9 won't be quite as hard on the other parts. All the parts are out there to make the 3906 a killer truck. If you ESC is ok, I'd say replace the Titans and run it until your ready to go all out. Then do the MMM with a Neu hang on.