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Emaxx help needed

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SVORay

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I'm trying to figure out some issues I'm having with the Emaxx. The truck quits working everytime I go WOT with it but will cruise around just fine around a 1/4 - 1/2 trottle. Once it stops working, it will continue after a few seconds...as long as you don't WOT it again. Now when I set it up on the bench, I can run her and long as I want with zero issues at WOT. I also noticed her going in reverse once you cut the remote off first, but not sure how that relates to this. Now I've replaced the EVX but the old one did the same thing. The only difference seems to be the new one actualy starts working a lot quicker than the old one would once you WOT it and the truck stops working on you. I'm running some 7cell (8.4) 3300 packs as well and were fully charged. I also replaced all the connetions with Deans plugs along with one of the stock titans. I still run both stock titans as well.

Thanks for the help and info
Ray
 
I had the same issues with the one I just bought for my son. I'm not sure if you tried this, but I reset the ESC and it solved all the problems. I also found out that the antenna wire on the RX was way too short. I called Traxxas and they said the wire should be 24" long. I replaced the wire, reset the ESC and everything cleared up.

Hope this helps!
 
Monkey Wrench said:
I had the same issues with the one I just bought for my son. I'm not sure if you tried this, but I reset the ESC and it solved all the problems. I also found out that the antenna wire on the RX was way too short. I called Traxxas and they said the wire should be 24" long. I replaced the wire, reset the ESC and everything cleared up.

Hope this helps!

Hey thanks

I'm not sure how to reset the ESC...I pushed the button a few times and all it did was flash a red LCD a few times. The truck still acts the same way :ponder2: The antenna has always been short but never gave us any issues. Is there a chance the Receiver is shot and sending it screwed up signals?

Thanks
Ray
 
I'll bet dollars to doughnuts the antenna wire is too short.

To reset the ESC, all you need to do is:

1. Disconnect the motor leads.
2. Set the trims on your TX to zero.
3. Turn on the TX.
4. Turn on the ESC (power the truck up).
5. With the TX throttle at neutral, press and hold the ESC SET button until the LED turns solid red, and then release the button. You are now in programming mode.
6. Pull the TX throttle trigger to the full throttle position. Hold it there until the status LED turns solid green.
7. Push the TX throttle trigger to full reverse. Hold it there until the status LED blinks green.
8. Release the TX throttle trigger allowing it to return to neutral. The status LED will turn solid red, indicating that the throttle is at neutral and the programming has been completed.

You need to make sure the TX Throttle Neutral Switch is set to the 50/50 setting.

If you happen to have the manual, check pages 25 & 26.

Good luck! I'd suggest replacing your RX antenna lead if it is shorter than 24", though. Even after I programmed the ESC, when I replaced the lead, it was a night and day difference.
 
Well I tried all of that including replacing the receiver with a full antenna and it still does nothing. The weird thing is the truck will run WOT either forward or reverse on a stand all day long but stops after WOT on the ground:ponder2: I'm wondering if the spur is slipping or something else is giving way...It's not like there is much left on this truck that I haven't replaced. Also I wonder if these batteries are causing my greef since this started around the time I got them but can't imagine how they could:ponder2:


Thanks for the help MW
Ray
 
Only other things I can think of are either the spur is slipping, the pinion gears (or at least one) on the motors is slipping or the diff's need checked out. I'm assuming the tranny has been looked at, but since you do not indicate hearing any grinding, I cannot imagine the culprit being there.

If I think of anything else, I'll pass it along, but surely, someone else here has or has had an E-Maxx and probably knows the answer.
 
I had to reset the evx on my son's E maxx but like MW said all was good after that. If the motors are still running when the truck "quites" you have a drive line problem, follow MW's advise. If everything quites, I would say the evx is taking a dump, return to traxxas and they will repair it for $25.00 plus shipping. The short antenna wire will have an affect on your range but should still work within a very close range.

Good luck

Just had a thought...Make shore the tranny is not stuck between first and second gear.
 
This truck has become a huge mystery lol

I've replaced the EVX already and things got a little better...the truck actually moves now but dies on me like mentioned. Before I changed the EVX, the truck wouldn't move at all no matter what I did. I've double checked the spur and replaced the pinions also. "I'll double check those pinions just to make sure they're on good and tight."The gear box was gone through a while back when I heard some grinding noise from when I install a diff upside down. Everything turned out ok and the grinding noise stoped. I replaced one of the titan motors also since one of them had a broken fan. Just wanted a motor with a fan that worked to help it stay cool. Then I installed some heat sinks to futher help keep them cool. The only thing that I have not replaced or taken a part on this truck is the servos, which I'm replacing the steering servo in a few days anyways, and the front diff. Everything else on the truck has been either replaced or taken a part and inspected.

The next thing I've going to try is to double check the pinions and make some adapotrs so I can try some of my old 6cell packs out. I switched over to a Deans plug and so I can't just plug my old packs up to check them out. It seems to me all this started when I swaped in a set of 7cell packs.

Thanks for the help and advice guys
Ray
 
Well a I finnaly figured out my issues with my son's Emaxx...those 7cell packs. I'm not sure if it's the packs them selves or if the stock ESC just can't handle a 16.8v set up. I made some Dean/Tamyia adaptors and pluged in some old 6cell packs I got laying around here and the truck does just great with them. Anyhow, does anyone know what the stock ESC can handle volt wise or a way to check out these 7cell packs? I'm just trying to find out now if these packs are junk or if I'm running to much voltage through the ESC.


Thanks
Ray
 
Ray, all the documentation in my E-Maxx manual states that the stock 14.4 EVX can handle dual 7-cell packs, which puzzles me as to why you are having so many problems with yours (I have not run 7-cell packs on my son's yet, so I have no point of reference.)

I did find this, though: http://www.traxxas.com/support/index.php?action=artikel&cat=91&id=280&highlight=7 cell

I'm not sure if it will provide any assistance, but it may.
 
The evx can handle a pair of 7 cell packs with no problem, are at least my son's can. Sounds like your batteries crapped out.
 
Last edited:
Hey Maxxin, when you did the 7-cell mod., did you add a battery to an existing pack, buy a 7-cell pack or build your own? I'd like to do the 7-cell mod for my son's E-Maxx, but would like to hear how others went about it.

As for the EVX, both the manual and the documentation on the Traxxas site say the Novak EVX on the E-Maxx can handle the voltage, so long as you continue to use the stock Titan motors.
 
Monkey Wrench said:
What is this? I'm just asking for a bit of clarification on what you are referring to since I see nothing linked or posted, ace.


sorry about that monkey. i made a mistake. i was looking at more then one thing a once. but if this is the esc you guy are refering to it should be fine with 14 volts.

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXAJD6&P=Z
 
Well everything got much better once I switched back to the (14.4v) 6cell system. These 7cell (8.4v) batteries are brand new, is there away you can test the packs to see if they're good? Just wondering if the packs are back because I've heard of people having good luck doing this with the stock ESC. Anyhow, I'm going to look into a few sets of some side wired 6cell packs I found on ebay. Those top wire packs has issues with the battery tray...it's just to tight for those types for some reason. I really should have just bought a new Emaxx instead of buying a used one :( Oh well, you live, you learn ;)


Thanks for the help
Ray
 
Monkey Wrench said:
Hey Maxxin, when you did the 7-cell mod., did you add a battery to an existing pack, buy a 7-cell pack or build your own? I'd like to do the 7-cell mod for my son's E-Maxx, but would like to hear how others went about it.

As for the EVX, both the manual and the documentation on the Traxxas site say the Novak EVX on the E-Maxx can handle the voltage, so long as you continue to use the stock Titan motors.

I added a cell to a 6 cell pack. Just mount it at the 10 o'clock position of the pack so it won't interfere with the battery strap. It seems like I saw some battery straps that are made to go around the standard top mounted
7 cell but not sure. I have been running the Titans since I bought it. There is a guy that mods the the evx so it can handle hotter motors, I'm thinking about giving it a try.

SVORay I have some batteries you might be interested in. Check you pm's.
 
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