just installed BL-WOW-now problem
 

just installed the BL power for the first time in my 3906. MMM + 8XL. :D everything was fine through 2 sets of batteries. 7 cells then 6. huge diffrence in the 7 cells, HUGE. so i waited a few hours, played some GTA 4 and charged the 7 cells up, swapped the tires for dirt from street and took it down the road at the construction site.
20 min into my play time truck just stops. jerking but no movement. forward and reverse act the same. here is a small video, from my cell, sorry for the quality. but PLEASE help me out here.
i installed the idler gears from UE so i know thats not a problem.
as you can see, i can turn the spur gear 360 degree's but then stops. this is annoying and i am not sure if this is a problem or not.
there is no radio interferance. batteries are all full, even radio. so there is a problem somewhere else.
when i take it off the ground everything is fine. on the ground, nothing...

please please please help here.. 2 videos...

http://i108.photobucket.com/albums/n...0/th_jumpy.jpg

http://i108.photobucket.com/albums/n...50/th_spur.jpg

Have you pulled the tranny apart yet? It's been years since i've owned an e-maxx but i remember there was a small pin on the main spur gear shaft that would always break.

Mike, thanks for the motor and stuff. niiice...

i did pull everything apart but i dont know what pin your talking about.

also, i just disconencted the driveshafts and the problem went away... ?? DickyT was over today and we heard the front one starting to go. of course, it was wheelie from one end of the street to the other, on the ground we heard nothing, once the front wheels touched, we heard it chreechsnappcracklepop (not sure how to spell the noise. lol )

Was that first video full throttle? Sounds almost like a little clicking of something catching, then not catching. Could also be an unfortunate MMM failure though. Do you have another ESC/motor setup to test and make sure it's not either component (do all possible combinations if you can).

nope. blown titans. :\ yes full throttle... MMM problem huh? @*(&^(*#^(*#&)*#& NOOOOOOOOOOOOOOOOOO

I don't have my MMM yet but that does not sound like an esc failure, it sounds like something is grinding. Maybe the diffs? Have you disconected your motor and try rolling the truck yet?

ya with everything one just like i was ready to go, there is no problem. too the driveshafts off and pulled the trigger and there was no problem.. you think this could be a diff problem? i dont know how to take them apart or even what to look for. i am new but picking up ya know?

Time to hit up the exploded views:

http://www.traxxas.com/products/elec...maxx_views.htm

The input shaft of the tranny has 2 little gears on it, both held in place by a small pin that goes through the gear and shaft. That may have sheared and gotten lodged in the gears. If however the problem only exists when the diffs are hooked up to the tranny with drive shafts, its more likely the problem is in one of them. Not suprising really if they are stock traxxas diffs.

well i know the front is going so i might as well get a set. what is your honest opinion, keep price in mind, i am not rich by far. but what is the best bang for the buck on this stuff.. and where?? UE is expensive but i dont want to go buy stock parts and break them in a week ya know..

Yeah, I'm starting to think it's not an ESC failure. I figured since he said it ran fine in the air, but when on the ground it did that, that tends to be a sign of a blown or screwed up phase from my experience.:gasp:

It does sound like something is up with a diff though; more probable I would guess.

In order of cheap to expensive:

1. 3905 diffs
2. Alloy cup and ring gear with 3mm screws
3. Muggy/LST diffs: http://www.rc-monster.com/forum/show...709#post171709
4. FLM hybrids or UE

Before you go and start buying expensive parts that you may not need i would really look at the those exploded views on the traxxas website and find some time to take apart the tranny and diffs and see what is going on.

i did take apart the tranny, noticed small plasic shavings, not everywhere. but there was evidence for sure. i cleaned out and put back together.

but remember, i have disconnected the driveshafts at the tranny and everything is fine. when there is no resestance when they are connected, up in the air, there is no problem either. so i think i am going to take the front and connect it, see if it jerks like that. then try the back. i know my front is going, maybe this is the problem.. will update in 5 min. scratch that, 1 min.

thanks for all these ideas guys.. seriously....
brb

same problem when either which one is connected alone.. guess i have to take the diff apart and see whats going on in there.

If there is one thing that i have learned on this forum all these years is that grinding and clicking usually means blown diffs.

shouldnt take me too long to take em out right?

i am looking up the manual right now..

I just blew 1/8th scale gears out with an outrunner, it had the same symptoms, i managed to strip both pinion and spur

cost on these? ball bark? links?

Just went thru one version of this - 3905 diffs - ebay, one was $19 other $21 shipped, so the pr was $40. I'm going to run them without taking them apart, but prob a mistake - they feel like they need shimming. Haven't installed front yet, may break down and look inside and check it out.

I have done the other route using flm diff cups with their modded ring gear and new pinion - those are $30 each. Strong enough for a 28 nitro, but how well stand BL power, don't know.

Muggy diffs - no idea.

UE - 6 sypder diffs used runs $150 and up, may find cheaper, ebay or UE BST easiest places to locate. They are in stock at UE, new at $260. The 8 sypders start used around $175 and new they are $299 (new, in stock).

The flm hybrids - cases are $140 and you'll need a pr of diffs and pinions at $60 - 65 each so parts will total $260 or so.

Which is best, thunk the UE 8 spyders is the absolute best/strongest, they still need bulks however which the hybrids don't You could buy the ofna 8 spyder diff and pinions and put them in the hybrids. The cups hold up better than stock, not much else can say about them.

im liking the 3905 for 40 bucks. for right now, that should do it for me until i decide to go balls out. not for a while, but we will see. heh.

you think these 3905 diffs are stronger than the 3906?? my guess is yes, but i dont know much yet..

???

http://cgi.ebay.com/2-Aluminum-Diffe...QQcmdZViewItem

Mike has some aftermarket diffs in the site store for $125 each you could give them a look...I have them on my backburner if I blow my diffs I will probubly get a pair

http://www.rc-monster.com/proddetail...flmrvdf&cat=44

thats about 100 more than i want to pay. each. HEH.... for now, i think i may just get some 3905 ones or some aluminum cases and stock 3905 diff ones from ebay for the same cost.

The 3905 diffs have held up to my brushless E-maxx, been beating it for a couple months now.

FWIW the Hybrids can be done for less than $260, I'm in the process of upgrading my truck with FLM Hybrids, Hyper 8.5 diffs, and the goodies from RC monster to use my stock 3905 drive shafts and the total cost was $225, still pricy but I'm getting some nice upgrades!

my vote is for a blown motor phase, just like Five-oh-joe said...
you are seriously risking frying the esc if you continue forcing it to spin a damaged motor... check your motor screws... if you used the screws supplied with the feigao, then odds are that the internal motor windings got shorted...

well the motor has less that an hour on it, brand new from Mike. if it was a Lemon, we need to deal with it. otherwise i need to find another problem. but i didnt get a chance to take the diffs apart.

i do have to say this though guys... when i punched the throttle, the motor was clicking like that, jumping or whatever you want to call it. the video wasnt 1/32 on throttle, it was full throttle. i would think that the motor would be spinning and i would just demolish any diffs or anything else wherever the problem is.
am i wrong by thinking this? could it really be a bad motor? even if it is brand new? the temps were low, not like i killed it or anything. i was EXTREMLY careful with the temps being new to BL and all. i barley got on the throttle.

could also be a broken or loose or bad solder joint between the esc and the motor...

at any rate, one phase doesn`t work... either because it gets no voltage feed from the esc, or because it`s broken somewhere in the winding...

So I'm NOT as crazy as I thought I was for thinking a possible blown phase...:lol:

i dont think anyone here is crazy. all you guys are very intelegent, thats why I am asking YOU the questions ha.

i am very worried about my problem guys. i am going to go home tonight and riop everything apart, take some pics and post them up.

well, i took the diffs apart and saw nothing significant. i am soaking everything in acetone right now and will attempt to put back together tonight. need to clean all the crap off and re-grease them. i will take some pics once i have cleaned everything for your viewing pleasure.

one thing i never tried on my narrowing down the problem process though. hooking everything up except the wheels and seeing what happens.

the motor turns freely when not connected to the pinion.
pinion to spur to tranny spins fine.
driveshafts to diffs is where the problem was. but i never checked it without the tires on to see if it spun freely without the binding. that is my mission tonight..


almost forgot, i got these today for 100 bucks shipped.


http://i5.ebayimg.com/08/i/000/f0/40/0c31_1.JPG

http://i15.ebayimg.com/06/i/000/f0/40/0ccd_1.JPG

ok guys, here are the pics of the diffs.... i see no major problems... what you think? they all look the same but no teeth are missing or anything. maybe just really worn.. not sure, you be the judges... oh and this isnt my camera so i have no idea whats up with the multiple pics. sorry guys. i almost feel like an idiot posting these, but whatever.

http://i108.photobucket.com/albums/n...0/DSC03383.jpg

http://i108.photobucket.com/albums/n...0/DSC03384.jpg

http://i108.photobucket.com/albums/n...0/DSC03385.jpg

http://i108.photobucket.com/albums/n...0/DSC03386.jpg

the multi pic looks pretty artsy...you should frame and submit it to an art gallery......:-)

Maybe some gears look a tad sharp, but I think that's just the angle. I think it could very well be a possibility that your phase (in the ESC, not necessarily the motor, though the motor phase going kaput is a possibility) is blown or something is not right with the ESC if the diffs are all well and good. Did you install those purdy diff housings yet? Maybe there was a little slop in the stock gear case, and the aluminum bits will help align things nicely (and thus prevent any clicking).

I'm more inclined to believe it's the ESC, just from the videos. Especially as you say, it runs fine if you pick up the truck (very little load), but stutters like mad and does that odd twitchy crawl on the ground (not a ton of load, but an appreciable amount compared to freewheeling in the air).

I dunno dude! I say trouble shoot the electronics next if you or anyone else can't see any issues with the gears.

Nice, Comobs? or are they Hybrids?

well, i put everything back together last night but didnt get a chance to install in truck. i saw no point since those bulks will be here tommorow. i will pop the new ones in, see if its the same problem. if not, i know it is the esc or the motor. then i have a whole new bag of issues to deal with. :diablo:

If things work fine in the air and only have issues when "loaded" on the ground, I too would suspect something mechanical (diffs/tranny/etc).

Although, it could also be a bad motor/power connection solder joint. When in the air, not much current is need so everything works fine. But on the ground, the increased power needed to move the vehicle increases the current. If the connector joints are crappy, you could get a cogging-like action.

The video is a little fuzzy, but the clicks do sound mechanical, not the motor, so I'd look at the diffs and tranny first.

Brian, thank you.

i have those combo bulks coming in hopefully tomorrow and will start from there. no sense in me installing the diffs i have now and putting back together just to see if it works, which will probably not. if the problem persists, i will take the tranny apart and see whats going on inside there. when it was apart the other night, i did see minor signs of wear after installing the steel idlers but very minimal. only in the corners.

as for the solder connections, DickyT did solder these for me and claims there shouldn't be a problem there. unfortunately when my MMM came in, there were no Bullets. while writing this response, i just got an email stating they are in the mail. so i will defiantly add those when they come in.

to everyone: sorry for the Acid Flashback looking pics, not my camera and i didn't want to start changing settings. my finance took mine to NY for the week. tomorrow (hopefully) i will post up pics of everything from my camera and take a new video if the problem is still there after i install the new combo bulks...

thanks to all for your help!

In the meantime, take your tranny apart. The pin people are talking about is the one that holds the gears to the top shaft. It's pretty obvious when you have it apart. Even if it looks good, you might as well bullet-proof now it by using a cut-off hex wrench to prevent it from becoming a problem.

After all;

An ounce of prevention is worth a pound of cure.

and

The system is only as strong as the weakest link.

and any more cliches that apply... :smile:

a cut of hex wrench huh. i am assuming once i see what this pin is, i can match it up to get the size and go from there. but there is more to bulletproofing the tranny than this..

all i have done to the tranny is added the steel idler gears. i dont want 1st but i dont know how to convert it to 2nd gear only. i have looked for a write up and found nothing.

one more thing, what else should i do, within price reasoning, to bulletprooof the tranny?

Yeah, whatever size that will replace the pin. You might want to grid the corners of the hex edges first so it fits very snug.

Converting to second gear can be as simple as screwing the dog carrier (the part the shift fork sits in) to the gear of choice. Or, you can look for the gmaxx coupler (Found on the gmaxx website for $15).

That's about it to bullet-proof it really. I suppose you could go all out and get all steel gears, but that's unnecessary.