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Servos spazming out...?!?!

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M

MAXXSLINGER

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ok....so my servos...ALL OF EM...seem to be twitching like a @(#$)*& as soon as i try to crank the car up.... all of them are sealed with plastidip...and have not had any water in em....and if they have...it was a long time ago...and they have worked fine since then...

i was gonna get a new rec for the truck...but i dont wanna do that till I'm sure thats the problem...

i use a futaba 3pm-fm transmitter


also...at full WOT...the engine just cuts right off...this just started today....could this have to do with the servo issues?? thanks for your help people
 
dbl check your batteries ,,,i had a similair rpoblem with my evader this past summer and all servos went wacky and i recharge the batts and it was fine
take care
rick
 
I've heard that metal on metal contact can cause interferance like that. Do you have a rollcage?
 
I had a similar thing happen to my pcr pro when I used a novak xxl rex. It turned out to be the RX. BUT as Herbieace said metal to metal rubbing can cause havoc to your electronics. Check for any thing of that nature. for springs on your throttle linkages you can replace them with fuel rubing or you can heat shrink the linkage with some thin heat shrink and get a large spring if needed. Don't think you will. Look for loose screws as well.
 
The wild twitching can also be caused by the Radio antenna being too close to the Rx.
If you have the radio in your hand while starting the truck, and the antenna is laying across it, that can cause it. Try moving it just a few feet, or keeping the radio antenna straight up, and see if it stops.
Does it do the twitching when the car is not running, or just when it's running, and it's close to you?
Since you asked about the engine cutting out, obviously you can drive it.
How does it respond at a distance?
 
jmarzilli said:
try replacing the crystal, my friend had a similar problem and that solved it
Click to expand...

I second that. I had a huge glitching problem a while back. The crystals did the trick for me. Also before changing em out, be sure ur existing ones are in tight and not loose.
 
the glitching problem happens sometimes and then sometimes it doesn't happen at all...

the reverse servo is all messed up now though somehow....going into reverse usually works...but then it wont go back into forward...until i turn of the engine or sometimes it will by itself....i dont understand...

what worries me more than the electronic problems is the cutting out at high speed...

seems like an engine prob...it idles high for a few seconds then goes lower..and off....
what are the factory settings for the lsn hsn and idle screw??

i know thats alot of questions, but i am trying to get this truck to be reliable and MORE enjoyable... :)
 
How the engine runs is the second problem.
You need to correct the first and most important one first.
I asked earlier if the twitching happens when the engine is off, or only when it's running. We need to isolate the problem one step at a time.

You DON'T want to be driving the car with a radio problem.
 
this happens when the engine is off or on...

the rev. servo will twitch so bad sometimes it will pop out of forward...
(all of em are twitching)


but then sometimes...theres no servo glitches at all during a run.....

i ran at least 4 tanks today...one of em went all the way through with no stalls and it had great power and whatnot... the other tanks had differnt problems each time...

btw...i must say...this forum and YOU (ROLEX) are such a wonderful resource....you guys are so helpful!!!I'm online pretty much all the time...so ill be on here quite often...i work with computers and i am on the net all day...then i come home and spend more time at the computer.,... :roll:
 
Thanks for the kind words, MAXXSLINGER. We're all here to help each other out. I started on this forum because I needed advise with a new engine, and found it to be a huge library of information as well as filled with humor and good guys. Never had a need to go anywhere else.
Okay, back to the glitching. If it does it whether the engine is running or not, that eliminates any metal to metal vibration.
The next thing to do is switch out the crystals, if you have another set. If you don't, to check that without spending money, switch crystals with someone else with the same radio setup. That means, if you have 27MHz, you need to stay with 27, but can go with a different channel number if that's all you can get. Same thing if you're on 75, you need to stay with 75. Also, if you're on AM, stay with AM.
By the way, before you start checking these things, you must be sure your batteries are new.
 
well...i have a futaba 3PM-FM 75

i was thinking...is it possible that the rec. antenna wire might have a cut or be damaged..causing glitching...

also, my onboard temp guage is mounted on top of the rec. box on the chassis....could that cause problems??


oh yeah...there is nobody around to trade crystals with... :( how much would a set cost roughly??

sorry again for all the questions.. :hammer:
 
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If you are able to drive the car around for a normal distance, it's very unlikely that the antenna has been damaged. A sure sign of a break in the antenna is limited distance, followed by a complete run-away. Also, a broken antenna wire wouldn't make the servos twitch when you are nearby.
You might want to invest in new crystals next. They are only about 10 - 15 bucks at a LHS. Always good to have a spare set. Let the LHS know it's for FM 75, then get something different than you have now.
If you now have red, get blue or yellow. Why? It's good to have another frequency to switch to when you bash with someone on the same channel. If it turns out that the old crystals are still good, at least you can switch out your crystals and run together.
It seems very unlikely that the temp sensor on the receiver box would cause a problem.
 
ok, ill go pick up a crystal set after work...hopefully that might take care of some of the problems...

thanks again for the help
 
no crystals at the LHS...damn...

anyways...i came home and tried rerouting the wires, and it seems to have helped possibly a little bit...

the servos reallly go crazy when i am cranking it up...but dont really mess up when its running...

I DID notice that my transmitter batts were at like 9 volts...and thats the lowest they have ever been....i went sorta far..and the failsafe kicked in...but at the same time..i think the servos spasmed again..when i got out of range....because it kicked into reverse..and then out of reverse...and then finally caught signal again, and made its way back to me...

i can't think of anything it could be besides the rec....the crystal....or low batteries on the transmitter...

I'm about to find out if the batts were the problem...
the battery in the car itself was fully charged though...
 
The batteries were mentioned a few times in this thread. That's always the first thing you do when there are radio problems. Put in brand new batteries.
It's not always the problem, but when you're trying to troubleshoot a radio problem, you start by eliminating the most obvious things first.
 
i figured since the trasmitter didnt give me the warning telling me they were low...i was good to go. Then i noticed that the readout on the transmitter said 9.2v, and i didnt know that was considered low... sorry for all the questions...but i think it did have to do with low batteries...now i just have to get it tuned right again...

hope i didnt waste too much of anyones time
 
yeah...I'm pretty stoked...

on to the damage today though... :(

i blew my rear diff....
just blew my front diff like a week ago..at least i have experience fixing it eh...

also;...i came into som $$$$$$$$$ and I'm thinking of what to do with it...

should i go out and get a mayhem RTR from my lhs...or drop more money into my maxx..such as a bigger engine and beefier tranny parts..

i sorta want a buggy, but i want to primarily bash....
would a mayhem be almost as durable if not moreso than my t-maxx?? or should i go buy a savage, LST, or REVO...???
 
"What should I get" is probably the most asked question on this site. It all comes down to what do you enjoy, or what do you want to try next?
The best advise I can give you is do a search, right here on RCNT, and you'll get endless honest opinions of every MT or buggy anyone has ever owned. Good points and bad. Prices and upgrades that are available. Reliability and weaknesses.
 

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