Engine Goes Wild....

[cenbuggywiu]

Hi there,

Well here's the deal: I've got a CEN ATX buggy with the .16 motor, 4wd. I've run almost a quart of fuel through it and I've run into a little problem. Basically, I'll start it up, drive around a little bit a low throttle (10-15ft away) and then it just takes off all by itself. I have absolutely no control it just opens up all the way and rips it up. Now, as cool as this looks....it's not cool at all. I just prayed it would flip because I have no way to stop it. Any suggestions? I've already put in new batteries, a new glow plug, and checked that the servo responds to my inputs. Additionally, this thing goes through fuel like nobody's business... This is really nerve racking and has already led to $50 in damages..... :-( Any help would be great!



Joe

 

[kwong2001]

Failsafe...also, the car may be getting out of the range of the radio.

 

[cenbuggywiu]

I'm only like 15ft from the car (tops) when this happens, I've already ordered a failsafe... what may be causing this?

 

[kwong2001]

Does your steering go out also? Cuz if you still have control then it's not the range. Could be the linkage for the throttle. Also, your gears might be stripped in the servo, which could cause your problems

 

[TRDStreetFighter]

interference... car alarms, radio... depending on what type of radio system you have... fail safe is a good investment... plus you can have a bad transmitter or receiver...

 

[robriguez]

could be the crystals, if you have a spare set swap them out and see if it still happens. If so then try the receiver.

This was happeneing to a freind of mine and it drove us nuts trying to figure it out. Turned out to be his receiver.

 

[cenbuggywiu]

Thing is, it's brand spankin' new and I don't have another receiver.... :-(. I wish I had a LHS to go to!

 

[gutterboy]

I got this problem with my .15 T MAXX. I was only standing about 6 to 8 feet when mine takes off. I have tried new batteries, reciever, crystals, radio and nothing. I checked out my battery box on the truck and took it apart and found that one of the wires was kind of crimped and it was kinda corrided. I dont no if that is the promplem because I have been working 16 hour days. But when I have a day off I am going to change the wire and clean it up, hopefully that will solve the problem. Check the battery box, it might be it.

 

[cenbuggywiu]

I just found out something of interest. I had one of my buddies working the antenna up the tiny little antenna tube and I left the room and went out to my car. Turns out he "trimmed" the bit of antenna that hung out of the tube off. I'm assuming this could play a part in my problems? If so how do I get the right antenna length for my receiver? I can just solder a piece of matching wire on but I'll need the correct length... AHGHHHHH:microwave

 

[gutterboy]

Yep, that is probably the problem, but something I dont understand is that I have seen some antenna wires shorter than others, but they do say not to cut the antenna wire. I have 2 T Maxxs and the one on my old T Maxx .15 is longer than the one on my O.S. It has the same reciever but different servos, dont know if that has anything to do with it. Well I hope that solved your problem and happy bashing.

 

[cenbuggywiu]

Well I now realize what the problem may be, but how the heck do I fix it !?!

 

[gutterboy]

Only thing I know is if you can buy a new antenna wire or make your own. If you have a LHS in your area you can call them and see if they have em. Good Luck

 

[Mugen-Racer]

I had the same problem with mine. Had a pinched antenna wire and eventually rubbed and had bare wire showing. Caused all kinds of grief. Ended up take Cat 5 cable and using one of the wires inside of it. Course I still had the other antenna, so I just made it the exact length. You can go to the LHS where you got it and ask if they know or if they have another, see if they can take it out and measure the antenna wire.

 

[cenbuggywiu]

the inner cat5 wire ended up being the right size? If so I've got reels of that layin' around here. I think I'll call Toyhaus tomorrow and see if they can help me out. I bought this puppy on e-bay and have no LHS around here. I'm down at college, thus away from home....and the hobby shop there.... thanks guys everyone's been a great help

 

[robriguez]

If your good with the soldering iron just open up the receiver and solder on a new wire. Only do this if you are GOOD with a soldering iron...Alot of people think they can solder. If you dont "know" that you can....take it to someone who does know or to your LHS. This way if they screw it up they can fix it for you.

Find out the manufacturer of your receiver and try to get some info on the length and guage of wire required. Just as too short a wire can cause problems so can too long. Just because the outer jacket of the wire is the same diameter of your antennae wire doesn't mean its the same guage. If you have a ton of CAT5 laying around I assume you nkow what guage is. Also make sure it is stranded core wire. You dont want to use solid core..its just not flexible enough.

Heres a good article on how to replace it yourself.
http://www.rccentral.com/qanda.asp?ATCL_ID=49

 

[cenbuggywiu]

I read that article, now a question are all antennas supposed to be 19.5" or was that just in his experience? And how does 2 inches less make such a big difference?

 

[gutterboy]

I would like to know that to, cause like I said in my post reply earlier my .15 T Maxx antenna wire is at least 3 inches longer then my other antenna wire. I just measured my .15 to my buddys 2.5 antenna wire and they are the same length.

 

[robriguez]

For the sake of this thread I just measured all 4 of my antenna wires. (2) JR rs3000 75MhzFM=18", (1) HPI 27MhzAM=16.5", (1) JR 27MhzAM=15.25", and (1) Ofna? 27MhzAM=17". All were measured from the outside of the receiver to the tip of the wire, give or take 1/8th inch, and I have never cut or trimmed any of my wires.

All I know is that I've been told that the length of the wire has something to do with the tunning of the AM or FM frequency. But from these results I can't see how......:shrug:

 

[chewyboy]

check out the connection on the carb. I had an engine do this once and it was the connection between the linkage and the carb. the connection there was very loose and once you got it up it would not slow down even though it sucked after i figured out what was going on it was pretty cool good luck with it.

 

[cenbuggywiu]

Originally posted by kwong2001
Does your steering go out also? Cuz if you still have control then it's not the range. Could be the linkage for the throttle. Also, your gears might be stripped in the servo, which could cause your problems

I'm still trying to figure this thing out.... my steering works fine, at least here sitting on my table. But when it goes crazy I can't tell if the steering is working or not, I know I can't turn the brakes on.... hmmm