• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • ✓ Friendly & passionate RC enthusiasts
    • ✓ RC tips & troubleshooting
    • ✓ Buy, sell & trade RC gear
    • ✓ Share builds & upgrades

Throttle servo sticking

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
J

Jman30808

RCTalk Basher
Messages
76
Reaction score
0
Points
0
Location
Saginaw
RC Driving Style
  1. Bashing
  2. Racing
Ok so i fixed the last problem and went to play for a few. The aftershock is running good. I'm havin fun big ass wide open parking lot. After i got everything tuned and it started warming up. I flipped it... No prob just a few scratches. It stalled so i fired it back up, it started just fine... Then i touched the throttle, and off it went. WOT across the parking lot. Well i got it stopped (My leg still hurts but it better then hitting a solid object) and started looking it over. Antenna wire was frayed from sliding on its lid. So i fixed that. and went out today and after it got warm it started to do it again. I grabbed it before it took off. No traction on ice thank god. I checked the throttle return spring and its in good cond. Is there anyway to test servos??? I don't have anyothers here and i don't wanna buy one unless i have to. The servo thats on it now is a JR z270. If anyone could help me i'd be thankful.

Joe
 
Pull the servo arm off and check the splines on the servo shaft and where the arm fits on the shaft. I am thinking stripped splines in the servo arm where it fits on the shaft.

Had the exact thing happen to my Savage. Almost blew up my brand new LRP due to a silly stripped servo arm.
 
i pulled the servo apart last night and i didn't see any problems with it? the splines looked good on the horn, and all the gears inside looked good. There isn't any binding on the linkage. Its really weird. i'm starting to think i should have just bought a new one and not bought used.... but then i wouldn't be learning all of this so
 
Never run any car, electric or nitro, till you've checked all the movements of the servos without starting the car.
If the servo checked out then it's most likely binding at the carb.
If it took off at WOT running, then it will stick at WOT while you're checking it, and that's how you find the problem.
 
i did check it before i ran it, and it worked fine. thats what i can't figure out. i checked it all out both times that it happened. both times it worked fine until it started to get warm. thats when it starts acting up. i'm gonna pull the carb and go through that tonight when i get outta work. see what i can find...
By the way thanks for all the help. I know that i'm a noob and alot of people have helped me out so far. This truly is a great site.
 
How do you know you're not having a Tx/Rx problem. It might be losing it's signal at a certain range, rather than having a problem at a certain temp.
Put it up on a block with the wheels off the ground, let it warm up and start walking away from it while it's running. Twitch the trigger and move the steering as though you were driving it. Walk as far, or farther than it would be if you were driving it. See if it happens again.
 
Thanks for the tip Rolex as soon as it warms up outside i'm gonna give it a try. Its been below 20 outside for the last few days and i don't have a shop to work in thats heated. When it warms up and i get a chance to try it out i'll let you know what happens. I did tear down the carb... It was really dirty. Had a torn boot on it. Got a new one at the lhs. Gotta love it they have just about all the parts to fix anything on losi in stock.
 
The 590M or 650M would both be a better upgrade... I went a little overboard, but it's because I replaced the stock steel disks with a vertigo CF disk. It's not as grabby and doesn't start to bind over time like stock steel/steel or LST2 steel/fiber does. I'm running a hitec 985MG. (172oz metal gear)

I think my buddies just went to a 590M because they can be found on ebay for around $20.
 
Yea I tried what rolex said. Tried if first not running easy 1/4 mile range. Then tried it running, same thing. I could have walked longer but its just too damn cold out. I'm starting to think that the servo is just going bad. Gonna see if the lhs has one that they can try in it to see. If not i'm just gonna have them fix it cause i'm outta ideas.
 
OK well i got the problem fixed... I hate water. I pulled the cover off the servo again. And i found one little damn drop of water. It didn't look like its the first time that its happened. The joys of buying used. There was a little bit of corsion on the board that i missed seeing the first time i looked. So i went out and got a 590 and it works great now. Thanks again for all the help, and ideas
 

RC Builds

Back
Top