throttle Works intermittently

[kmak]

Hello, I was trying to battle this issue on my own, but I can’t so I am seeking help. I just got done working in the engine to my Rampage XB, I had a nasty crash and things start going south since then.


I fixed it up got it all running again and everything seems kinda fine. However at the end of my first drive since I fixed it up, I realized the motor is not responding to the throttle as it should. The steering is fine no prob, but the throttle is not very responsive.


At first I thought the battery was going but charged and changed everything but the result remain same. When I take off the cover and press the throttle trigger, it doesn’t pull back the throttle cable to rev the engine, I have to pull it like five times to get the engine to respond.


I need to get this truck back up, I have a 1/8 DHK Maximus electric and Traxxas X0-1 electric. But none of them gives the vibe of the Rampage, it’s my first gas and I am hooked. Please help.

 

[Guest]

You might need to set your throttle trim. Also move the throttle servo manually to make sure the linkage is not binding.

 

[Deluge]

Could be a stripped servo horn. Just a thought.

 

[rampage idiot]

Stripped servo horn or the screw might be loose on the horn

 

[andyken]

collar/set screw on linkage?

 

[kmak]

Thanks for the responses from everyone. I am relatively new to this; however would it be a stripped servo if when it does work it works fluently? So in other words, if I pull the trigger 5 times it may not respond, but for the next 10 or 15 pulls it will work fluently. When I look on the throttle cable it works for those 10 to 15 pulls. Then for another 5 trigger pulls it doesn’t respond and the throttle cable doesn’t move or budge at all.

 

[Deluge]

Is this a new servo, or the stock servo?

 

[Michaels12]

My shot in the dark...the solder connection on the board in the servo, but it could be on the plug end. Intermittent open circuit.

Get a hitec. About 25$ on eBay

Good luck

 

[Chief409]

I'm using metal gear servo's only. And it could be the plug at the receiver. Get some contact cleaner (CRC is good, available at Home Depot, make sure it's plastic safe), clean all the plugs. If it isn't any of that, get a new receiver and servo, I've had servo's cause intermittent receiver fails after a bad hit. Tried just changing the servo, but the problem came back. I think the momentary over current damaged that RX channel.

 

[kmak]

ok thank you. I read somewhere and it said the crash that I had, could have damaged the crystals. Does this make sense to any of you all.

@ Deluge: its a stock servo.

Ok I have never changed a server or/and receiver before, any suggestions please that could assist me in the change? Also do I need to change the transmitter as well?

 

[Ildy666]

Isnt it 2.4 not crystals?

 

[Guest]

its a stock servo.

Enough said. Replace it.

 

[Deluge]

Ok I have never changed a server or/and receiver before, any suggestions please that could assist me in the change? Also do I need to change the transmitter as well?

Changing the throttle servo is super easy. Open up the radio box and disconnect it from the receiver. Remove the servo horn. Remove the four screws that hold the servo in place and it's out. Just reverse the steps to put the new servo in. Before you put the servo horn on, power on the system and center the throttle channel, then put the servo horn on as straight as possible. It won't be perfectly straight, but you can tweak that with the throttle trim.

To replace the receiver, open up the radio box, unplug everything that is connected to it. Put the new receiver in and hook everything back up. The steering servo connects to channel 1, and the throttle servo connects to channel 2.

You can just buy a replacement receiver and bind it to your transmitter.

 

[Guest]

If you are running the factory transmitter, it is a rebadged Flysky. So the $10 3ch receiver works.

 

[kmak]

I change the receiver and the servo still works sometimes. So I guess it’s definitely the servo. What do you mean by stripped servo horn?

 

[Guest]

The teeth inside the horn can wear out causing the servo spline to just spin or slip inside the horn.

 

[kmak]

Ok, however would that happen so quickly? Further more it worked very well prior to the crash; I didn’t have any form of issues with it. But as soon as it crashed and I reassembled it, I realized that the steering only works sometimes. I am a bit confused.

 

[Guest]

If the servo is at a stand still, and all of a sudden the linkage get pushed against it, something has to give. Stripped horn, stripped internal gearing or maybe just a broke connection inside the servo. The factory servos can be very short lived without a crash. To avoid future issues, I replace mine on every fifth scale right out of the box. Just preventative maintenance when I first set them up.

 

[kmak]

Okay when you change your servo, do you change for both throttle and steering as well? which servo do you recommend I get? I would like to buy it today

 

[Guest]

I do.

The throttle is what normally goes out first.

I use Hitecs

The 5685 for throttle/brake

The 5765 for steering

A lot of guys use the 5645 for the throttle/brake.

Since I run lipo receiver packs, I find the 5685 to be faster, smoother and more quiet.