Goes without throttle....

[nimblecook]

Did my proper break-in now it just wants to take off when started. You fire it up, it idles a little high and the wheels start going mad fast. Throttle trim is all the way down, and servo is centered. The throttle on the carb sticks a little as well, not coming all the way back to 0 when you let go. Any ideas on what to do?

 

[designed2survive]

Looks like a couple of things

1- make sure your gas tank is properly vented (unscrew/remove the tank cap) If that fixes it, you have venting issues.

2- if the above doesn't fix it, it may be too lean on the low speed needle (L). Start the engine and turn it counter clockwise until desired RPM.

2- if that doesn't work, unhook the throttle servo arm, start the engine and see if it still speeds up. If it doesn't, you will need to properly set up the throttle linkage.

3- your idle screw may be need to be turned counterclockwise.

Worse case scenario, you may have a leak, but we will get to that if the above doesn't work.

 

[nimblecook]

Looks like a couple of things

1- make sure your gas tank is properly vented (unscrew/remove the tank cap) If that fixes it, you have venting issues.

2- if the above doesn't fix it, it may be too lean on the low speed needle (L). Start the engine and turn it counter clockwise until desired RPM.

2- if that doesn't work, unhook the throttle servo arm, start the engine and see if it still speeds up. If it doesn't, you will need to properly set up the throttle linkage.

3- your idle screw may be need to be turned counterclockwise.

Worse case scenario, you may have a leak, but we will get to that if the above doesn't work.

Awesome, thanks. Newbie to 1/5 scale and it's giving me a few issues, but that's how you learn. Played with the high and low settings to no avail, and then noticed my throttle on the carb isn't coming all the way down to idle unless I do it manually, then idles and sounds great. So I've been trying to set without an absolute zero to start, no beuno. Going to try your throttle linkage trick in the morning. I'll let you know how it goes.

 

[designed2survive]

Awesome, thanks. Newbie to 1/5 scale and it's giving me a few issues, but that's how you learn. Played with the high and low settings to no avail, and then noticed my throttle on the carb isn't coming all the way down to idle unless I do it manually, then idles and sounds great. So I've been trying to set without an absolute zero to start, no beuno. Going to try your throttle linkage trick in the morning. I'll let you know how it goes.

@nimblecook Check your throttle trim on your radio. It's possible you may have accidentally bump it up forward a little bit. You can also use that trim to help you set the servo properly if needed.

 

[Mikev7]

Don't overtighten your gas cap.

 

[rawb4291]

Don't overtighten your gas cap.

My MT was doing the same the other day. It ended up hitting a tree because of it going without me pulling on the throttle. Mikev7 i think that I over tightened the gas gap. Thanks for the tip.