Is your RC car stalling when you hit the breaks? Does it want to take off while idling?
There could be one of several things wrong and is most likely the clutch if it stalls when you hold it still. We’ll still explore all options.
We’ll start our process of elimination by checking the easiest things first.
- Check the idle screw. Make sure the idle screw is set properly. Not the mixture screws. The idle screw is on the front of the carb and controls the throttle valve’s minimum opening. There should be about 1/16″ gap in the carb while throttle is closed. This can vary some. Make sure it idles slowly with the tires off the ground.
- Make sure high and low speed needles are set properly. If you aren’t sure how to set them, check out our Redcat Racing Pitstop how-to video series for nitro vehicles.
If all checks out, we’ll move on to the clutch.
- With the engine off, roll the vehicle on the ground. Does it roll freely? If not, the clutch may be sticking. The clutch bell (gear on the end of engine) should spin freely and easily.
- Remove the engine
- Remove the clutch bell by removing the screw or clip on the end of the clutch bell where the bearing is.
- Slide off the clutch bell.
There are a couple things to check here.
- Check the spring. If the spring is broken or has come disconnected it will engage the clutch too early, not allowing the vehicle to idle still.
- Check the clutch shoes. The clutch shoes may become hot from excess slip and melt to the inside of the clutch bell. Remove the shoes and replace if destroyed. If salvageable, lightly sand off any rough, black, or shiny area with 400 grit sand paper. Also sand the inside of the clutch bell removing any glaze that is present. Sand lightly. The glaze on the shoes and inside of the clutch bell will cause the clutch to slip, which will eventually result in an over heated clutch.
- Reassemble the clutch with spring.
- Reinstall the engine using medium thread lock on the mounting screws.