Before you run any nitro RC for the first time, you need to do a thorough inspection to make sure it is actually ready to run. Here’s everything you need do to check before those you start brappin’!
Fail safes
Every nitro RC should have an electronic fail safe (usually built into the receiver) and a mechanical throttle return. Your manual should have info on how to test the electronic fail safe.
To check the mechanical throttle return, turn on your transmitter/receiver, remove the air filter, apply full throttle, and then turn off your receiver. The tension of the throttle return should return the slide in the carburetor to the neutral position.
This video shows how a throttle return spring works. Make sure you get the right spring for your carburetor (see manual for part number). You can also used multiple rubber bands to return the throttle, just test to make sure it works!
Batteries
If you bought a used nitro RC with some batteries in it, make sure they are fully charged or replace them with fresh AAs.
Throttle & Brakes
Throttle
Make sure that the slide in the carburetor opens up all the way when you apply full throttle, that it returns to neutral when you let go of the trigger, and that it doesn’t close any further when you apply the brakes. You may need to adjust the mechanical linkage, the throttle trim, and the throttle endpoints to achieve the proper function.
Brakes
Roll the vehicle on the ground and confirm it can roll freely, then apply the brakes to stop the vehicle. If you’re not getting a quick stop, look at adjusting the brakes (see your manual).
Steering
Make sure the steering trim and endpoints are set properly. If the endpoints aren’t set properly, you can stress the servo when steering to full right or left.
Suspension
Pump the shocks a few times to make sure the shocks are filled with oil and are providing some dampening. Also to quick visual check of the suspension components to see if anything is damaged.
Air Filter
If it is a brand new nitro RC out of the box, check the air filter to confirm it has been oiled. If it is a used nitro RC, unless the air filter looks spotless, give it a good cleaning and re-oil it.
How to clean and re-oil the air filter (Traxxas)
Wheels and Tires
Make sure the wheel nuts are snug. Not a huge deal if you miss this, but losing a wheel nut mid-run is annoying. If it is a used RC, check the condition of the wheels and tires, too. If they have big cracks or the hubs are starting to round out, then plan on getting some new wheels/tires soon.
Fuel Tank and Lines
Make sure the fuel tank and lines are clean on a used nitro RC before running it. You don’t want anything in dirty fuel system to get into your engine. Check the tank and lines for cracks and replace as needed.
Carburetor
Set the needles and idle stop screw to factory settings (see your manual). This will start the engine rich and you can tune it from there.
Not a bad idea to reseat the carburetor in the engine. Take note of the carb’s position, then loosen the pinch bolt until the carburetor is free, then re-seat it in the same position and apply firm pressure downward while tightening the pinch bolt. Don’t crank the pinch bolt too tight as you can damage the carburetor.
If you don’t know how the carburetor works, learn by watching the video below.
Engine
Make sure the glow plug is snug, but don’t crank it down too hard as it could damage the threads.
Try to turn the flywheel. You should be able to spin it freely until the piston engages the sleeve in the engine, at which point you will get a lot of resistance.
If you can’t turn the flywheel or it is stuck at top dead center, you can try applying heat to the engine with a heat gun which can free it up. If the engine looks like it has seen better days, it’s probably best to do a complete tear down for inspection and rebuild.
How to rebuild an engine (Traxxas)
Gear Mesh and Engine Mount
Check the mesh between your clutch bell and spur gear to make sure it is set properly. Once you have the mesh down, tighten down the engine mount screws, preferably with thread locker so they won’t come loose while running, which will mess up your mesh and strip your spur gear.
Screws
Check as many screws as you can to make sure they are snug. Losing screws is annoying and can also damage your RC if something falls off mid-run.
Read the Manual
I’ll leave you with the perennial advice to read the manual. I check nitro RC groups and forums on a daily basis and probably 90% of the issues posted are due to the owner failing to read the manual. It usually takes about an hour to read the manual, but will save you countless hours when troubleshooting, and maintaining your nitro RC.
Get to brappin’
You don’t have to do any of the above, but it will give you a good shot at having a successful and enjoyable first run of your nitro RC. You could go even further and inspect the entire driveline and clean the engine, but those tasks take more time and are unlikely to be an issue. If you have concerns about the transmission or engine, you can always do a full tear down after the first run.