How to Start your RC Car

You're frustrated, all hot and bothered, you've pulled on the starter so many times that your fingers are sore, so why won't the stupid thing start?

This is a common situation for those of us getting into rc cars so lets take a moment and go back to the basics. We'll go through the 3 most common causes of a failure to start and after that your speed machine should start for you every time assuming its in otherwise good shape.

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1. PRESSURE CIRCUIT

This is themost common reason why rc cars won’t start and can also be the reason why cars, will stop all of a sudden.

So what is the pressure circuit? It’s the sealed circuit between engine, muffler and gas tank. The pressure is created from the engine's combustion. This pressure is passed into the muffler, and then passed into the fuel tank. That pressure then drives fuel into the engine where it all starts over again. It’sabsolutely critical e to have an intact and well-sealed pressure circuit.

The easiest way to find a leak is to look for wet areas on the car which is why it’s important to keep your car clean. If it’s covered in dirt, all soaked in fuel it’s virtually impossible to tell where it’s coming from. So look for the areas that are wet with fuel which might be anywhere. Look at the fuel tubing, especially the connections with the carbi’, muffler and tank. If there’s a split you’ll see a wet area below it, replace or cut off the end of the tubing with the crack.

Look around the engine too, if it's wet you could have a loose head, which will need to be tightened. Go over the system checking for leaks and seal them up. Remember to check the cap of the tank too and ensure there's a little pop when you open it. If not check that the O-ring is tight enough to give a good seal.

2. FUEL INTO THE ENGINE

This may seem obvious but it’s one of the common reasons rc cars won’t start. The easiest way to get fuel into the engine is to put your finger over the muffler outlet and pull the starter a few times until you see fuel move into the engine. You'll need to release the pressure between pulls. You can do the same with a roto-starter or bump-starter. Another way is to disconnect the tubing from the muffler and blow into it until the fuel travels into the carbi’. This is not such a great method as the fuel does not taste nice (!) and you can get moisture into the system.

If the engine seems well primed but still won’t start it may not be getting fuel because of dirt blocking the needle valve. To clean it, take off the tubing and unscrew the needle valve and blow compressed air through the carbi’ from the “fuel in” side. This will blow any bits out of the system. If you don’t have a compressor use a syringe filled with fuel or methylated spirits to do the same job. Be careful not to flood the engine.

If the fuel just will not suck into the engine no matter how many times you pull on it, try taking the air filter off, putting your finger over the carbi outlet and then pulling on the starter until it’s primed. If fuel is still not reaching the engine you probably still have a problem in your pressure circuit, so you’ll need to go back over it again.

If the pressure circuit is good and there’s no dirt in the carbi’ then it may be that your piston and sleeve are worn to the point where there is no compression generated. This is the time to go and talk with the guys at your local hobby shop about a new piston and sleeve.

3. THE GLOW PLUG

Another common reason why your engine won’t start! It’s easy enough to check, simply unscrew the plug from the top of the engine and pop it into your glow starter. If there is a nice healthy glow then all is well. If not then obviously it needs replacing.

If the plug looks intact but has a weak glow just be sure that your glow starter is properly charged. If your car is starting OK but stops or falters when you disconnect the glow charger then you have a dodgy glow plug and should replace it anyway.

NOW IT SHOULD START!

If you’ve made sure of these fundamentals and the needle settings are back to the factory settings then there is no reason why your car should not start. We’ve fixed many cars over the last few years and these are the steps we go through, and so far there hasn’t been a car that we haven’t been able to start.

I hope this helps you avoid the frustration and blisters that I’ve suffered at the hands of many a stubborn two stroke. Have fun and good luck!

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