If you watched the video by Invisible Speed RC on how to tune a nitro RC engine, then you already know how the carburetor works. If you need a refresher, watch the video below which is an excerpt from the same video about how a carburetor works.
Maintaining the carburetor
There really isn’t any maintenance required for a carburetor under normal operating conditions. Simply check it before you run your nitro RC to confirm it is secured to the engine and hasn’t changed positions, which will mess up your throttle linkage. It is also good to remove the air filter and confirm that the throttle end points and trim are correctly configured for full throttle, neutral, and full brakes.
Over time, you may notice that your engine is becoming more difficult to tune or the tune keeps changing as you run your nitro RC. When this happens, do a full rebuild of the carburetor so you can clean, inspect, and replace any worn parts. The most common issues with carburetors are a torn o-ring or dirt blocking one of the passages. Clean your carburetor with compressed air and denatured alcohol, rubbing alcohol, or nitro cleaner.
Here’s a great video by theBug 404 on cleaning and rebuilding a carburetor:
If you’re interested in what Traxxas has to say on rebuilding a carb, read How to rebuild the TRX Racing carburetor.
Pretty much every carb is the same with only slight variations. Definitely watch the video above so you don’t make any rookie mistakes, like tightening down screws too hard. If you ever get lost during a rebuild and don’t know where something goes, pull up the exploded view for the carburetor and you’ll have it back together in no time.
Maintaining the air filter
One of the most common ways nitro engines are destroyed is by not properly maintaining the air filter. The air filter (aka air cleaner) traps dirt and dust so it doesn’t enter the carburetor or engine. The air filter should be cleaned and oiled after every 1 hour of run time, which is typically 2-4 driving sessions. If you are running your nitro RC in very dusty conditions, consider cleaning and oiling the air filter after every 30 minutes of run time.
How to clean and oil an air filter
- Disassemble the air filter to separate the foam filters from the housing.
- Clean the housing using or soapy water. Set it aside to dry.
- Clean the foam filters (most come with two filters) with soapy water. Rinse the filter with water and squeeze out as much water as possible. Set it aside to dry.
- Once the foam filter is dry, apply air filter oil to the inner filter only. Apply the oil in drops even spaced around the filter and then rub in the oil to saturate the filter. If you don’t want to get your hands dirty, you can put the filter inside a plastic bag for this step.
- Reassemble the air filter and secure it to the carburetor.
A few notes on maintain an air filter:
- Make sure the foam filters are completely dry before oiling and reinstalling.
- Only oil the inner filter. If you oil the outer filter, it will attract dirt and will need to be cleaned more often.
- Use actual air filter oil meant for foam filters. There are a number of products made specifically for nitro RCs, but any filter oil that is intended for foam filters works well. These other air filter oils are typically made for dirt bikes.
Additional Info
- How To Clean and Re-Oil the Air Filter (Traxxas)
- how to clean a nitro rc air filter cheap and easy! (thebug 404 on YouTube)