Charley Helvy

Automotive Expert

Charley Helvy is an Automotive & Diesel Expert based in Avondale, Arizona. He is the founder of Charley’s Garage, an educational YouTube channel focusing on simple videos for automotive and truck enthusiasts. He has over 31 years of experience in the automotive world, and is a Diesel Instructor at the Universal Technical Institute. He offers training on gas and diesel engines on his YouTube channel, along with other DIY and explanation videos for beginners and enthusiasts alike. In 2024, he published a complete guide on Emissions Systems in Automotive and Diesel Vehicles.

Education

  • Bachelors of Science, DeVry University, Technical Management
  • Associate's Degree, Community College of the Air Force, Applied Science in Vehicle Maintenance
  • Graduate, Air Force Vehicle Maintenance Training School
  • Certificate of Completion, Diesel Mechanics, Oklahoma Central Technology Center

Certifications & Organizations

  • Certified Automotive Service Excellence (ASE) Master Heavy Truck Technician
  • Certified Automotive Service Excellence Auto Technician
  • Certified Automotive Service Excellence Truck Mounted Equipment Technician

Favorite Piece of Advice

For Vehicle Technicians: if you are not very curious about how things work, you may be pursuing the wrong career path. For fellow Auto/Diesel educators: do not forget how much we didn't know when we first started. Practice patience.

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Forum Comments (2)

Tips and tricks for buying a used car?
1. Know your budget for the car. Do not base your budget on the car and then spend what you cannot afford.

2. Identify what is important to you in a car. Is it fuel mileage, large family capacity, ability to carry stuff, tow capacity, or style? Then, do research to find makes and models that fit your interests.

3. Once you identify the car you want, do some research before talking to the seller. I highly recommend a carfax report to see if there have been any accidents. Check websites to see what similar cars' price points are to make sure this car is not too high or too low (both are suspect). When you do talk to the seller, ask about maintenance. Has the car had regular oil changes? Have they kept receipts? Is the car titled properly with no accidents?

4. Do a very good visual inspection and if you have a family member who is an auto tech ask them to come along. Any issues could be used to negotiate the price. Some things to look at: Check the condition of the tires, are they worn and need replacing? Check the interior for damaged seats, headliners, dashboard, and lights. Turn the car on and see if it has a check engine light on. When you start the car, is it easy to start? While it is idling, is it smooth or surging? Check the air conditioning while it is running and do a light check. Most people don’t look underneath the car, but rust or fluid leaks on the undercarriage can indicate that a car is in poor condition. Checking for rust is especially critical if buying a classic car.

5. Just because you find a few minor problems doesn’t mean you can’t make an offer, just ask the seller if they are willing to come down and give them the list of things you found wrong. In many cases, the seller might be willing to fix those issues themselves or come down on the price enough for you to pay for the repairs. Keep in mind the seller might have already been aware of any issues you found and has already accounted for that in their price. In that case, it becomes your decision to buy or keep looking. Good luck with the car hunt!
What's good mileage for a used car​?
There are lots of variables to consider when buying a used car. First, evidence of regular services is super important before looking directly at the mileage. For example, if I was buying a Lexus SUV from a person and it had 80,000 miles on it, I would pay a lot less if there were no records of Lexus performing periodic services on it. If that same car was at the Lexus dealership with the same mileage and they showed me records that the previous owner kept up with the recommended Lexus maintenance schedule, I would be willing to pay a higher price.

The overall brand resale value also has an impact. Honda has a reputation for having higher resale values at higher mileages than other manufacturers. I recommend doing some research to look at reliability statistics for the manufacturer and include that in your mileage considerations. Next, look at the engine type. Diesels are built for strength and longevity so a mileage of 50,000 + wouldn't be as concerning for a diesel engine as it would be in a gasoline car.

Bottom line: I would say be wary of cars with over 50,000 miles on them, but don’t be scared of going over 50k if some of the factors I mentioned above fall in line.

Q&A Comments (8)

What's the best gallon capacity for an air compressor?
When determining the appropriate gallon capacity for an air compressor, consider your intended use. For home use, opt for a one- to two-gallon compressor available at stores like Lowe's or AutoZone. These are suitable for quarter-inch or half-inch drive air tools. Conversely, for mobile applications such as service trucks requiring ample compressed air, aim for a minimum of a 10-gallon capacity compressor. This larger capacity unit offers greater capability, albeit at a higher cost.
Are there any other ways to clean an intercooler?
You could also consider flushing your intercooler with water. Avoid high-pressure sources like those at car washes, as excessive pressure may damage the intercooler. Instead, use a regular water hose at the inlet, allowing water to flow through the cooler. Ensure sufficient time for drainage before reinstallation. This process helps dislodge and remove contaminants from the intercooler, maintaining optimal performance.
How do I start a semi-truck?
Starting a semi-truck is similar to starting a regular manual-transmission vehicle. First, ensure the transmission is set in neutral, depress the clutch pedal, and set the parking brake. Then, turn the key to start the engine. After starting, release the parking brake while keeping your foot on the brake pedal and the clutch pedal depressed. Next, select a gear gradually, release the clutch pedal, and you're ready to drive. The starting process resembles starting a standard automobile but on a larger scale.
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