I am an Affilate!

I hope you like any service or product that I recommend. :) So I am clear, I may take a share of any sales or other compensation generated from the links on this page. As an Amazon Associate I earn from qualifying purchases. Just want to say, if you use my links, I appreciate your support.

Why Is My Nitro Engine Hard to Turn Over?

If you want to know why your Nitro engine is so hard to turn over keep reading. Also. learn how to know when your engine is bad, and if it’s feasible to run in winter.

Why is My Nitro Engine Hard to Turn Over?

Here are some of the most common reasons for this:

1. Engine is Hydrolocked

If there’s excess fuel inside the combustion chamber, it can prevent the piston from moving freely. Since liquids are incompressible, the piston can’t move if there’s too much fuel in its path.

Solution: Remove the glow plug and turn the engine over slowly to allow excess fuel to escape. Always ensure that your engine is correctly tuned to prevent over-fueling.

2. High Compression

Nitro engines depend on compression to ignite the fuel mixture. However, if the compression is too high, it can make it hard to turn the engine over.

Solution: Double-check the glow plug and ensure it’s the correct type for your engine. Additionally, inspect the head gasket for damage or improper installation.

3. Engine is Cold

A cold engine can be harder to turn over due to the increased viscosity of the lubricants inside.

Solution: Pre-warm the engine using a heat gun or an engine heater. This softens the oil and makes the internals move more freely.

4. Old or Degraded Fuel

Using old or degraded nitro fuel can cause starting issues, as the fuel may not ignite properly.

Solution: Always use fresh nitro fuel and store it in a cool, dark place. Ensure that the fuel cap is securely fastened to prevent contamination and evaporation.

5. Bearings are Damaged or Dirty

Bearings that are damaged or have collected dirt can increase resistance in the engine’s rotational parts.

Solution: Clean or replace the bearings. Regularly maintain your nitro engine by cleaning it after each use to prevent dirt accumulation.

6. Piston and Sleeve Fit

Over time, the fit between the piston and the sleeve can become too tight, especially if the engine has recently been rebuilt.

Solution: Allow the engine to break in properly. A new piston and sleeve might be tight at first, but they should loosen up after a few runs.

7. Residual Oil and Gunk

After running, oil and other residues can accumulate in the engine, causing it to become sticky and hard to turn.

Solution: Disassemble the engine and clean the internal components using nitro engine cleaner or denatured alcohol. Avoid using aggressive solvents that might damage the engine parts.

8. Damaged Internal Components

Cracks, bends, or other damages to the internal components, like the conrod or crankshaft, can impede the engine’s ability to turn over.

Solution: Inspect the engine internals for any visible damage. Replace any damaged parts before attempting to start the engine again.

How Do I Know if My RC Motor is Bad?

INJORA RC Motor 550 Brushed Waterproof Motor for 1/10 Short-Course Truck Slash VKAR 10SC HPI HoBao HuanQi 727(12T)

Click here for the price, on Amazon #Ad

Here is what you need to look out for:

1. Visual Inspection

Begin with a straightforward visual inspection:

  • Physical Damage: Check for any visible signs of wear, cracks, or other damage.
  • Burnt Smell: A burnt odor often indicates that the windings might have overheated, which could mean the motor is damaged.
  • Debris: Ensure there isn’t any debris lodged inside the motor. Small stones, dirt, or even bits of grass can hamper its performance.

2. Sound Check

Turn on your RC model and listen carefully:

  • A smoothly running motor will usually produce a consistent hum or whir.
  • If you hear grinding, stuttering, or any irregular noises, it could suggest that something is amiss.

3. Performance Decline

Noticeable declines in performance can be a clear sign:

  • Loss of Power: If your RC vehicle or aircraft seems less powerful or is struggling to achieve its usual speeds, the motor might be the culprit.
  • Overheating: If the motor gets hotter than usual after a short period of use, it could be malfunctioning. Always remember to touch carefully to avoid burns.

4. Unresponsive Controls

If your RC model fails to respond or responds slowly to throttle adjustments, this can suggest a motor issue.

5. Battery Drains Faster

If you observe that the battery depletes quicker than usual, it might mean the motor is drawing more current due to internal issues.

6. Physical Vibrations

Excessive vibrations can indicate an unbalanced motor or one where the bearings are worn out.

7. Using Measurement Tools

For those who want to be thorough:

  • Multimeter: By using a multimeter, you can check the resistance of the motor’s windings. If it reads infinity (or an open circuit), one of the windings may be broken.
  • Tachometer: Measure the RPM of the motor. If it’s running slower than its rated speed (taking battery charge into account), there might be a problem.

What to Do if You Suspect a Bad Motor?

If after your assessments you believe the motor is faulty, here’s what you can do:

  • Consult the Manufacturer’s Manual: Sometimes, there may be specific troubleshooting steps provided.
  • Seek Expert Advice: Before making any decisions, it might be wise to consult with fellow RC hobbyists or professionals.
  • Replacement: If your motor is indeed bad, it might be time to get a new one. Ensure that the replacement is suitable for your RC model’s specifications.

Can You Run a Nitro RC Car in the Winter?

Yes, but there are considerations and precautions to keep in mind. Such as:

Temperature Considerations:

  • Engine Start Difficulties: Nitro engines can be a challenge to start in cold weather. The oil in the fuel tends to be thicker when cold, which can make it hard for the engine to turn over. A pre-heater or a warm environment to start the engine might be necessary.
  • Tuning Issues: Nitro engines rely on a fine balance of air and fuel mixture. Cold air is denser than warm air, which can cause the engine to run lean (too much air in relation to fuel). This can cause overheating or even damage the engine. Regularly checking and adjusting the tuning is crucial in winter months.
  • Battery Life: Cold temperatures can affect the performance of the onboard electronics and the starter battery. Expect reduced battery life in colder conditions.

Material and Structural Concerns:

  • Plastic Brittle Nature: Cold temperatures can make the plastic parts of your RC car more brittle, leading to an increased risk of breakage upon impact.
  • Shock Oil Viscosity: The oil in the shocks can thicken in cold temperatures, affecting the car’s suspension and handling.
  • Metal Contraction: Metal parts can contract in colder conditions, potentially causing alignment or fitment issues.

Precautions and Tips:

  • Properly Warm Up: Ensure the engine is adequately warmed up before going full throttle. This helps in preventing wear and tear.
  • Regular Checks: Frequently inspect the car for signs of wear or damage, especially after any crashes.
  • Adjust Shock Oil: Consider changing to a lower viscosity shock oil during winter to maintain performance.
  • Winter-Proofing: Use lubricants and protectants that are rated for colder conditions to keep moving parts operating smoothly.
  • Store Properly: When not in use, store your nitro RC car in a warmer environment to prevent any damage from prolonged exposure to cold temperatures.
  • Limit Exposure: If temperatures are extremely low, consider limiting your run time or waiting for a slightly warmer day.
  • Run on Clear Days: It’s not just the cold that can be an issue – wet and snowy conditions can introduce moisture into the electronics and other parts of the car. Whenever possible, run the car on clear, dry days.