How to Clean Your Diesel Engine (DIY in 10 Easy Steps) – By FleetBarn

Diesel engines are known for their power, longevity, and performance. But like any hardworking component, they need regular care—especially when it comes to keeping them clean. A clean engine runs cooler, more efficiently, and is easier to inspect and maintain. At FleetBarn, we believe in empowering truck owners and operators with simple, effective maintenance know-how. Here’s a 10-step DIY guide to safely and effectively clean your diesel engine and keep it in top condition.

Step 1: Gather Your Supplies

Before you start, make sure you have:

Engine degreaser (non-corrosive, diesel-safe)
Plastic bags and tape
Soft-bristle brush
Microfiber cloths
Low-pressure water hose or spray bottle
Safety goggles and gloves

Step 2: Let the Engine Cool

Never clean a hot engine. Let it cool down completely to avoid burns or warping any components.

Step 3: Disconnect the Battery

Safety first! Disconnect the negative terminal of the battery to prevent short circuits or damage during cleaning.

Step 4: Cover Sensitive Components

Use plastic bags to cover the alternator, air intake, sensors, and any exposed wiring or electrical connections. Secure them with tape to keep water out.

Step 5: Dry Dust the Engine Bay

Using a brush or compressed air, remove loose dirt, leaves, and dust before applying any cleaner.

Step 6: Apply the Degreaser

Spray the engine degreaser generously over greasy and dirty areas. Focus on valve covers, the oil pan, and around the injectors. Let it sit for 5–10 minutes (check product instructions).

Step 7: Scrub Stubborn Areas

Use a soft-bristle brush to gently scrub caked-on grease or grime. Be careful around wires and seals.

Step 8: Rinse with Low-Pressure Water

Use a low-pressure hose or spray bottle to rinse off the degreaser. Avoid using high-pressure water, as it can force moisture into sensitive areas.

Step 9: Dry and Remove Covers

Wipe the engine with a clean microfiber cloth. Let it air dry, then remove all plastic coverings. Check for any trapped water or moisture.

Step 10: Reconnect the Battery & Run the Engine

Reconnect the battery terminals. Start the engine and let it run for a few minutes to evaporate any remaining moisture and check for smooth operation.

Pro Tips from FleetBarn

Clean your engine every 3–6 months depending on driving conditions
Avoid using harsh chemicals that may corrode engine components
If in doubt, consult a professional or bring your truck to a FleetBarn service partner
Always dispose of cleaning agents and oily rags responsibly

A clean diesel engine is not just about looks—it’s about performance, longevity, and safety.

Whether you're a fleet owner or an independent driver, routine DIY maintenance like this can help you spot leaks early and improve your truck’s resale value. And remember, when things get too dirty—or complicated—FleetBarn is always here with heavy-duty towing, maintenance tips, and on-road support.

Keep it clean. Keep it moving. Trust FleetBarn.