Diesel Engine Maintenance Checklist

Mechanic Working on Diesel Engine_41256309

There’s a reason why Northern Chicago drivers continue to choose diesel engines: they offer superior performance that lasts. However, that doesn’t mean these engines don’t require routine maintenance to function at their best. If you’re wondering how to care for a diesel engine or a commercial vehicle in general, Lynch Truck Center has you covered. Check out our diesel engine maintenance checklist below to ensure these important auto services are being performed.

Keep Up with Oil Changes

Oil changes are often overlooked, but truthfully, they’re invaluable. Fresh oil helps lubricate the engine’s moving parts, absorbs heat, and reduces carbon deposits. To learn more about which oil is right for your truck’s diesel engine, as well as oil change frequency for your truck, check your owner’s manual. You can also check the dipstick every few weeks and top-up if you’re running low.

Replace the Air Filter

Air filters tend to operate similarly, whether they’re connected to a gas-powered or diesel-powered engine. You can usually find them in the cold air collector box. For more information on how often to replace an air filter in a diesel engine, check your owner’s manual. Once you know the recommended replacement interval, you can switch the filter out when it’s time.

Replace the Fuel Filter

Diesel engines have two fuel filters. The primary filter is located between the fuel tank and engine and the secondary filter is located near the engine. You shouldn’t have problems changing either filter; simply unscrew the old filter, wet the new filter’s gasket, then secure the new filter in place. Don’t forget to bleed the air bubbles out of the fuel system to make sure a fresh stream of fuel is moving.

Bleed the Fuel System

Air in the fuel system can lead to issues, such as a lack of fuel flowing into the combustion chamber. Air can enter the fuel system when you change the filters, which is why bleeding the fuel system is an important step. To bleed the system, you’ll need to open the fuel supply valve and use the manual fuel pump. Use the pump until there are no bubbles in the fuel.

Drain the Water Separators

Unlike gasoline, diesel fuel becomes easily contaminated with water. For this reason, diesel trucks include a water separator, which can be found near the fuel filter. The water separator cleans itself usually, but you’ll need to drain it every so often to keep the diesel fuel clean. Open the drain valve and empty the water. It’s that easy!

Schedule Diesel Engine Maintenance at Lynch Truck Center!

Drivers from Milwaukee and Racine can rely on the service team at Lynch Truck Center for expert diesel engine maintenance. Schedule a service appointment online or contact us if you have questions about our diesel engine maintenance checklist above. While you’re here, be sure to ask about our service and parts specials!

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