Basic Diesel Engine Maintenance Checklist

Changing the Lubricating Oil

Lubricating oil keeps parts moving smoothly, draws away heat, and prevents carbon deposits developing. Check your owner’s manual for the proper type of engine oil, then check your dipstick every few weeks to make sure you aren’t running low. At set intervals, you’ll need to have all your engine oil replaced.

Changing the Air Filter

Air filter setups are mostly the same with diesels as they are with gas-powered vehicles. Once you pop the hood, you’ll find them located within the cold air collector box. Check your owner’s manual for recommended replacement intervals, then switch out air filters accordingly.

Changing the Fuel Filter

Diesel engines have two fuel filters. There’s a primary filter between the fuel tank and the engine and a secondary filter near the engine to provide a final cleaning. Both should be easy to change — you simply unscrew the old filter, moisten the new one’s gasket, then screw it into place. Just make sure you bleed air bubbles out of the fuel system to get a new supply of fuel circulating.

Bleeding the Fuel System

Air in the fuel can cause starting problems, and air can get in when you change the filters or run out of fuel. You’ll then need to bleed the engine by opening the fuel supply valve and using the manual fuel pump. Pump until you get clear fuel with no bubbles.

Draining the Water Separators

Diesel fuel gets contaminated with water more easily than gasoline, so diesel vehicles usually feature a water separator located on or near the fuel filter. They’re self-cleaning, but most need to be drained manually. Simply open the drain valve and empty the water from the collection chamber.

Diesel Maintenance vs. Gasoline Maintenance

Many drivers and fleet operators will compare gas vs. diesel when they are looking for a new vehicle, and it’s not hard to see why. After all, just about every driver wants to lower their operating costs and spend less time in the shop. Although gasoline engines have some advantages—they’re great for quick acceleration—many find that diesel engines are easier to maintain. Here’s what you should keep in mind:

• Diesel engines compress and fuel to a much higher degree than their gasoline-powered counterparts. As a result, diesel engines don’t require spark plugs. Gasoline engines need to have their spark plugs replaced every 30,000 to 100,000 miles.
• Because diesel engines are able to operate without the use of spark plugs (and a variety of other small, sensitive components) they tend to be longer-lasting and more durable. A diesel engine can last for 500,000 or even 1,000,000 miles with proper maintenance, whereas gas engines tend to have an upper limit closer to 200,000 miles.
• Here’s the trade-off: parts for diesel engines tend to be more expensive and harder to find than parts for gas engines. This means that when you do need serious diesel maintenance, you might end up spending a little bit more than you’d spend on a gas-powered vehicle. But for many drivers, this is a small price to pay for fewer trips to the service center.
• Recommended service intervals vary between gasoline and diesel engines, and in general, the heavy-duty oiling systems in diesel vehicles allow them to go longer between oil changes. However, you should follow all recommendations in your owner’s manual.

Visit Badger Truck & Auto Group in Milwaukee for Diesel Maintenance

Drivers from Madison, Waukesha, and beyond turn to our service center for diesel engine care tips. Schedule servicing today or feel free to contact us directly for further advice.