12.3 Preventive Maintenance Intervals

Lubricating Oil: – Check the oil level daily with the engine stopped. If the engine has just been stopped and is warm, wait approximately 20 minutes to allow the oil to drain back into the oil pan before checking. Add the proper grade of oil to maintain the correct level on the dipstick. See Figure " Oil Dipstick" .

All diesel engines are designed to use some oil, so the periodic addition of oil is normal.

Before adding lubricating oil, refer to "How to Select Lubricating Oil" “ ” in this guide.

Lubricating Oil Filter: – The oil filter is a cartridge style element and is located on the front right side of the engine. See Figure " Lubricating Oil Filter" . If followed correctly, an oil filter change can be performed quickly with minimal oil cleanup. Refer to "How to Replace the Lube Oil and Filter" “ ” in this guide.

Make a visual check of all lubricating oil lines for wear and/or chafing. If any indication of wear is evident, replace the oil lines and correct the cause.

Check for oil leaks after starting the engine.

Coolant Flush and Fill – Proper maintenance of the cooling system is vital to its performance and longevity. The cooling system must, on a constant basis, deal with cavitation, temperature/pressure variations, and continuous threats on the additive package. Once the additives have been depleted from the coolant, it will only be a matter of time until the engine components suffer. Refer to "How to Select Coolant" “ “ in this guide.

Cooling System Inspection – Inspect the cooling system as follows:

Proper maintenance of the cooling system is vital to its performance and longevity. The cooling system must, on a constant basis, deal with cavitation, temperature/pressure swings, and continuous threats on additive package. Once the additives have been depleted from the coolant, it is only be a matter of time until the engine components suffer. Refer to "How to Select Coolant" “ ” in this guide.

Coolant Inhibitor Test Intervals – Coolant inhibitor level should be checked at the intervals as listed in Table "Coolant Maintenance Intervals" in the How to Select Coolant section of this guide.

If topping off is needed, add coolant which is identical to the initial fill coolant.

Valve lash checking and adjustment should be performed per the prescribed under the proper service category for the engine, refer to "Scheduled Intervals" “ ” in this guide. All three service categories (Severe, Short Haul, and Long Haul) require a “first time” valve lash adjustment at a shorter interval. After the initial adjustment, all others are based on the same mileage intervals. Refer to "Maintenance Tables" “ ” in this guide. Proper valve lash clearance allows the engine to produce the best possible performance with the lowest emissions. Valve lash adjustments should be performed by an authorized Detroit Diesel maintenance or repair facility.

Belts should be neither too tight nor too loose. Belts that are too tight impose extra loads on the crankshaft, fan and/or alternator bearings, shortening both belt and bearing life. Excessively overtightened belts can result in crankshaft breakage. A loose belt will slip and generate excessive heat that may cause damage to the belt and accessory drive components.

Belt Replacement – Drive belts (V and poly-V) should be replaced every 2,000 hours or 100,000 miles (160,000 km).

After an extended time in service, minor rib cracks may appear, usually one or two cracks per inch is considered normal. See Figure " Minor Rib Cracking" . A concern occurs when the belt ribs exhibit severe multiple cracking or “chunking”. At this point, the belt should be replaced.

Auto Tensioner – Auto tensioners are usually maintenance free for the life of the engine. However, routine inspections should be performed. Uneven belt wear can indicate a loose, wore out, or bad bearing on the auto tensioner. A build up of dirt or grime around the front bearing surface of the wheel can indicate a future bearing failure due to inadequate lubrication.

If the vehicle is equipped with a fuel/water separator located on the frame rail, follow the manufactures recommendation on draining the trapped water and priming the fuel system. Refer to "Fuel/Water Separator Prefilter Element Cleaning" “ ” or refer to "Replace Davco 382 Fuel Pro®Fuel/Water Separator Element" “ ” in this guide.

The engine uses a cartridge style fuel filter. If followed correctly, a fuel filter change can be performed quickly with minimal cleanup. Refer to "How to Replace the Fuel Filters" “ ” in this guide.

One method of determining when filters are plugged to the extent that they need replacing is based on the fuel pressure at the fuel filter housing. See an authorized Detroit Diesel repair facility to determine a clogged filter. The maximum pressure difference between the inlet and outlet of the fuel filter housing is 0.3 bar (4.0 psi).

Air Cleaner – The air cleaner element should be inspected per the scheduled maintenance or more often if the engine is operated under severe dust conditions.

Replace the element, if necessary. Check the gaskets for deterioration and replace, if necessary. If the dry type air cleaner is equipped with an aspirator, check for aspirator damage or clogging. Clean, repair or replace, as necessary.

Inspect the entire air system for leaks daily. Look especially for torn air inlet piping or boots and loose or damaged clamps. Have worn or damaged parts repaired or replaced, as required. Retighten loose connections.

Air Cleaner Replacement – Dry type air cleaner elements should be replaced after one year of service or when the maximum allowable air intake restriction has been reached, whichever comes first.

Air-to-Air Charge Cooler – Periodically inspect the air-to-air charge cooler for buildup of dirt, mud, etc. and wash off using a mild soap solution. Check the charge cooler, ductwork, and flexible connections for leaks and have repaired or replaced, as required.

The exhaust manifold retaining bolts and other connections should be inspected for leaks. The exhaust pipe rain cap should be checked for proper operation, if so equipped. With the introduction of an Aftertreatment system, the sealing of the exhaust system is critical and should be inspected regularly.

The air compressor incorporates three of the major systems of a diesel engine (air, lubrication, and coolant). Proper inspection of air compressor would include inspecting for air, oil, and coolant leaks. Due to inadequate internal sealing air compressors, when failed, can produce excessive crankcase pressure or allow an engine to ingest oil.

There is a need to periodically remove accumulated ash, derived from engine lube oil, from the filter. The ash does not oxidize in the filter during the regeneration process and must be removed through a cleaning procedure. All Detroit Diesel ATD equipped engines will illuminate a dashboard warning lamp indicating the need for ash cleaning.

The viscous vibration damper should be inspected periodically and replaced if dented or leaking. See Figure "Viscous Vibration Damper" for “Viscous Vibration Damper"

Heat from normal engine operation may, over a period of time, cause the fluid within the damper to break down and lose its dampening properties. For this reason, the viscous vibration damper must be replaced at time of normal major engine overhaul, regardless of apparent condition.

The REPTO accessory drive is an option on the MBE4000 engine. The drive provides continuous live power anytime the engine is operating. The REPTO is driven by the camshaft gear and is an integral part of a unique SAE#1 flywheel housing. All REPTO installations require a torsional coupling installed at the flange of the drive unit (i.e. hydraulic pump). The torsional coupling incorporates a rubber element designed to reduce the unwanted stresses from reaching the engine. See Figure "MBE4000 REPTO Connection Illustration" .