Careful maintenance keeps repair madness at bay

Reefer-unit service intervals vary from 1,000 to 3,000 hours. Late-model units use a combination full-flow and bypass filter and CJ-4 oil, allowing the longer interval. Older units can be retrofitted with new oil- and fuel-filter mounts, new oil and new filters to permit the longer 3,000-hour interval.

At the CSTK dealership in Vineland, N.J., Technician Jeff Vertolli, Service Manager Gary Smith and Director of Service Operations Don Peterson ran us through a complete servicing process for a late model SB series design with a 4-cylinder Yanmar direct injection diesel. “Unit life is greatly affected by proper oil and oil filter changes, as well as fuel and air filter changes,” Peterson says.

A- To change the oil, make sure the engine is hot, shut it down and slide a hose onto the brass drain valve.

B- Place a drain pan underneath and rotate the valve a quarter turn with a wrench or screwdriver. At the same time, spin the oil filter off. Make sure the gasket comes off with the filter. Lube the gasket on the new filter with clean engine oil and install the filter hand tight.

C- Rotate the drain valve back to the closed position, then fill the crankcase with oil by removing either the yellow filler cap or orange dipstick cap. Start the engine to circulate the oil. Make sure you get full pressure and that there are no leaks. Jeff Vertolli says leaks at the dipstick cap in the crankcase often can be prevented by properly cleaning the circular seat where the dipstick cap seals.

D- Change the spin-on fuel filter and prime it with clean fuel. Peterson says the best procedure is to pour the priming fuel down the outside holes so it will be filtered before entering the system. There is also a strainer by the fuel pump that should be cleaned at this time. Also change the air cleaner, located just to the right of the fuel filter. Loosen the hose clamp and disconnect the intake hose, then twist the filter counterclockwise to unlock it and pull it off. Use a quality replacement filter whose filter and cap are sealed. Twist the new filter on tight, then install the hose and tighten the clamp. Vertolli recommends twisting the hose counterclockwise just before tightening the clamp to “pre-load” the filter to help keep it on tight. Record the date and engine hours when changed on the marking area provided.

E- Next, inspect the drive belts for condition and proper tension. If glazed (smooth) or cracked, replace them. The generator and water pump belt is tightened by loosening the generator mounting bolts and pulling on the generator so the bolt in the adjusting slot moves upward. Hold in position and tighten all bolts. Check the belt tension for the two condenser-radiator fan drive belts. To adjust these belts, loosen the two bolts at the rear and two at the front of the gearbox. Pull the gearbox outward gently to tension the belts, hold it in place and tighten the mounting bolts. Belts that are too tight can ruin the water pump, generator or gearbox bearings. Remove the fill plug at the top and drain plug on the bottom of the gearbox and drain the lube into a catch pan. Once drained, replace the drain plug, refill by emptying a tube of replacement lube into the filler port and replace the plug.

With the engine below operating temperature, check and, if necessary, refill the radiator overflow tank on the right side of the unit at the top with ELC (red) coolant. Coolant should be changed at recommended hours and the extender poured in halfway through the cycle.

F- Start the unit and run it on high-speed cool. Check for adequate refrigerant by looking at the ball in the view port on the receiver tank. The ball should be floating on liquid refrigerant.

G- At the same time, check the oil level on the front of the view port in the compressor crankcase. The oil level should be at least one-fourth of the way up from the bottom of the sight glass.

Many additional details should be checked, from inspecting wiring ties to draining the fuel tank to remove water and cleaning out a blocked tank vent. Vertolli recommends having the unit’s refrigerant charge and operating pressures checked by a licensed refrigerant technician every 6 months. This will keep the unit performing at its best and minimize the cost of repairs.

Special thanks to CSTK Executive Vice President Turner McDonald for arranging this visit.