Truck Parts and Service | Heavy Duty Trucking, Aftermarket, Service Info
Issue link: https://read.dmtmag.com/i/123976
Tech Updates TROUBLESHOOTING A/C COMPRESSOR ISSUES W hen investigating electrical problems with a heavy-duty A/C compressor, Red Dot says to follow these four steps. Recreate the problem: Recreate the demand for voltage when making your diagnosis. With the engine and air conditioner running, turn on lights, wipers, radios — anything that draws from the truck's electrical system, Red Dot says. Then take a reading. Ideally, you want 13.5 volts but not less than 11.5 volts at the clutch coil. Also, look inside the cab or sleeper for an aftermarket power inverter with 110-volt AC outlets; evidence the driver may be drawing power that the truck's electrical system is unable to handle. Take a proper reading: Don't let a bad ground connection short-circuit your efforts, Red Dot says. Many clutches are grounded through the compressor casing, as evidenced by a single wire on the power side of the clutch. With a case-grounded clutch, measure the ground at SAFETY RECALLS Navistar is recalling certain model year 2013 International ProStar commercial trucks, manufactured from Jan. 24, 2012, through Jan. 2, 2013, with feature codes 29AEB and 29AEC. The axle bearing retaining nut lock snap ring may have not been installed or may have been installed incorrectly, which may result in the retainer nut working loose and possibly separating the wheel hub from the axle. Separation of a wheel hub from an axle may increase the risk of a crash. Caterpillar is recalling certain 2012 and 2014 Caterpillar CT660 heavy-duty trucks manufactured by Navistar between Oct. 31, 2011, and Jan. 23, 2013. Certain side marker lamps and/or reflective tape were not applied to these vehicles, which have a length of 30 feet or longer. Thus, these vehicles fail to conform to the requirements of Federal Motor Vehicle Safety Standard No. 108, "Lamps, Reflective Devices, and Associated Equipment." Missing side marker lamps and/or reflective tape reduces the visibility of the truck to others, which increases the risk of a vehicle crash. 12 T R U C K PA R T S & S E R V I C E | TPS0513PG012-14_Tech Updates.indd 12 the compressor body. You can try to pick up a ground on a bolt or bracket, but sometimes that bolt or bracket is the source of the bad ground due to corrosion or resistance that comes from paint, the company says. Protect the A/C system: A device that prevents a compressor failure will reduce maintenance costs and downtime. Red Dot says its ProTecht monitors refrigerant pressure and shuts down a system in case of refrigerant loss, excessive overcharge of refrigerant, or low voltage. Red Dot says its ProTecht electronic control unit was designed to monitor an A/C compressor unit and diagnose failures, minimizing downtime. Ask for help: When properly cared for, Red Dot says the compressor and clutch assembly should last the life of the vehicle. If you're seeing repeated premature failures, ask suppliers for help diagnosing the problem. The following are safety recalls issued by the National Highway Traffic Safety Administration: Volvo is recalling certain model year 20122014 VHD, VNL, and VNM trucks, manufactured from April 18, 2011, through March 14, 2013, and equipped with a horizontally mounted remote battery disconnect switch. The remote battery disconnect switch was manufactured with incorrect hardware allowing the cables to loosen. Additionally, as mounted, the cables may vibrate and chafe. Loose or chafed cables may lead to overheating of the battery cable and switch, which may result in a fire. Navistar is recalling certain model year 20112012 Workhorse Custom Chassis W42 and W62 vehicles, manufactured from July 18, 2011, through July 12, 2012, and equipped with hydraulic brakes. The brake fluid level indicator (FLI) may not properly detect a low brake fluid level situation and warn the driver. Without a warning, the driver may be unaware that the brake fluid level is low. A low brake fluid level may reduce the available braking force, which could lengthen the required stopping distance and increase the risk of a crash. Fontaine Trailer Company (Fontaine Heavy-Haul) is recalling certain model year 2013 Renegade LX40 and LXT40 low-bed trailers manufactured between Aug. 2012 and Nov. 2012. The combo eye plate that connects the gooseneck portion of the trailer to the deck portion of the trailer may crack and ultimately fracture and thereby fail to maintain the load carrying capabilities as designed. In the event of a combo eye plate crack and failure, the deck of the trailer could tilt and impact the highway, stopping the vehicle unexpectedly, increasing the risk of a crash. UD Trucks is recalling certain model year 20112013 UD2600 and UD3300 trucks equipped with Allison 3000RDS automatic transmissions. The oil cooler hose clamp retaining rings may fail. If the retaining ring fails, the oil cooler hose may leak, leaving a large deposit on the roadway, which may present a hazard to other vehicles. If any of the oil sprays onto hot engine components, there would be an increased risk of a vehicle fire. continued on page 14 May 2013 4/18/13 3:26 PM