Gearing Up for Timing Belt and Chain Work
Timing belts are a maintenance item on engines that have them, but what about timing chains? On most overhead cam engines that use a timing chain to turn the cams, there’s usually some type of chain tensioner or adjuster to keep the chain tight and to compensate for stretch as the chain ages. But on pushrod V6 and V8 engines, there is no chain tensioner to compensate for chain stretch. Consequently, after tens of thousand of miles, the chain loosens up, starts to make noise as it rattles against the front cover, and causes cam timing to retard. At this point the timing chain needs to be replaced.
A/C Update: The Future of Cool
Editor Ed Sunkin returns from the Mobile Air Conditioning Society Worldwide trade show and convention in February, 2009, with details on the possible future of the U.S. refrigerant segment of the industry — HFO-1234yf. This refrigerant provides a very low global warming potential and many new service and sales opportunities.
Tech Tip: Taking Advantage of an On-Car Lathe
Well-maintained bench and on-car lathes can both do an excellent job of machining rotors. However, according to advice from the new Bendix Answerman, Chuck Kennedy, knowing when and how to use an on-car lathe can help eliminate wasted hours and extra work while also providing more accuracy and a better finish ….
Timing Tools
Before you replace a timing belt, chain or gear set on some engines, you will have to look up the timing reference marks. Some engines have multiple timing marks that can cause confusion if you don’t know which ones to use or how to line them up. Many engines also require special tools when changing
Tech Tip: Steering Position and Yaw
The Electronic Stability Control (ESC) program uses the Anti-Lock Brake System (ABS) and Electronic Throttle Control (ETC) to maintain vehicle stability in a cornering maneuver. The ESC program requires the communication between the Engine Control Module (ECM) and ABS controller. This communication takes place on the Controlled Area Network (CAN) buss of the vehicle. The program uses input from the following sensors: steering wheel position, throttle pedal position, throttle position, engine speed, brake switch, wheel speed, yaw and ….
Tech Tip: Drivetrain Noises and Wheel Bearing Replacement
One of the toughest challenges we face as import specialist techs is noise complaints. These aren’t necessarily difficult from the technical or nuts and bolts perspective as much as from the diagnostic process.
Tech Tip: Diagnosing Malfunctioning Jeep Instrument Cluster
The same two-wire CCD BUS that Chrysler has been using for years on its cars is now being used on Jeeps and trucks, giving today’s Jeep Wrangler a new level of sophistication. If the instrument cluster doesn’t work, first determine which gauges don’t operate or if the whole cluster is down. I like to start testing with the printed circuit board self test ….
Steering Position and Yaw
Driving skills and Electronic Stability Control One of the first things a novice driver asks is: “Do I turn into the skid or away from it?” With Electronic Stability Control, this decision is made for us. When a vehicle begins to skid during a cornering maneuver, the skilled driver steers into the direction of the
Tech Tip: What’s New in TPMS?
The increasingly hot topic of Tire Pressure Monitoring Systems (TPMS) is very controversial yet compelling. TPMS brings about confusion and aggravation, but more importantly, opportunity. Adding to the TPMS frenzy is loads of information. This article will discuss a couple of new issues within TPMS that you need to be aware of ….
The Ins and Outs of Indirect and Direct TPMS
This is the year of the TPMS (Tire Pressure Monitor System). It’s been coming for some time. In response to a rash of highly publicized rollover accidents caused by tire failures on SUVs, Congress passed a law called the TREAD Act in 2000 which required all vehicle manufacturers to have TPMS on all their cars