The next time you utilize a drive belt, timing belt, or timing chain, you’ll likely have to loosen a tensioner pulley to remove it. Following these general guidelines and specific guidelines from your own owners manual or restoration manual, your belt or chain will function for the life span of your car.
Toyota and additional timing belt tensioners are loosened by simply removing them from the engine. You must gradually compress them in a bench vice and lock them with a pull-pin before reinstallation.
Hydraulic (not hydraulic-damped) tensioners are nearly always positioned in the timing case, mostly upon vehicles with timing chains, while some are used in combination with timing belts. Hydraulic tensioners are driven by oil pressure from the engine essential oil pump and could press on a tensioner pulley (timing belts) or stress slipper (timing chain). You will likely need the entire year, make, and model details, and you may have to use special equipment for this type of tensioner pulley.
Typically, a hydraulic tensioner needs to be “reset” and locked after removing it from the engine. Take away the lock only following the tensioner, pulley, or slipper, and timing belt or timing chain are installed and aligned.
The Car Pulley Belt spring maintains tension, as the hydraulic damper keeps it from bouncing under load changes. This prevents timing belts and timing chains slapping and jumping the teeth and maintains drive belts from slipping and producing sound. To loosen a drive belt springtime tensioner pulley, refer initial to the restoration manual or owners manual’s specific calendar year, make, and model information.
You might need a special tool, but many spring tensioners have a square hole, for a 3/8” or 1/2” breaker bar, or a hex or square protrusion for a wrench or socket. Using the appropriate tool, release tension on the belt. You will have to hold some springtime tensioners while slipping on a new belt. Others may possess a locking mechanism, like a hole for a locking pin or hex key.
To loosen an NAI tensioner, loosen the locking nut or bolt, then cool off the tensioner screw. Force the pulley toward the other pulleys or components, loosening the belt.
Spring tensioner pulleys, since the name implies, use a spring to hold tension upon the belt. Most, if not all, springtime tensioner pulleys are NAI tensioners you need to include a hydraulic damper. They are more complex and expensive but don’t require modifications and are less susceptible to user error.