The next time you utilize a drive belt, Car Pulley Belt timing belt, or timing chain, you’ll likely need to loosen a tensioner pulley to remove it. Subsequent these general guidelines and specific instructions from your own owners manual or restoration manual, your belt or chain will function for the life span of your car.
Toyota and other timing belt tensioners are loosened simply by removing them from the engine. You must slowly 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 automobiles with timing chains, though some are used with timing belts. Hydraulic tensioners are powered by oil pressure from the engine essential oil pump and may press on a tensioner pulley (timing belts) or pressure slipper (timing chain). You’ll likely need the entire year, make, and model details, and you may have to use special equipment for this kind of tensioner pulley.
Typically, a hydraulic tensioner must be “reset” and locked after removing it from the engine. Take away the lock only after the tensioner, pulley, or slipper, and timing belt or timing chain are installed and aligned.
The spring maintains tension, while the hydraulic damper keeps it from bouncing under load changes. This prevents timing belts and timing chains slapping and jumping teeth and maintains drive belts from slipping and producing noise. To loosen a drive belt springtime tensioner pulley, refer 1st to the restoration manual or owners manual’s specific season, 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 stress on the belt. You will have to hold some spring tensioners while slipping on a new belt. Others may possess a locking mechanism, such as a hole for a locking pin or hex essential.
To loosen an NAI tensioner, loosen the locking nut or bolt, after that cool off the tensioner 
screw. Push the pulley toward the additional pulleys or add-ons, loosening the belt.
Spring tensioner pulleys, as the name implies, make use of a springtime to hold tension on the belt. Most, if not all, springtime tensioner pulleys are NAI tensioners you need to include a hydraulic damper. They are more technical and costly but don’t require adjustments and are less prone to user error.