You will need to tell the year, make and model. All are different.
Loosen the tensioner bolt, let the spring loaded tensioner contact the belt. Then tight the tensioner bolt.
there are two tensioners, the serpentine tensioner and the timing belt tensioner. the timing belt tensioner is behind the timing belt cover ;)
the only belt with a tensioner is the timing belt, to tighten the alt belt loosen the adjustment bolt then tap the alt back then retighten the bolt
Remove valve cover, then remove the side time belt cover. Check timing belt tension. If there's too much slack, loosen timing belt tensioner, put pressure against side of tensioner with long screwdriver, then tighten the tensioner bolt.
The timing belt tensioner is under the timing cover(you most likely have that off already). I believe it is a 14mm bolt keeping it down, loosen that bolt and remove the tensioner spring with a pair of needle-nose pliers. Don't drop the spring!
You remove the two bolts from the bottom.
The easiest way to loosen the tensioner is to use an automatic belt tensioner. This can be used on a serpentine belt which is connected to every pulley on the engine.belt.
You just need to remove the bottom cover on the side where the timing belt is. Then loosen up the bolt on the tensioner, then use pry bar then when when the belt is tight, tighten the tensioner back up. (make sure Your TDC (Top Dead Center)) ;)
Loosen the timing belt tensioner so the belt will have some slack before removing it from a 1985 Honda Civic. Remove the old belt. Install the new belt and make sure the engine is TDC.
There is only one belt, the serpentine belt. You use a wrench to loosen the spring loaded tensioner and remove and replace, there is no timing belt it has a chain.
You need to loosen the belt tensioner. There is a large bolt that needs to be loosened in the center of the tensioner pulley. Then the small vertical bolt is turned in the direction to loosen the belt. After the tensioner is loose replace the belt and retension it.
The Chev 350 and the 6 cylinder do not use a timing belt; they use a timing chain. You need to pull the front engine cover to get to the timing chain. That means pull the harmonic balancer, water pump and anything else on the front. However... they do use a serpentine belt to drive the alternator, water pump, power steering etc. To loosen the serp belt, you should be able to just loosen the tensioner.