How to replace belt tensioner on a 1989 Ford Tempo.

You use a special tool to move the belt tensioner to release tension on the belt. Sometimes you can use a regular wrench if you have enough room.
Make sure you have a diagram or draw one of the routing of the belt before you remove it so you know how to put the new one back on.

it would seam that it looks like its on right but not correctly over crankshaft ,that's the one that makes it move if in dough try autozone library

check belt tensioner to make sure it keep the belt good and tight that's normally the problem other than it just being a bad belt but always replace the belt whether you replace the tension-er or not.

you have to check diagram an there is usually a tensioner you have to put a long wrench on it pull to get belt off then the same way to put on just find the tensioner

Make a simple drawing of the routing of the belt. or try to take a digital picture for reference on installation. Typically, one side of the belt has groves, and the other smooth. The pulleys will be grooved or smooth to match the side of the belt they are supposed to contact, don't put the grooved side of the belt on a smooth pulley or vise versa. There should be an "idler pulley" which applies pressure to the belt to keep it tight. This idler maybe manual or automatic. A manual pulley will usually have an adjustment bolt running perpendicular to the pulley face. You will loosen the bolt in the middle of the pulley a bit, then loosen the adjustment bolt until there is enough slack in the belt to remove it from at least one pulley, the the whole belt should be easy enough to remove, barring any engine mounts in the way. If an automatic (Sprung) tensioner is used there is usually a way to get a 3/8" or 1/2" drive breaker bar onto the pulley and actually "flex" it so that the belt tension is relieved. You will need to hold pressure on the tensioner until the belt is removed from a pulley, this may take another set of hands. Installation is the reverse of removal. Old automatic tensioners can sometimes get stiff, may need to be replaced, or removed and lubricated until it actuates smoothly. Check all the pulleys very carefully to insure the belt is aligned properly, before starting the engine. many a belt has been destroyed when someone started the engine with belt misaligned. Have fun.

Ask your repair person or ur ford dealer

serpentine belt tensioner tool is best because you have such a small amount of space between the tensioner and the vehicles body/frame.

I think the belt for the a/c runs only the a/c compressor. There is an automatic belt tensioner on a separate pulley. So, if you just have the a/c pulley and the tensioner, you can just leave the belt off.
the alternator has it's own belt.

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Having the harmonic balancer replaced today on my 94 topaz, rubber has broke in balancer