Hello,

Yesterday I noticed my car has the origanl timing belt at 152K so I am going to replace it. I have a 97’ Civic EX, V-TEC, auto trans. In looking at the repair instructions, I don’t see anything about having to adjust the TB tension. I thought it was adjusted by a spring that holds pressure on the ball bearing idler/tensionor. However, when I was picking the water pump, belt and tensionor at the auto store, the guy told me I need to adjust the tension on the belt. Is this true and how much tension should be on it? He said I can cause premature water pump failure if I tighten it too much which makes sense but I thought it had an automatic tensionor? Thanks

 

The spring is used only to set initial tension. During operation, the tensioner bolt must be tight and the tensioner doesn't move.

Put the new timing belt in place. Leave the tensioner bolt about 1 turn loose so the tensioner can move; the spring will be pulling it into the belt. Put the pulley bolt back into the crankshaft so you can turn the engine BY HAND. Turn the engine counterclockwise (which is the direction that it normally turns) to take the slack out of the belt. Tighten the tensioner bolt. Again, never run the engine or even turn it with the starter unless the tensioner bolt is tight.

 

I agree with mk. Turn the crank pulley 5-6 full revolutions counterclockwise before you tighten the tensioner bolt. Then double check that the cam and crank timing are still correct.

 

Ok, maybe it will make more sense to me when I actually have the car apart. So I don't need to push on the tensionor and hold it against the belt while tightening the tensionor bolt? Turning the crank 5-6 revolutions will put the correct tension on the belt and then I can just tighten the tensionor bolt? I'm sorry, it just seems like the tension will only be applied by the force of the spring unless I hold the tensionor against the belt while simultaneoulsy tightening the bolt? Ron, I printed the timing belt section of the service manual in your signature but don't see anything about setting the tension. Do you have a diagram of it? Thanks for the help you guys.