[Morganhart]

I have an '89 Geo Tracker that I changed the head on. Everything has gone back together well and I replaced the timing belt and idler pulley as well. I started it up without the timing cover on to make sure everything was working, and the belt runs half on-half off the cam and crank pulleys. The tension spring is on the idler, but the tensioner bar is tightened by a bolt, so it seems redundant. I loosened the bolt and cranked it, hoping it may tension itself and I could adjust it. I am pretty sure it won't last when half of it doesn't even sit on the pulleys. I checked pulley alignment and it is good. The belt doesn't have a directional arrow on it, but when I reinstalled it the other way, it came off instantly. Any ideas?

 

[aquanaut20]

One of the pulleys is not running square and/or the belt has been stressed...

You need to read up on the tension setting procedure....

... Philip

 

[Rhinoman]

Has the belt got the correct shaped teeth? There have been a few previous threads about this issue, a search of the forum via Google should bring them up.

 

[m000035]

Install the lower pulley (temporarily) and try it again. I bet the belt stays on and aligned.

I had this problem myself.... the shape of the lower pulley provides the front "guide" for the belt. The rear guide is the little washer (#17 in the picture below) .

If the belt doesn't have a directional arrow, install it so you can read the writing when standing in front of the motor.

NOTE: It really doesn't make any difference for the first install but after the timing belt has been used it should NOT be changed in direction... so it is good to have an indication of direction.

 

[Skyhiranger]

I have an '89 Geo Tracker that I changed the head on. Everything has gone back together well and I replaced the timing belt and idler pulley as well. I started it up without the timing cover on to make sure everything was working, and the belt runs half on-half off the cam and crank pulleys. The tension spring is on the idler, but the tensioner bar is tightened by a bolt, so it seems redundant. I loosened the bolt and cranked it, hoping it may tension itself and I could adjust it. I am pretty sure it won't last when half of it doesn't even sit on the pulleys. I checked pulley alignment and it is good. The belt doesn't have a directional arrow on it, but when I reinstalled it the other way, it came off instantly. Any ideas?

As was said, the crank pulley is what keeps the timing belt from walking off the front of the timing belt pulleys. So it sounds like your only issue is you haven't got all the pieces installed to keep the belt tracking correctly.

 

[Morganhart]

Thanks for the help Mike. It is all back together and all good to go.