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How to replace the timing belt in a 1991 Chev Sprint

Yet another how-to that should apply to most 1989-1991 Sprints, Fireflys, Metros, and Swifts. This was done on a 1.0L 3-cylinder, so those with the 1.3L are out of luck. Unfortunately, I didn’t think to take pictures during this procedure, but I’ll try and be as specific as possible. This was not performed on a vehicle with air conditioning or power steering. If you have either of these, there may be more steps involved. Oh, and as with all vehicle work, it may be a good idea to disconnect the battery. After all, you don’t want to lose your hand/arm/life because the car tried to start at the wrong time.


1) Remove the alternator belt. This will involve loosening the bolt at the top of the alternator where it’s connected to the bracket. If the alternator doesn’t move, you may have to use a prybar to help push it towards the engine (be careful not to place the prybar up against the brake lines or against anything else that might be damaged). There’s also a bolt at the bottom of the alternator where it’s mounted to the engine (where the alternator *should* pivot). If you’re not having a lot of success, loosen that bolt a little as well and it should be easier. Note that you don’t have to move the alternator extremely far, just enough to get the belt off.

2) Remove the water pump pulley. It is held on by 4 bolts. If the bolts are really tight, you may have to grip the pulley with vice grips to keep it from turning while you crack the bolts loose.

3) Remove the passenger side splash guard. You will have to crawl under the car for this, and may have to turn the steering wheel to the right to get at all the clips.

4) Remove the crankshaft pulley. There are 4 bolts to remove (do not remove the large center bolt) You will probably have to access them from under the car. A ratchet with a long socket (or an extension) will be best. In my case (using an extension), I could only get at 1 bolt at a time and had to rotate the crankshaft to get at all of them. Again, vice grips (or a strong assistant holding the pulley) may be helpful here to keep the pulley from rotating as you crack the bolts loose.

5) Remove the timing belt cover. This is the big black plastic cover. There are a total of 1 nut and 8 bolts (4 on each side). Keep track of which bolts go where, as some may be longer than others. There may also be wire ties that are held on by these bolts. Be sure not to lose them.

6) Set the timing. For the cam sprocket (the top one), there should be a mark on the sprocket that lines up with a little “dip” on the top ridge of the valve cover. To set the crank sprocket, you may have to replace the timing belt cover and crank pulley. In my case, the pulley had a white mark on it, and the timing belt cover had timing marks. Simply line up the white pulley mark to the “0” on the cover. Alternately, if the crankshaft sprocket has a mark on it, there may be a mark on the engine that it corresponds to. If this is the case, simply line those up.

7) Loosen the belt tensioner. There is a bolt on the tensioner pulley itself, as well as a “tensioner stud” against the tensioner plate, which must be loosened (but not removed) with a wrench. Once both of those are loose, the tensioner should be movable by pushing the tensioner plate in either direction. Push the tensioner plate, which will put the least tension on the belt, and temporarily tighten the tensioner stud to keep it from being auto-tensioned by the spring. I have included an image below, taken from a workshop manual which should be similar.
Sprint/Metro/Swift/Firefly Timing Belt Tensioner

8) If the original belt is still intact, double check the position of the timing marks on both the cam and crankshaft sprockets (they should both be lined up. if they’re not, figure out why before going any further). Remove the original belt.

9) Install the new belt. Start by slipping it over the crankshaft sprocket, running it past the tensioner, and then slipping it on the camshaft sprocket going from right-to-left, being careful not to rotate either sprocket. If either sprocket rotates, remove the belt, re-position the sprockets, and start again. There should be no slack in the belt on the right side.

10) Loosen the tensioner stud. The tensioner plate should be pulled into place by the spring, and the pulley should remove the slack on the left side of the belt. Do not tighten the tensioner stud or the pulley stud yet.

11) Rotate the cam or crank sprocket clockwise 2 complete turns. This is usually accomplished most easily by using a ratchet and socket on one of the center bolts. After the rotations, continue turning clockwise until the timing marks are lined up. Make sure that both the cam and crank sprocket line up to their respective marks. If they don’t, you are probably off by a tooth, in which case you must remove the belt, line up the sprockets, and try again.

12) Tighten both the tensioner stud and pulley bolt. Opinions vary on whether to rely soley on the tensioner spring, or to add finger pressure before tightening. I added a little bit of finger pressure before tightening mine. Rotate the cam/crank again 2 full rotations. Check again to make sure the timing marks line up, and make sure there is tension on both sides of the timing belt.

13) Assuming the timing marks still line up and the belt seems to have decent tension to it, reassemble everything.

14) If after everything’s said and done the car won’t start (or runs poorly), there’s a good chance the timing belt is off by a tooth. Take everything apart and double check. Alternately, you could have some damaged valves or pistons, although as far as I know, my own Sprint has a non-interference engine.

With all that said, good luck. As always, a workshop manual (or even a Haynes or Chilton’s manual) can be extremely helpful and may cover things more accurately, in better detail, and/or things that I may have missed.

Standard disclaimer applies. If my instructions result in any deaths (including but not limited to the death of your car), I’m not responsible.

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