TimingBeltTensionerReplacement

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The following was taken from a post by JimD

For sure read thru the manual's instructions, but I basically followed the manual and here is what I did. Keep in mind I had an entire bearing and mount ready to use. I did not need to figure out how to put R/R the old bearing on the existing mount.

Make sure you have a new t-belt on hand if the existing one has a lot of miles on it.

Also... is your 1500 engine still a stock non-interference set up?? If it has had head work done, etc, you may need to exercise a lot more caution to guard against fouling your valves and pistons.

Following a suggestion from Mac, I use a vise grips to pull the tensioner piston from the rear. Just clamp the grip onto the tail end of the tensioner spring piston and pull to the rear to release the tension on the bearing while you slip the belt off with your other hand. For me, this worked much better than trying to force the bearing backwards while also slipping the belt off. Leave the vise grips on there till you are done with the reinstall of the belt.

Here we go: Siphon the coolant from the res tank in the engine bay. This reduces the amount of AF that flows through the tensioner mounting stud when you loosen it. Remove the negative battery cable jack up the rear of the car and secure on jack stands Remove the pass side rear wheel Remove the plastic fairing in the pass side rear wheel well Remove the upper and lower t-belt covers. Using a 1.5" socket on the crank nut, rotate the engine until the cam and crank indicators line up on their respective TDC marks. This can take a couple rotations as the cam rotates twice for each crank rotation (or is it the other way round?) Remove the nut from the tensioner... there will be some AF leakage. I put a small catch pan under the car to limit the mess. Note the order of the washers and spacers. Pull the dizzy cap and note the direction it is pointing. Make a pencil mark on the dizzy case for reference if desired. Release the tension and carefully remove the belt making all efforts not to disturb the cam, crank or aux pulleys. Remove the tensioner bearing and its mount from the stud. (Here is where you may need to remove the old bearing and press on the new???) Put the mount and new bearing back on the stud and put the spacers and washers back. Leave the nut loose enough to be able to work the belt back on. Carefully replace the t-belt, again with care towards not moving any pulleys. Start with the belt around only the crank pulley and seat it into the teeth. Next put the belt onto the aux pulley keeping tension between it and the crank while engaging the teeth. Watch the rotor to be sure it does not stray, it is driven by the aux. You can rotate the aux prior engaging the new t-belt to realign the rotor if necessary Now take the belt over the cam pulley, again keeping tension from the crank to the aux to the cam. All slack should be on the tensioner side. Pull back on the tensioner spring with the vice grips and carefully slip the belt into position without disturbing the belt's teeth in the cam, aux and crank pulleys. Gently let the tensioner spring take up the slack. At this point you should check your work. The cam and crank pulleys should still be on their TDC marks. The rotor should still be pointing to the same position as when you started this project. If all this looks good, move on. tighten the tensioner nut to 33lbs sq ft. again using the crank nut, rotate the engine a 1/2 turn to allow the tensioner to take up any slack (Your cam and crank pointers are no longer aligned to their marks TDC at this point) loosen the tensioner nut and retorque to 33lbs to account for any slack from rotating the engine

Now you can button the "necessary to fire" things up (dizzy cap, neg batt cable, etc) and attempt to start the car. Don't forget you are a gallon down on AF, so just make sure the car starts and sounds OK on this first attempt. If everything goes well, top off the AF.

If the car starts and sounds pretty good, you can then set the timing if necessary. If the car won't start, you may need to go back and review what you did. If the aux pulley moves significantly while the t-belt is off your timing can be way off. If the cam or crank moved, that will also cause issues. As long as your 1500 is stock, you should not have any interference issues.

Once you are happy with how it is running, put all the covers and guards back in place. Don't forget to open the heater valve occasionally and purge your radiator for a couple days just in case you got some air in the system during this project.

Good luck Larry.... hopefully I have not put anything stupid in this list of instructions. I am sure I will hear about it if I did! __________________ JimD


and a little addendum from LarryC regarding replacing the bearing on itself (onto the pivoting holder)

"On the tensioner bearing the main surprise is that it is tight on the pivot assembly. A ½ socket extension used as a large punch and a couple of wacks with a hammer with the assembly held in the hand, and the old bearing was off. A long bolt and a couple of washers worked well to press the new bearing on the shaft at its hub. A little antifreeze dribbled during the operation. I still am fuzzy on what the heck antifreeze is doing dribbling out just because I took the nut off that secures the tensioner bearing. But it stopped when the new bearing got its final seating after the ½ rotation of the crank and re-tighten routine."