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Mechanical belt tensioner

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This is an explanation of how to install the mechnical belt tensioner, while the engine is still inside of the engine bay.

THIS ARTICLE DOES NOT EXPLAIN HOW TO INSTALL THE TIMING BELT, ONLY HOW TO INSTALL AND ADJUST THE MECHANICAL TENSIONER

The kit was purchased from parts dinosaur and includes the following: 150-teeth timing belt, mechanical tensioner, idler pulley. Now the necessary components have already been removed, just like the preparation of a timing belt change. You will no longer need your old hydraulic tensioner, and you can remove it with the bolts or bolt it back and leave it there. I opted to remove it from the engine entirely.

The rear timing belt cover needs to be modified like it shows on the parts dinosaur website, 420A Mechanical Conversion Kit Images


With the passenger motor mount removed, jack up the engine a couple of inches to provide easier clearance for your tools.

Remove the bracket that held the original hydraulic tensioner pulley; the new mechanical setup comes with a bracket attached to the pulley. (see 3rd and 4th picture.) Use the 2 original bolts from old bracket and torque down mechanical pulley to block. They are 12mm bolts, which I torqued down to 20 ft. lbs with lock thread paste. Another picture has been taken to show the cramped room in which you are working with.

The next picture shows a close up of the pulley, a quarter inch socket is used to tighten down the belt, which you will see later.

Go ahead and install the idler pulley as well, but do not tighten it down all the way. You need the pulley to be a little loose in order to give you the appropriate slack to install the timing belt.

Loosen the nut on the mechanical tensioner pulley (13mm), but DONT remove it, this will allow you to rotate that 1/4 inch square hole. Now, you want to rotate this hole clockwise, opposite direction of the arrow, until it will no longer rotate. This will loosen the pulley enough for the belt to slip on.

Line up all the appropriate markings, crank and cam gears, and install the timing belt starting from the crank going in a counter-clockwise direction (water pump, idler pulley,exhaust cam, intake came and lastly the mechanical pulley). Make sure you pull out all the slack because when you finally try to slide it on the mechanical pulley. Your going to have to tug a but to get it on. (This is why the idler pulley shouldn't be tightened all the way just yet.) Once the belt is on, it's now time for the tricky part.

1) Torque down the idler pulley, 15mm bolt torqued to 25 ft. lbs, now it's on to the mechanical pulley...

2) The picture shows the marks you are supposed to line up, if you look at the other pictures you will see how they don't line up originally. To line these marks up, you use the 1/4 inch ratchet to rotate the hole counter-clockwise, which tightens the pulley onto the belt.
That little tab right above the pulley moves clockwise towards the spring as you move the 1/4 inch hole counter-clockwise. Now I know this is hard to picture so I included a video which should give you an idea on how this works. (Parts dinosaurs has a little video of this as well).

Once these marks line up with one another your going to need to hold the ratchet in that position AND tighten down that 13mm nut on the pulley. (So keep a 13mm wrench nearby). The problem with this step is that you physically can't see these marks line up with one another. so you need to figure out a way to snake a mirror down there, or do what I did and use a camera.

(I had to aim the lens at the area and rely on the auto focus of the screen to help me out. I took a picture once it looked aligned to me, checked to make sure on the screen, set the camera aside, grabbed the 13mm ratchet, while holding the ratchet to keep the alignment, and snugged down the nut on the pulley. Sounds complicated, but it wasn't that bad.) This again is why you need to jack up the engine a few more inches.

3) Double check with the mirror or camera to make sure these marks are aligned and then go ahead and torque down that nut (22 ft. lbs +-2 ft. lbs). Rotate the crank 2 complete revolutions and then check all your timing marks to make sure they line up, if they do then your done.

If after the two revolutions they are off, then you must loosen the idler pulley, loosen the tensioner pulley nut, take off the belt and re-align these marks; then go through the process of lining up the tension pulley marks again (steps 1-3 listed above)... I had to do this 3 times because the timing marks were off. Tedious...

That is pretty much it....
 

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Here is the video I was referring to to help you understand the idea of the marks lining up on the pulley. Sorry it's so dark I forgot to shine the light (and ignore the radio)

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The little metal tab turns clockwise as you ratchet the 1/4 inch square hole counter-clockwise

It doesn't click or signal to you that it is lined up so you need to actually see it...
 
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