Any tricks to getting the timing belt back on?

[wohpony]

Ok so I pulled an idler pully thinking the timing belt would stay put. Needless to say it popped right off and now im trying to get it back on the less painful way possible. any help would be great. ( trying to do it with out disasembly)

[Inodoro Pereyra]

Sorry, not gonna happen.
You need to take the timing cover and the hydraulic belt tensioner off (just the cylinder, not the pulley assembly). Then, with a vise or big C-clamp, you need to compress the belt tensioner until the hole in the plunger lines up with the 2 holes in the lip of the cylinder (if it takes you less than 20 minutes to do so, replace it), and put something (a nail, or a thin drill bit) across the 3 holes. Then, put the belt back on, the idler pulley, and finally the tensioner, and pull the pin.

[Ryan]

What do you mean by less than 20 mins, Inodoro? Isn't the time it takes inversely proportional to the ammount of force you use?

I realize you should do it slowly... but I could make a good or a bad tensioner take 20 mins.

[Inodoro Pereyra]

When you push a little (let's say, 1/4 turn, if you're lucky), it gets to a point where the tensioner won't let you go any further. Then you have to stop for a moment, until the pressure of the fluid goes down and you can push a little more.
I had to do this several times, with the tensioner I had rebuilt (that normally took me about 15-20 minutes), which ultimately didn't work, and a new one, that took me 35-40 minutes to compress. So I take about 20 minutes as the shortest acceptable time for a good tensioner.

[davmac]

20 minutes to compress the hydraulic tensioner? Sorry but I find this to be bizarre advice. Maybe using a large c clamp it will take you a long time. If you have a large enough vise or a press and you take your time this should take 20 seconds. You just don’t want to push the piston off center.

[Inodoro Pereyra]

Really?

Davmac: how many times have you done it? I could bet you money that if you try to do that, you will crack the tensioner's aluminum body long before you can compress it.
That is, of course, if the tensioner is in good shape. If it's shot, you can compress it in 20 seconds just using your hands...

[davmac]

Inodoro - I completely respect your advice here and have no disagreement with the response to the OP. The OP will be replacing or re-installing the timing belt and will need to remove and compress the tensioner. I just don't see how 20 minutes became the standard time it should take to compress a good tensioner. I’ve done this 2x on my MX3 and once on a Toyota V6 with similar style hydraulic tensioner. With sufficient leverage using a vise or a press it doesn’t take 20 minutes to compress. Maybe I exaggerated slightly and it took 1 - 2 minutes. These were new or nearly new tensioners.
I suspect the OP may have other questions about replacing or re-installing the timing belt. It can be a bit tricky but the service manual through this site gives good step by step directions. So back to the topic …

[Ryan]

Again, it depends how you're compressing it.

I use my bench vice, and I apply just enough pressure the move the cylinder, and try to hold that force, and it rebounds/bounces a little as it compresses. I wouldn't say it takes me more than a few minutes either.

If you're using a baby c clamp with a 1" arm, sure, 20 mins.

[Inodoro Pereyra]

Ok, I never said 20 minutes was "THE" standard for compressing the tensioner. I said it's "MY" standard.
I used a 6" C-Clamp to do the job, and, because I'm an idiot (I was using the wrong timing marks), I had to do it more than a dozen times, first with the unit I had rebuilt, and finally with a new one.
In all cases, I compressed the cylinder until I couldn't go any further (and, believe me, I have broken 2 vises in the past, so I'm not what you call a weak guy), and then waited for a minute or so for the pressure to go down. Of course I could've put the C-clamp on my vise (it's a 4 inch, so it's not big enough to do the job directly) and use a lever to apply more pressure, but, as I said, I was worried about the aluminum body cracking under the pressure of the fluid.

So, that's the time it took ME to do the job, and, based on that, that's the time I use to determine if a tensioner is good or bad, being that the rebuilt unit still let the timing belt flap around when installed.

[projectzemx3]

lol no you wanna know the best trick for these timing belts???


after you get that tensioner depressed where it bolts too the block, take out the bottom tensioner bolt and losen the top one (the top one doubles as a waterpump hold down)

removing the bottom bolt will allow the tensioner to pivot and get that pully even farther away from the belt, slip the belt on and then move the tensioner ack into place and put that bottom bolt back in.

doing that will help sooooo much, trust me ive timed a KL many times.

also another little tip is when you line your cam pullies up, line the front one up perfecty, and the rear bank has two marks about a half inch apart, move the pully slighltly forward (clockwise) so the marks actually aernt lined up, it should look slightly advanced.

this way when your tensioner is released you will notice your rear bank will be perfectly lined up, all 4 points. putting tension on the belt will cause that rear pully to move backwards, if you line the points up then release your rear bank could very possibly be one tooth out.

[projectzemx3]

Really?

Davmac: how many times have you done it? I could bet you money that if you try to do that, you will crack the tensioner's aluminum body long before you can compress it.
That is, of course, if the tensioner is in good shape. If it's shot, you can compress it in 20 seconds just using your hands...

ive compressed these tensioners a dozen or so times, i use a large vise, it takes less then a minute to do with no problems whatsover.

infact one time i wedged it under neath the frame of my mx3 and used a flloor jack and put the tensioner inbetween, jacked it up and put a cotter pin through it. lol even that didnt take 20 minutes.

[Inodoro Pereyra]

Oh, boy...

For the second (and hopefully LAST) time, that's the way I do it. I base my advise on the way I do things.
So you can compress the tensioner with your car? Kudos to you. I rather spend half an hour compressing my tensioner, and then install it knowing it's in good shape, than do it in a minute, and then have to spend hours disassembling the timing again because either the tensioner was bad in the first place, or I screwed it by compressing it under such weight.

But to each their own. If you think compressing it under your car is the right way to do it, the more power to you. Like I said, I don't think that's smart, and I don't think it's worth the time savings.

[projectzemx3]

lol you must not work flat rate then

[Inodoro Pereyra]

Nope, never. I've seen how mechanics that work at a flat rate make the money. I'm an honest guy.

[94mx3precidia]

this is how i did it.

I alligned both cams. the crank gear, i turned it one tooth ccw so that when the tensioner sprung it would pull the tiny bit of slack you cant get out of the front cam side out and then all gears would be aligned.

or

the second time i did this i aligned all cams including the crank. took as much slkack as i could get to the front cam. once i have all the slack there i would install the top tensioner pulley as i pushed down on the pulley making sure it would not crossthread.

just rember when you check your timing once you think you have it turn the crank --> 4 <--- times to make sure.