2G: Timing Belt Tensioning Question

[thach]

I've been reading a lot of sources about tensioning the belt and many of the methods differ - from different websites, different threads, the vfaq, and my haynes manual. I just need some clarity on this issue so I can finish my timing belt.

In the timing belt tensioning tips thread it is stated that its not necessary to measure the distance between the tensioner and tensioner arm with a drill bit - but i still have to compress the tensioner with the special bolt correct?

If the above answer is yes, does the grenade pin remain in or should it be removed? The vfaq says remove, but another source says to keep it in.

How much should the auto tensioner be compressed?

At this point, I believe I should torque the pulley down after using the special tool to apply 2 ft-lb to tension the belt.

Then proceed with rotating the crank, etc. and checking the gap.

If someone can clear up these few steps for me I'd appreciate it. Thanks.

[DSM1G90]

the people who wrote the info in VFAQ should know what they're doing since they're experienced professionals. Granted, they have picked up some shortcuts and tricks to help the beginner to novice DIY car owner.

Otherwise, they wouldn't be posting tech info in that site.

That should swing you in the right direction ..

When I did my belts in my 6bolt, I followed VFAQ all the way and have been very satified ... and still going strong 21k miles later..

-DSM

[luv2rallye]

If you compress the tensioner in a vise (very, very slowly) to put the holding pin in first before installing, you won't need the special battery hold down bolt (or tool MD998738 rod) for this. [The rod or battery hold down bolt is only used to compress an already installed tensioner so you can put the pin in (or pull pin out if needed)]. Now loosen tensioner pulley bolt, install tensioner (with holding pin in), and then put the timing belt on. Then use 90 degree pliers or allen wrench (or special tool MD998767) to move the tensioner pulley against the timing belt (so belt gets tightened) until the holding pin slides easily in it's hole. Then tighten tensioner pulley and remove holding pin. Then rotate crank 6 times, wait 15 minutes for belt to stretch, and redo tensioner pulley adjustment so pin can again slide easily in/out hole (but don't leave pin in when done). When pin slides easily through the hole you have the correct adjustment for timing belt tension.

All this is explained here: Timing belt tensioning tips (for 4g63 turbo)

[DSM1G90]

Yep, that sounds so much easier to do. ... just like the trick, listed in VFAQ, in doing the oil pump balance shaft - in getting it in phase without doing the bolt removal thing...

[zanderson]

This video should be helpful.
New Timing Belt Tutorial Video!

[thach]

luv2rallye, thanks, that was a lot of help. And the updated thread is great. How slow is slowly when compressing the tensioner? Mine is already out so I'll go that route.

[snowborder714]

When I compress mine in a bench vice, I'll do it 1/4 - 1/2 turn of the vice handle at a time very slowly (maybe about 5 seconds per 1/4 turn). Then I'll wait 20 seconds in between each turn. It'll take you a while to do.

[thach]

Sounds like beer will be good for this. Cool, thanks!

[DSM1G90]

Good video but it ain't fair since his block was on the stand where the most of us are doing this while under the hood..

On the tensioner pulley: I put a socket (nice to have a 1/4" drive on that socket since you don't have the room...) on the bolt end of the pulley, then take an allen wrench and place it in the left hole of the pulley so I can use that socket as a fulcrum for the allen wrench (the wrench lays over the socket) to aid in rotating that pulley when I push on the end of the wrench to get my correct tension. And when I do get the clearance is when I sinch down the bolt and do my rotation to see if the clearance settled down, or needs more adjusting.

ya, that's pretty big to remember that front balance sprocket plate (I wish it was configured with balance shafts to be more thorough of a video so you can see how to time both sprockets, esp the oil pump sprocket...), for I've seen belts snarled up when it's on backwards..but the timing mark really doesn't change either way.

-DSM

[thach]

Yeah I had my plate on the opposite way but i was able to catch the mistake.

[illusivEnt]

You don't have to be that slow just make sure you are steady turning it and if you need something to put in the hole to hold it down a little drill bit works great. I just did mine about a month ago.

[RedVengeAPX]

Hey man if you need help with this I'm just 15 minutes away from buffalo and I have the Jay Racing timing belt kit with all the tools it only takes a few minutes. I've done the process many times, just pm me if you need a hand.

[DSM1G90]

To add to the video: his setup doesn't have that plate installed to where in reality, that plate acts like the inner flange of the crank sprocket to keep the belt centered on the sprocket (the harmonic balancer pulley is the outer flange for that sprocket and to protect the belt from creeping into that BS sprocket and snarling up the inboard edge of the belt) being it's the powered sprocket whereas the oil pump sprocket is a roller type sprocket and can't really hold the belt to center.

So it's best to those who do BS removals: keep that plate and in correct direction against the BS sprocket to help the main belt to stay center on the main sprocket.

-Good luck, all - DSM

[thach]

^ good info to know.

I went pretty slowly compressing the tensioner, 5 s 1/4 turns, ~20 s intervals. Really doesn't take that long.

Originally Posted by DSM1G90

On the tensioner pulley: I put a socket (nice to have a 1/4" drive on that socket since you don't have the room...) on the bolt end of the pulley, then take an allen wrench and place it in the left hole of the pulley so I can use that socket as a fulcrum for the allen wrench (the wrench lays over the socket)

Also for this, I'm assuming you have a 1g, with which you tension the pulley clockwise. For a 2g you have the do it counterclockwise, so reverse the allen key process. Just fyi for others.

[thach]

Hey peeps, just tensioned my belt tonight. After rotating it six times and waiting 15, the pin slides in and out easily. However, after i torqued the pulley down to spec (it was tightened just to keep the pulley from moving before), the pushrod in the tensione is extended and the pin can no longer slide completely through. Is it supposed to be this way or have I done something wrong?

Also i have about 1/4 in deflection in my belt between the cam sprockets.

EDIT: that question was pretty noobish of me...I think the answer is that it's wrong? the pushrod extends too much I believe, although I didn't measure it. so I gotta redo it, right?

[luv2rallye]

Did you rotate it a few more times after the wait period was over before rechecking? The TB will normally get slightly tighter and looser as it's rotating depending on cams position (force from holding different valves open). Try to do the adjustment when it's looser.

Adjusting the final (torqued) tensioner pulley position so that the auto tensioner holding pin moves freely all the way through the auto tensioner body and pin holes is the ideal target. Adjusting the tensioner pulley to do this will automatically make the distance between the tensioner arm and auto tensioner body be about .157 in. Since the spec for this is .150 - .177 in. this works. But anywhere in that range is ok (can use drill bit to measure) since the TB tightens and loosens slightly with rotation.

1/4" deflection is ok.

[snowborder714]

When I do this, I get the bolt finger tight just when the pin starts to move. Then I tighten down the bolt with a wrench, keeping in mind that the pulley will move in the direction that the bolt is being turned. Because I started with it not at the perfect spot, but a bit before it, after I tighten it down the pin ends up being just where I want it and able to move freely.

Or if you're a little more advanced and have the tensioner pulley tool, you can counter the pulley movement with the wrench that has the tool on it. A bit hard to explain, but you'll be turning the wrench/tool the opposite direction of the wrench that's tightening the bolt.

[steve]

Originally Posted by luv2rallye

Did you rotate it a few more times after the wait period was over before rechecking?

The point of checking after the wait is to make sure that the tension hasn't changed out of spec in that period of time. If it has then it's wrong or the auto-tensioner is dead. If you turn the crank again you have to wait again before checking.

[kamikazi]

Originally Posted by luv2rallye

If you compress the tensioner in a vise (very, very slowly) to put the holding pin in first before installing, you won't need the special battery hold down bolt (or tool MD998738 rod) for this. [The rod or battery hold down bolt is only used to compress an already installed tensioner so you can put the pin in (or pull pin out if needed)]. Now loosen tensioner pulley bolt, install tensioner (with holding pin in), and then put the timing belt on. Then use 90 degree pliers or allen wrench (or special tool MD998767) to move the tensioner pulley against the timing belt (so belt gets tightened) until the holding pin slides easily in it's hole. Then tighten tensioner pulley and remove holding pin. Then rotate crank 6 times, wait 15 minutes for belt to stretch, and redo tensioner pulley adjustment so pin can again slide easily in/out hole (but don't leave pin in when done). When pin slides easily through the hole you have the correct adjustment for timing belt tension.

All this is explained here: Timing belt tensioning tips (for 4g63 turbo)

i have done the vise as well it works just as good as anything but do it very slowly as doing it too fast could cause it to explode and its not pretty

[thach]

Hey guys, finally found some time to work on the car tonight. I think all is well now.

I went through the tensioning process, waited 15, then retensioned and the pin slides in and out like butter. Thanks for all the help and advice!

[steve]

Originally Posted by thach

I went through the tensioning process, waited 15, then retensioned and the pin slides in and out like butter. Thanks for all the help and advice!

If you retension the belt you have to then wait another 15 mins before checking the pin.