Timing belt tensioner pulley does not "pivot nice & freely"

After a few hurdles, I'm reassembling after a timing belt change and then having to disassemble again due to multiple issues. In another thread, I worked through the timing belt tensioner pulley hole being stripped and repairing by installing a heli coil.

In the three-part video by 1A Auto in the timing belt sticky thread, he reinstalls the timing belt tensioner pulley which uses an Allen bolt/wrench. When done in the 2nd video at 9:57 he tests to be sure the tensioner pivots freely. You can see it pivots without resistance

Mine does not at all.

And yes, I put the spacer on. I was beginning to torque it down but have yet to torque it down fully. And it pivoted very freely before installation

I even put a very light amount of grease between the spacer and the part of the pulley that should pivot

Thoughts and suggestions greatly appreciated

I believe it is supposed to be torqued to 34 foot pounds. I am at 19

 

Something is wrong then. Is it missing a bolt sleeve or something? You shouldn't be tightening on the actual tensioner.

 

I even got a brand new bolt and spacer.

I am tightening the part that connects to the Engine that uses an Allen bolt just like in the video. The tensioner pulley comes preassembled




from the video

 

Should there be another spacer on the outside as well?

you can see in the pictures in the previous post where I still have the Allen wrench inserted

 

Is it possible that that hole is a very specific depth so that when you're torquing it bottoms out?

when installing the heli coil, we approximated the depth, but there's no way to get it precise


I also added a screenshot in the video where he is testing that the pulley moves freely. It does not appear that there is another spacer

 

Is there a sleeve in that allen head bolt hole?

 

It appears that the allen head bolt and washer combo (no sleeve) should not allow the tensioner to get overly tightened. Do you have the old tensioner to compare it to?

 

yes, it comes with one. And I even bought a new bolt but both react the same.

here's a picture of the old one

 

Something must be out of spec then. Bolt too short, or bracket too wide perhaps. Maybe the washer is the wrong thickness. Weird.

 

Here they are side-by-side. Not sure why I thought I had to take the pulley off of the old one.

I looked closely and I can see no difference

and I tried the new tensioner pulley with the old bolt and spacer and a new bolt and spacer. Same result.

 

Not the washer / spacer I've tried an old and a new washer / spacer (edit: and now the old bracket, bolt, and spacer with same result).

The only thing I know to do is to transfer the new pulley to the old whatchamacallit. There's nothing on the old that should be worn out. The pulley and pulley bearings would be new if I do transfer it to the old one

Visually, I cannot see a difference in size, but the design does appear that the sleeve of the bolt should keep the tensioner unit from pressing up against the spacer and engine too tightly. The end of that bolt/sleeve should be what is pressing against the spacer and engine which should allow it to pivot freely

 

Is this the pulley that changed the wheel size from the older component to the newer updated one?

 

I believe that is on the serpentine belt tensioner at least I think

it is not the actual pulley that is causing the problem

I wish I had a micrometer to measure the difference in the units

 

I just tried the old bolt with the old tensioner and got the same result

so not out of spec

The only thing that changed is installing the heli coil

I checked the mating surface and there is no damage from installing the heli coil there either

 

Is this the heli-coil hole?

 

Yes

and there really is no way to check to be sure it is at a perfect 90° Because of the design of that bolt.

I suppose I could get another bolt that is the same size, but it would be very hard because the head Would make it hard to Measure

edit: duh - get a stud the size of that bolt

 

This is gonna require a more custom solution then

 

Without the tensioner, just installing the bolt and washer, how does it look? Tilted off axis? Does it look like the washer isn't sitting flat, but is being pressed up on one side?

 

Does not appear to be. I had an extremely experienced industrial mechanic install the heli coil and I assisted, and he was very careful to get it as exact as he could without removing the engine


Visually it looks OK, and also from pictures. The slightest difference in camera angle could make it appear different but here are two pictures, one from the top and one from the side.

from the top:


From the side:

 

This gap is concerning in this angle. Is it consistent all the way around?

 

It looks to me like it is. I feel like the gap is the same on the top.

I guess the only way to check for sure is to get a feeler gauge

but not sure you could get one that thin now that I think about it

 

The only other option would be to get something to measure from the base of the engine to the flange (?) of the bolt on each side

 

It's hard to see you from the passenger side, but to me the gap looks the same at the top and on that side

The camera angle can certainly have an impact

 

I'm thinking based on the symptoms that the washer face and bolt flange are compressing the pulley bracket as you torque it. The original tolerance is pretty snug to keep it from rattling on the bolt, but leaves enough space to allow free rotation.

 

That definitely has to be what is happening.

And what else could be causing that with the old and the new bracket as well as the old and new bolt other than the slightest micro imperfection in the angle?

It normally pivots extremely freely and this gets very tight long before you come close to getting it torqued correctly


I say long before, but it is 15 foot pounds shy. At 19 ft/lbs it is extremely snug and it should be pivoting freely at 34 ft/lbs

 

The design seems to be that the only way it could compress and be torqued is if this part of the bolt compresses against the spacer and the bracket is ever so slightly shorter than the sleeve on the bolt in order for it to pivot freely

 

Exactly

 

I wonder if a drill guide could be used to confirm

 

Somehow, I've got to confirm

After that, I guess if The new hole is ever so slightly off my options would be:

1. mill the bracket down ever so slightly, just enough to create enough space for the bolt sleeve to engage the spacer and there by allowing the pulley and bracket to pivot freely Assuming it is an extremely minimal difference from 90° on the bolt hole
2. Install a big sert (a time sert designed for when you've already drilled out one time as was done for the heli coil). I believe it has an optional guide to ensure it is installed at a 90° angle
3. Replace the oil pump

 

Man, late to the party, been working on the truck all morning. @KNABORES is on point as usual.

In all seriousness. I'm not trying to cause you more work or anything, but this is going to bug the living fuck out of you unless you replace that oil pump, I suspect. I say that before having looked up what labor is involved and if you can even comfortably do it w/o pulling the block, or even looked up the part cost for that matter. I seem to recall a fair amount of work watching the teardown videos in the 2nd reply of the megathread, but he already had the block out.

Now, I also realize, if you install the new oil pump and encounter this same shit, you're gonna be kicking yourself