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Discussion Starter · #1 ·
In a couple timing belt threads, there were a couple of us that noticed that our belt tension wasn't as tight as it was supposed to be set to as per the service manual (assuming things hadn't stretched, but I've peeked at the tensioner after a couple thousand miles and it hadn't moved/stretched, not even sure the belt can stretch). The service manual says to set the pointer to the hole. Mine was at the slot before I changed it (lower tension). See pic below...

Why do I care? There were also some posts about timing belt squeaks at hot idle, and a dealer reported needing to lower the tension to get it to go away. I've noticed that the tension goes up as the car warms up. Are many/most other cars tensioned a bit low from the factory? Is it reasonable to back off the tension like this to address the squeak?

I'm guessing not many people have looked at this before changing the belt, so I'm wondering if people would be so kind as to snap a picture before changing the belt for some addiional data points...

Mine before changing (originally set at the factory):
Wheel Tire Automotive tire Crankset Motor vehicle
 

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Here's mine. Pretty sure the pointer stays wherever the bolt gets torqued . . . so the Alfa factory was setting these with less tension than specified by the FSM.

Gear Automotive tire Auto part Bicycle part Automotive wheel system
 

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Cam lock tools were in. This is just prior to taking anything apart. Is there any further consensus on where we should be setting the pointer? I plan to use the FSM method unless there is a consensus for something different.
 

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Discussion Starter · #5 · (Edited)
Thanks, this is helpful. I don't know of a consensus, but I can tell you what I've seen after troubleshooting my own issue (squeak/howl/rattle at hot idle) after replacing it. After taking it apart, the sound was definately coming from the tensioner (used a stethescope to nail down). Figuring it was a bad tensioner (OEM brand), replaced it with another one, this time an SKF brand. Same thing at hot idle. Both done as per the service manual, tensioned to the hole (I'm a stickler for following instructions).

So, I did a search and ran across this:
Same sound as mine. The dealership ended up loosening the belt to fix it in that person's case.

I looked through my removal pictures (above), and noticed that mine was set a bit looser from the factory (I'm assuming the belt doesn't stretch much, I didn't notice any movement after a couple thousand miles)

Someone else also noticed theirs was a bit looser from the factory here:

Last week I received a picture from another forum member, and theirs was a bit looser like the others. Now I'm scratching my head. Are they all set that way, and is that why some have a squeak/howl when tensined as per the service manual? I went through the effort and loosed mine back to where it was from OEM (still plenty tight). Third try. I idled it for a half hour or so, up to operating temp, and didn't hear it. The real test would be to go out for a drive, but too cold here, will have to wait for spring. As an aside, the tensioner pointer moves a ton when it warms up. When running cold, it points roughly where it was set to. When hot, it really tightens up (for example, if you have it set to the slot like above, it will be well above the hole at hot). Is this why only at hot idle?

Now a counterpoint. I talked to Alfaworks, who I respect and trust, and they have likely done more than anyone. They tension to the hole, and haven't had any complaints. I sure can't argue with that.

Is it just some cars that have the issue? Not sure. It does seem that some are sensitive to too much tension...
 

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As an aside, the tensioner pointer moves a ton when it warms up.
OK, starting to understand this better.

I noticed that the FSM over-tensioning part (which Alfaworks' instructions skip) is to "settle the toothed timing drive belt." If you look at the surface of the teeth, you'll see that they're a soft, textured rubber so it makes sense that a couple of rotations will "settle" the belt into the gears. The end result is that you will have more overall tension on the belt with the "settling" step. Doubly so if you do this work over the winter in an unheated garage (since belt material expansion apparently forces the belt away from the gears and causes additional tension as you noted).

You've pointed out several examples of the FSM process resulting in an over-tensioned belt.

OTOH, Jamie's process, in addition to being more efficient by skipping the over-tensioning step, apparently has a low incident of "bring-backs." He runs a business for profit, so he should know.

I think I'll follow Jamie's procedure and skip the over-tension step.

Sucks that this is subjective. Wonder why this is so easy to do on Mazdas? Mazda timing belts don't have textured teeth either. Hmmmm . . . .
 

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Getting ready to put this back together this coming weekend (waiting for a couple of gaskets).

Here's a list of torque specs LABORIOUSLY gathered from the FSM. It's a hunt to find these. Jamie, if you're listening, you should add these into your procedure in one, easy-to-find place.

Accessory Belt Idler (M8) 26Nm
Accessory Belt Tensioner (M10) 50Nm
Alternator Bolts 25Nm
Camshaft Pulley Bolts 60Nm + 25deg
Camshaft Pulley Covers 30Nm
Engine Mount to Block (M10) 50Nm
Engine Mount to Block (M8) 26Nm
Engine Mount to Frame Bolts 75Nm
Engine Mount Lock Nuts 11Nm
Reaction Rod Nut 50Nm
Timing Belt Idler (M10) 50Nm
Timing Belt Tensioner (M8) 26Nm
Intake Cam Cover Bolts (M6) 9Nm
Vacuum Pump Bolts (M6) 9Nm
Water Pump Bolts (M8) 26Nm
 

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it could be that problem lies not in over tensioning but rather in one of components installed. best to mention makers of components installed. even OEM parts will have some markings of makers they were made by.

for example Conti/Continental aux belts tend to squeak, Dayco/Gates belts on same model don't.

PS same engine on 159/Brera uses tensioning to hole. never heard any noise
 

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Discussion Starter · #11 ·
it could be that problem lies not in over tensioning but rather in one of components installed. best to mention makers of components installed. even OEM parts will have some markings of makers they were made by.

for example Conti/Continental aux belts tend to squeak, Dayco/Gates belts on same model don't.

PS same engine on 159/Brera uses tensioning to hole. never heard any noise
I looked, and the OEM timing tensioner bearings were GMB, the one I have in there is SKF...
 

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Discussion Starter · #12 ·
A quick update. Over the winter, I backed down the tension to where it indicated originally (from before I had removed the original belt.) I've now put a few hundred miles on this setup. The squeak issue is MUCH diminished, pretty much back to normal and how it was from the factory...
 
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