Resolved 1G Mysteriously reapprearing timing belt slack

[Noranuzoki]

I've been having issues with slack in the top of my timing belt. All parts are new (greddy blue timing belt, pulleys, auto tensioner, aem adjustable cam gears, etc). I don't think this has anything to do with it but I thought I'd note. The balance shafts have been deleted.

I've been using a drill bit that is in-between the auto tensioner spec to make sure everything is in absolute spec. It doesn't come back instantly and it's not an issue with correct timing. Just a matter of slack in-between my cam gears. When I go to retime the car it seems like the eccentric pulley has rotated counter clock wise. So I know it's loosening but I have no idea why. Note: I have been torqueing the pulley according to spec (33ft-lbs).

I've been thinking about putting blue lock tight or a lock washer on that pulley but I'm not sure if that is such a smart idea. So I wanted to get opinions on it before I just "band-aided" it.

Here's a diagram of what I'm talking about, I don't have pictures of the exact issue yet:

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[dwb]

Some slack between the cam gears is normal depending on the position of the cams.
Is it an OEM tensioner? Are you rotating the crank at least 6 times clockwise when setting tension?
Does the bolt on the eccentric pulley feel loose when you go to re-tension it?
Is it possible your torque wrench is out of calibration?

 

[pauleyman]

This is normal. As long as the tensioner protrusion is in spec you should ignore this. Its been a long discussed topic for as long as DSMs have been around.

 

[Noranuzoki]

This is normal. As long as the tensioner protrusion is in spec you should ignore this. Its been a long discussed topic for as long as DSMs have been around.

Are you sure? The last time I ignored it, I had to rebuild my head. Though I'm pretty sure I didn't do it correctly the last time. Either way, still a little bit scary to see.

I'll send a video of it when I get home.

Some slack between the cam gears is normal depending on the position of the cams.
Is it an OEM tensioner? Are you rotating the crank at least 6 times clockwise when setting tension?
Does the bolt on the eccentric pulley feel loose when you go to re-tension it?
Is it possible your torque wrench is out of calibration?

Yes, I'm using the OEM Auto tensioner. I rotated the motor 2 complete cycles when setting tension according to 90 service manual.

 

[pauleyman]

Are you sure? The last time I ignored it, I had to rebuild my head. Though I'm pretty sure I didn't do it correctly the last time. Either way, still a little bit scary to see.

I'll send a video of it when I get home.


Yes, I'm using the OEM Auto tensioner. I rotated the motor 2 complete cycles when setting tension according to 90 service manual.

All that matters is the hydraulic spec. If its right you're done. Ive done 100 or more timing belts. Don't overthink this.

 

[chrysler kid]

The slack is normal, after a period of time.

The intake cam likes to over rotate. It’s typical after a night of sitting the belt will have a little slack but it’s not enough to slip off of the cam gear. If the slack feels loose enough that it could jump timing then you haven’t set hydraulic tension correctly

 

[Noranuzoki]

All that matters is the hydraulic spec. If its right you're done. Ive done 100 or more timing belts. Don't overthink this.

You were indeed right sir! I was just weary about it. Its in spec and looking great. Thanks for reassuring me

Im going to get rid of this thread in 24 hours or someone can.

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[1990TSIAWDTALON]

Seven years ago, I had the same question. It was fine, the guys were right about the cams settle and make it appear to be "slack".
I actually think we should leave this thread up for anyone to see
Pops

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