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Have you ever seen this on a cam gear sprocket?

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Old 04-07-2017, 01:30 PM
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syoo8
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Default Have you ever seen this on a cam gear sprocket?

Hi everyone,

I'm trying to button up my TB/WP install on my '87 S4. It has a Porkensioner.

A couple of observations:

1) This dropped out as I removed the Porkensioner pulley.

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Anyone know what it is?

2) The Porkensioner pulley did not swivel after I removed the old Audi tensioner. I thought, "that's odd, isn't this thing supposed to swivel?" Then I read old threads, including one by Rob Edwards, noting that there needed to be two washers, one in front, and one behind, the pulley. Well, the previous owner only installed one washer.

3) I thought that two washers would do the trick but it did not. It turns out that the metal dowel that goes through the center of the pulley (which allows the pulley to pivot) was caked with dirt and bound. After cleaning it it was much better.

4) Most important: I used Porken's 32V'r tool to adjust the valve timing. The passenger side was reading 7 degrees of retard. So I used my Porken Bumpstick and adjusted the timing back to 0. Then I spun the crank 720 degrees until back to 0|T, and, voila, it was still reading 7 degrees of retard!

I thought maybe I was doing something wrong-- and then I saw this:

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Anybody know what that plate of metal is that has the "L" and the "R" written on it? Is this the reason I cannot adjust the timing?

Thank you all in advance!
Old 04-07-2017, 01:55 PM
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PorKen
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1. Timing belt cover spacer (non-airpump type)

2. Ugh

3. You may want to replace that pulley

4. You are probably max'ed out in the cam gear slots and/or one tooth off. You probably need to restring the belt and may need to re-center the cam gear(s)


That is the hall sensor rotor (for ignition timing). Speaking of which, considering the state of that engine, I would check the if the hall sensor is in good condition and plugged in.
Old 04-07-2017, 02:03 PM
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FredR
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The thing with L and R on it is part of the Hall Trigger kit.

Are you sure you are locking the cam up correctly after the adjustment? If you are using the bump stick kit and can read the adjusted timing then I would think you are not locking it in position correctly.

I trust you tightened the three small allen bolts to lock the cam in position after the adjustment?
Old 04-07-2017, 02:09 PM
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syoo8
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Hi Fred-- thank you for your reply!

I believe I am following the instructions meticulously with the bumpstick-- it has worked for me in the past?

Yes I am tightening the three 4mm allen bolts after adjustment.

Could you explain what this hall trigger kit does?
Old 04-07-2017, 02:32 PM
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syoo8
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Originally Posted by PorKen
4. You are probably max'ed out in the cam gear slots and/or one tooth off. You probably need to restring the belt and may need to re-center the cam gear(s)
Ken, thank you very much for your reply!

When I restring the belt, do I need to remove the tensioner to do so?
Old 04-07-2017, 02:51 PM
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FredR
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Originally Posted by syoo8
Hi Fred-- thank you for your reply!

I believe I am following the instructions meticulously with the bumpstick-- it has worked for me in the past?

Yes I am tightening the three 4mm allen bolts after adjustment.

Could you explain what this hall trigger kit does?
Scott,

The Hall trigger is used in conjunction with the crank position sensor and the knock sensors to monitor what is going on and when in the engine. Thus the system in the S4 and later models can detect any cylinder that is knocking and thus apply a correction retarding the timing on that specific cylinder up to 9 degrees until the knock stops and thus protect the motor from say poor gasoline. If the system detects a fault in either the Hall trigger or the knock sensors an across the board retardation of 6 degrees is applied to all cylinders and that makes a huge difference to performance.

Regarding your cam timing- if you remove the spacer and lock up the cams where abouts do the threaded holes sit relative to the slots in the cam sprocket? They should sit about half way across the slot.

I fail to see how you can measure the timing to be at zero on the 32VR and then two revs later find it a minus 7. On the other hand if you have not locked the sprocket correctly, when you turn the engine the sprocket will slip until the screw is at the end of possible travel thus retarding the cam. As I seem to remember the slot permits about 15 degrees of advance/retard and if it slips from the middle to the end of travel it will retard about 7 degrees or so.
Old 04-08-2017, 08:38 AM
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ammonman
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After making your adjustments are you removing the spacer from underneath the cam bolt and torquing the cam bolt correctly before spinning the engine?

Mike
Old 04-08-2017, 11:04 AM
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Originally Posted by ammonman
After making your adjustments are you removing the spacer from underneath the cam bolt and torquing the cam bolt correctly before spinning the engine?

Mike
Hi Mike.

NO. I didn't do this-- and I realized that I needed to remove the porken spacer before spinning the engine... I'm not stupid, but sometimes I am really dumb!

Thanks for writing this-- perhaps others will learn from this thread!
Old 04-08-2017, 11:33 AM
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If all else fails read the instructions!

The only people who do not make mistakes are the ones who do not do anything. Finished my work the other day, took the car off the axle stands and took it for a test drive. Driving along the avenue away from my house and a strange noise. Turned it around gingerly, back to my home about 400m away and tightened up the wheels.

Last edited by FredR; 04-08-2017 at 12:12 PM.
Old 04-08-2017, 11:44 AM
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Bertrand Daoust
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The only people who do not make mistakes are the ones who do not do anything...

+1.

I think everybody here would have a story to tell...

Like me when I did my intake and valve covers refresh and put the fuel regulator at the front damper's place. The car wasn't starting and I was wondering why!

Keep up the good work Scott.



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