Tech Tip No. 18
Ned Ritchie
Originally published in the Northwest Region Quattro Club
Newsletter
Copyright 1998
Misleading Torque Values!
After spending all that money on your "Official Factory Repair
Manual" you'd expect the instructions, wiring diagrams, and torque values to be correct. I'm sure every effort has been made to ensure the highest degree of accuracy possible, but there are errors.
Here is an example: One repair manual specificies the clutch
cover bolts torque as 55 foot pounds. Enough to easily break them off when tightening. Use common sense.
If something doesn't seem right perhaps it isn't. How many would you break before you thought something was wrong? Don't just assume that it is correct. If in doubt call an expert. In this instance if you looked carefully on the same page with the pictures of the flywheel and the clutch parts you'd see that the flywheel bolt torque as 18 foot pounds which much less than the 55 foot pounds for the smaller bolts! What happened? The values were just switched!
Another example that could slip by you. The torque
specification for the crankshaft pulley center bolt is 350 Nm or 258 ft lb. Yup! That's about all you can pull any way and you probably weight even less.
What a few manuals forget to tell you, or tell you only in a
different place is that the 258 ft lbs is correct only when using an 18 inch long extension tool (VW/Audi tool Part # 2079) as an extension to your torque wrench!
If you just put on a large wrench and perhaps jumped on it thinking
you were somewhere around the 258 ft lbs specified you be way off. One shop I know of didn't get it tight enough and had to buy a head and valve job for the owner of the Audi.
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