Crank bolt torque for timing belt change (10v)

[Ameer Antar]

I'm not sure why I bother, but shouldn't the torque actually be a lot more than that? If you use the tool and you're putting 258 ft-lbs on the t-wrench, then for simplifiying the numbers you can assume the t-wrench is exactly 1-foot and you're putting 258 lbs at the end of it. (You could make the t-wrench 30 inches, but it's the same thing, you just need a different weight to match the 158 ft-lbs). So then you are also adding another foot of extension, so the new torque should be something like 258 lbs * 2 ft = 516 ft-lbs. Torque is simply the weight applied to the bar or wrench times the distance from the bolt center to the point where you apply the weight. I doubt you'd need to torque it that high to be safe, but it seems like that's what Audi wanted you to do. 

-Ameer

---Original Message---
Date: Sun, 30 Nov 2003 12:17:51 -0800
From: "KUNZ,BOB (HP-Boise,ex1)" <bob.kunz at hp.com>
Subject: Crank bolt torque for timing belt change (10v)
To: "'quattro at www.audifans.com'" <quattro at www.audifans.com>
Message-ID:
	<345D43ADFFFF864298F9ECD6C5D574E803136236 at xboi21.boise.itc.hp.com>
Content-Type: text/plain

OK, guys. I've looked for the actual torque on this bolt and have found so
far...

 

330 ft-lbs at the bolt

450 ft-lbs at the bolt

400 ft-lbs at the bolt

258 ft-lbs at the end of the 2079 tool

 

Of course Bentley says use the 2079 tool but they don't say how long the
torque wrench is which is a variable one must know in order to get the
setting right.

 

The center to center length of the 2079 is 12 inches. If the length of the
torque wrench is "L" and the torque setting on the wrench is "T" then the
torque delivered to the end of the 2079 tool is: T * ((12+L)/L). This
assumes the 2079 and torque wrench are in line, otherwise we have to apply a
sin function. So I'm missing one more variable, either the actual torque I
need or the length of the torque wrench that Bentley describes. Picture
17-223 in the Bentley shows that clearly the torque wrench is longer than
the 2079 but then the bar goes outside the picture frame.

 

So, anybody have the actual torque for this bolt?

 

--bob

 

'86 5ks Avant original owner

'02 TTQR



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