Crank bolt torque for timing belt change (10v)

[JShadzi at aol.com]

You guys crack me up, for the last 10 years I've used the "1/2" breaker bar with 3 foot extension, get it as friggin' tight as I can, stand on the end of the bar" method.  

Curious to know if its 512 or 516 ft-lb  ;)

Javad

>> Date: Mon, 01 Dec 2003 08:16:20 -0500
>> From: Kneale Brownson <knotnook at traverse.com>
>> Subject: Re: Crank bolt torque for timing belt change (10v)
>> To: antar at comcast.net, quattro at audifans.com
>> Message-ID: <4.1.20031201081221.017add20 at pop.traverse.net>
>> Content-Type: text/plain; charset="us-ascii"
>> 
>> I thought a torque wrench applied a measured amount of torque TO THE
>> SQUARE
>> DRIVE PART of its assembly????
>> 
>> If you put a 258 ft. lb. torque setting on a torque wrench five feet
>> long
>> or one foot long and make it click, you've applied 258 ft. lb. of
>> torque to
>> the square drive fixture.  The Audi tool is designed so that when you
>> supply the desired torque to the hole in its end, you've applied the
>> correct torque to the nut on the crankshaft.
>> 
>I do not agree.
>For practical purposes it doesn't make enough difference to specify the 
>length of the torque wrench. Any torque wrench that is capable of 
>delivering that amount of torque would have to be of a certain length to 
>be manageable. However, the torque would vary dramatically if a 1 ft 
>wrench were used vs. a 5 ft wrench. Think of it like this:
>Assuming a 1ft long SST with 258ft-lb delivered at the end of the torque 
>wrench,  
>1ft torque wrench = 258lb on end X 2ft = 516ft-lb at bolt.
>4ft torque wrench = 64.5lb on end X 5ft = 322ft-lb at bolt.
>5ft torque wrench = 51.6lb on end X 6ft = 309.6ft-lb at bolt.
>So the final torque is dependent on the length of the torque wrench since 
>the SST is a constant. The longer the torque wrench is, the less 
>significant the SST becomes. It would also appear that error could be 
>introduced depending on where the torque wrench were held.
>  I personally use the cheater pipe on the breaker bar method.
>Mike
>
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