Date: Thu, 14 Jun 2012 09:41:51 -0500
Reply-To: JRodgers <jrodgers113@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: JRodgers <jrodgers113@GMAIL.COM>
Subject: Re: warning regarding GoWesty alternator bracket kit
In-Reply-To: <AD8DA70B-B55F-4586-88E3-2294010E2CE2@shaw.ca>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
So Bentley does in fact have a specified torque value for the bolt in
question. But that is for a factory supplied bolt. When bolts come from
other sources they are always suspect until properly identified by the
marks on the bolt head and cross referenced to a book of standard torque
values for the particular bolt in question. Even then, unless you know
the source, you may be getting cheap bolts made in 3rd world countries
where alloy composition is of no consequence - only the money from
sales. (almost sounds like the USA these days)
Back in my aviation heyday every nut, bolt, washer, rivet, what have you
had to have source records or it didn't get used. That way if an engine
fell off - failed parts could be traced to their source and the problem
fixed, whether bad alloy or crappy mechanic work. Would not want to
blame a parts manufacturer if a mechanic parked his bubble gum in a bad
spot.
A number of years ago a big airliner crashed after losing an entire
engine and pylon in flight. The engine mount bolts were thoroughly
sourced, checked, tested, and the alloy composition tested. The bolts
should not have failed, but they did. Why? In the end, it was found
that it was the mechanics fault. Instead of following procedure, they
were short cutting and using a fork lift to make it easier to make an
engine change. This procedure over stressed the bolts and caused them to
fail in flight. Bad business. But being able to source those bolts
quickly and test them saved everybody a lot of hassle.
Regards,
John
On 6/14/2012 9:02 AM, Alistair Bell wrote:
>
> Now I recall the name of the book, Bentley!
>
> and its 25 Nm, not 28
>
> :)
>
> alistair
>
>
>
> John,
>
> I seem to recall that there is some sort of book or manual that has information about this, can't quite recall the name of it, something like Buntley, Bendy, Brimley?
>
> 28Nm/ 18 ft lbs
>
> :)
>
> alistair
>
>
>
>
> On 2012-06-14, at 6:00 AM, JRodgers wrote:
>
>> Is there a specified or a standard torque value for the bolt?
>>
>> John Rodgers
>>
>> On 6/13/2012 11:42 PM, Dennis Haynes wrote:
>>> It is very important for that lower alternator bolt to be properly
>>> tightened. If you can adjust the belt without loosening it, it is probably
>>> too loose. Give up the carriage bolt and use a P.C. 10.9 bolt, nut and
>>> washer. Yes washers also come in differing grades. As for the bracket studs,
>>> the nuts should match the grade of the stud.
>>>
>>> Dennis
>
>
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