Date: Sun, 25 Sep 2011 20:20:00 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Question and parts request.
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Hi John..
I find critical fasteners like thee one that holds a propeller on
fascinating.
I have worked on avionics on aircraft..
and we always torque the 4 radome screws to so many inch lbs., for example.
on WV diesel 1.9 engines..there's a stretch bolt holding the timing belt
sprocket onto the flat noise of the crankshaft ( very dumb design I
think..........no, I know.......because I've seen it screw up ..
and other engines such as Mercedes, Volvo, and Subaru don't do it that way
..which is an example of why I don't think engineers are so smart all the
time ..) ..
anyway I call that bolt........... ..a one time use only stretch bolt, the
Jesus Bolt ..
cause if it screws up ..
it's all over. lol
Scott
----- Original Message -----
From: "John Rodgers" <inua@CHARTER.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, September 25, 2011 5:51 PM
Subject: Re: Question and parts request.
> Scott,
>
> I have done my share of wrenching in the aviation industry. We lived by
> the specs. Some were from the engineers - those we lived and died by.
> Some were the standard torques applied to hardware not involved in
> safety issues. And there were times when I definitely use the"Calibrated
> Wrist" - each had it's place. When I have new tires mounted - the shops
> always use pneumatic wrenches to set the nuts or bolts - and as soon as
> I get home, I always re-torque them by hand with my own torque wrench.
> Invariably the shop torques are wrong if Bentley is right. Either to
> loose or to tight. But one should not go nuts over this. I think specs
> should be observed. You don't want your propeller flying off in
> mid-flight, nor your tire and wheel passing you as you go down the road.
> If you change a tire on the road, and use reasonable technique - you can
> get safely home where you can apply proper torque. In any case, I think
> you are absolutely correct about applying even torque all the way
> around, and doing it in a tightening pattern so stresses are kept at a
> minimum. You can actually flex parts out of shape if that rule is not
> observed. The even torque can prevent vibrations from occurring as well,
> preventing parts failure of having something fly off as you go down the
> road.
>
> Just my $0.02.
>
> John
>
> John Rodgers
> Clayartist and Moldmaker
> 88'GL VW Bus Driver
> Chelsea, AL
> Http://www.moldhaus.com
>
>
> On 9/25/2011 6:19 PM, Scott Daniel - Turbovans wrote:
>> Hi john,
>> nice to see your note.
>> what version of Bentley are you using ?
>> mine is the 1980 to 91 version.
>>
>> and isn't this funny ..
>> on my Bentley it says 123 ft lbs for wheel nut torque on pg 46.6
>> and 133 ft lbs on page 42.4
>> so ...........see, even Bentley doesn't know what they are saying
>> sometimes.
>>
>> as for your 1333 ft lbs..
>> better not try that.
>>
>> well......
>> after I wrote that I tighten my by hand , with a half inch breaker bar
>> and
>> 3/4 socket until they are good and tight ..
>> next thing I see is someone questioning that ........perhaps a little
>> light
>> I don't know what I am doing...
>> and as I said, I have tightened tens of thousands of wheels onto cars
>> ,working on cars 'just forever' , starting in 1964 ...........and most
>> of my
>> life full time.
>>
>> but I hesitate to share real solid 'back yard' methods ..
>> because .............people can be so stupid they'll take that and
>> make it
>> into like I don't know what I'm doing..
>> so I am cautious about sharing what really works for me sometimes.
>> And believe me ..If I am not really sure about something I'll put on a
>> qualifier like 'I believe'. I' careful about what I write ..and sometimes
>> I'm cautious about what I write ...like sometimes people take one tiny
>> thing and go nutty with it.
>>
>> here's what I suggest ..you get a ......and I did suggest half inch
>> drive
>> click type torque wrench that does up to 150 lbs ..
>> and tighten the lug nuts in the rear to 133 ft lbs..
>> Then see how easily the unscrew with your stock lug wrench under the back
>> seat.
>> and I will too.
>> I expect that's going to be really, really tight.
>> And we'll see.
>> I can tell you this......in tightening head bolts with an say
>> ..........17
>> inch long torque wrench ..that is really, really tight feeling ...so ,
>> and
>> I'll try it myself...133 ft lbs seems really awfully tight to me.
>> But I'll check.
>> OK.........I just did.
>> As I expected 133 ft lbs is awfully tight.
>> I tighten them to about 85 to 90 ft lbs.
>> That they are evenly tightened is very important.......all very close
>> to the
>> same,
>> and in a star pattern of course.
>>
>> But if you don't trust yourself, then do what's in the book.
>>
>> Here is what I suggest..
>> tighten them very firmly, and evenly, by hand with a 1/2 inch breaker
>> bar
>> to roughly 90 ft lbs.
>> Check them again in a few days after driving some.
>> Check them twice a year.
>> They won't go anywhere if you tightened them evenly and pretty firmly.
>> Wheels are not coming off from being tightened to say only 70 ft lbs
>> instead
>> of 133 ..
>>
>> and of course...develop your own 'feel' for stuff..
>> and check your work.
>> heck........don't even trust tires stores..
>> here's a typical story ..
>> Road & Track magazine was doing a several day test drive on a hot turbo
>> volvo sedan about 5 years ago.
>> A pretty new car. They had just had it serviced.
>> they got a flat tire.
>> All the kings men and all the kings horses..
>> the people driving the car, the tow truck driver, a CHP .nobody but
>> nobody
>> could get the flat tire's lug nuts off.
>> It cost them about $ 500 in towing and repairs.
>> Likely because some dealer tire jocky impacted the nuts on with an impact
>> gun to 400 ft lbs....
>> just do careful work
>> and develop your own feel for things..
>> and always, always check your work ..
>> twice even .
>> and if anyone touches your van ......for anything...check their work.
>> I've loaned a van to someone and they went to get gas, the pump jockey
>> stuck
>> the ignition key in the gas cap and bent it ..
>> don't trust anyone......and check your own work several times even.
>> and develop your own feel for what works. Just make 'em very tight ..
>> and use a toque wrench if you feel you need too..
>> and if you want to take to 133 ft lbs..
>> go right ahead. But make sure you can get it undone with the van's stock
>> lug wrench, if that's what you plan to use if you get a flat tire.
>> 'engineers' ..
>> the 'real world' is very far away from 'engineer's world' quite often.
>>
>> just do good careful work.
>> Scott
>>
>>
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "John Rodgers" <inua@charter.net>
>> To: "Scott Daniel - Turbovans" <scottdaniel@TURBOVANS.COM>
>> Cc: <vanagon@GERRY.VANAGON.COM>
>> Sent: Sunday, September 25, 2011 3:22 PM
>> Subject: Re: Question and parts request.
>>
>>
>>> Scott,
>>>
>>> My Bentley says about wheel torque values:
>>>
>>> 1980 up to Nov 1984 - 170 Nm/125 ft-lbs
>>> From Nov 1984 - 180 Nm/1333 ft-lbs
>>>
>>> If one doesn't use book values - what would one use. I know for many
>>> "bolts" there are "standard" torques, but I wouldn't think that would
>>> apply to lug bolts/nuts. Those values are what they are as determined by
>>> the engineers. I only hope they got it right. By Guess and By Golly is a
>>> bit scarey!
>>>
>>> John
>>>
>>> John Rodgers
>>> Clayartist and Moldmaker
>>> 88'GL VW Bus Driver
>>> Chelsea, AL
>>> Http://www.moldhaus.com
>>>
>>>
>>> On 9/25/2011 4:28 PM, Scott Daniel - Turbovans wrote:
>>>> ( does anyone really take the wheel lug nuts to 123 ft lbs ? ..that is
>>>> really, really tight. )
>>>
>>
>>
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