Date: Mon, 26 Sep 2011 08:02:49 -0500
Reply-To: John Rodgers <inua@CHARTER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Rodgers <inua@CHARTER.NET>
Subject: Re: Question and parts request.
In-Reply-To: <183c01cc7c17$a4ef73f0$6401a8c0@PROSPERITY>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
When I was working for an airline in the maintenance shop, all torque
jobs required that the torque wrench be calibrated by the tool room just
before the torque job could be done. It was always surprising to me how
easily even a high quality torque wrench got out of calibration. One
thing I learned over the years was how critical the sourcing of hardware
was. It was far to easy for junk bolts, nuts, etc. to filter into the
system. Even back in the day when we had a good manufacturing base in
the US it was at times problematic, but in todays environment, where so
much of our manufactured goods come from foreign shores, the problem is
much worse. The sheer volume of stuff coming in makes it hard to track.
John
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com
On 9/26/2011 1:43 AM, Scott Daniel - Turbovans wrote:
> on the other hand VW stretch bolts are quite inexpensive.
>
> - Ten head bolts for a VW diesel for as low as $ 1.50 each.
>
> come to think of it ..on a 1.9 diesel the spec is so many ft lbs..
> then two 90 degree turns.
> I can seldom get that second full 90 degree twist ..it sure seems like
> something is going to break or strip or give.
> I have bolts sitting by a blown engine I have ........
> one of these days I'm going to put head bolts in that block and just
> turn and twist on those bolts until they are either very fully turned
> to where they belong,
> or something gives.
> On those it's scary feeling sometimes.
> Feels like you're putting 200 ft lbs on them ..like something has to
> give.
>
> 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 11:07 PM
> Subject: Re: Question and parts request.
>
>
>> Turbine engines have pretty much taken oven in the aviation world,
>> but there a lot of radial engines out there still. An interesting
>> thing about radial engines. If it's a single bank or row of
>> cylinders, there is only one crank throw - doesn't matter if it's a 5
>> cylinder, 7 cylinder or 9 cylinder engine - one crank throw. So how
>> do they get 9 cylinders onto a single crank throw. That is the
>> question. Well, they do it with a Master Rod. A single rod that has a
>> bunch of holes in it to which all the other rods attach. The only rod
>> to travel in a perfect circle is the master rod. The rest, because of
>> the way they attach, the rod end travels in an ellipse. What is
>> really interesting is the master rod is held on there with stretch
>> bolts. In some cases the cranks shaft is two part and a clamp holds
>> them together - but again - it's stretch bolts that hold the clamp
>> tight. They are high torque, one time only use. If you over torque ,
>> you have wasted a whole lot of money because those puppies cost
>> dearly. Stretch bolts to me were always kind of scarey, but the
>> engineers put them in all kinds of places and claim they are good.
>>
>> John
>>
>>
>> John Rodgers
>> Clayartist and Moldmaker
>> 88'GL VW Bus Driver
>> Chelsea, AL
>> Http://www.moldhaus.com
>>
>>
>> On 9/25/2011 10:20 PM, Scott Daniel - Turbovans wrote:
>>> 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 ..
>>
>
>
>
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