Date: Sun, 13 Feb 2011 18:49:52 -0800
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: General engine bolt/nut sizes
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HI Joe..
I like that ...'overthinking it' ..
I think you are some for sure.
I've done hundreds of air-cooled vw engines ..
I just put them back with the standard fasterners as long as things are in
good shape.
the other's poster on how there at not any stretch fasteners or unusual
stuff on air-cooled engines was basically right on.
just do good careful work. That's where you really get the result...good
careful work.
I don't think gmeran engineers are infalable at all.
I see where they make things so they will work right when the ARE right
only, can't think of a good example right now, but they do that a lot. Too
'theoretical' . Low on the practicality aspects of design in my opinion,
here and there. Overall I think pretty highly of the Vanagon body/chassis
....very few complaints there.
'underengineered' ..don't get me started. I can show you how the AAZ turbo
diesel timing belt sprocket, a totally, totally, critical part ...is really
an extra dumb design..for example.
lol...first time I saw how the alternator is mounted on a Type IV air-cooled
VW engine..
looks to me like at the very end ..they said 'holy cow ! ..we forgot the
alternator ...where are we going to put that ?'
About all I ever really use from the book is the torque specs.
and for sure ..
previously dissasebembled can make things quite tricky unless you've done
those a lot.
here's a tip ....
if the distributor drive shaft slides up for any reason .....there are two
shims under it that can tilt and jam in the distributor drive gear on the
crankshaft...a real mess.
to prevent that, always have the distributor installed in place, so that
little shaft can't move up accidently.
and the book will show you installing the distributor last step on an
asembled engine.
I never do that ..
as soon as I have the crankshaft in the left case half, I install the
distributor immediately ...so nothing can slip out of place.
to give you an idea how easily this can happen...on some rebuild long block
instructions, it says 'Do Not Rotate the Engine until the distributor is
installed !!'
it's a classic 'gotcha on air-cooled engines'
last comment ..
there are a few places where if you don't put X part on before part Y ...
you're in trouble...assembly order is very important on them.
An example, I say, of how I find german thinking to be very 'rigid' ...
has to be one way and only that way.
But we love 'em.
scott
www.turbovans.com
----- Original Message -----
From: "Joe Luther" <jluther@ALFONS-HAAR.US>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, February 13, 2011 3:42 PM
Subject: Re: General engine bolt/nut sizes
> Thanks again for the reply. I have access to the 8.8 grade as well as
> 10.9
> and 12.9, A2E coated and standard. I've worked with high speed metal
> container manufacturing machines for 25 years, some US based and others
> German made. When getting our US based equipment certified for the CE
> mark
> back in the 90's TUV specified Nyloks because of the +/- 30% torque value
> of
> conventional fastening components when surface texture and lubrication of
> mating surfaces were considered. We also had to use 1/2" Lexan guarding
> for
> ejection hazards in case the Nyloks weren't enough.
>
> All this has stuck with me over the years and thinking about the VW engine
> and the design just led me to wonder whether I could get better life out
> of
> everything by considering some upgrades. Working for Germans for 12 years
> has taught me that they usually don't underthink or underdesign things but
> that is gradually changing, IMHO.
>
> But, as I mentioned earlier, if you've had 30 years of good experiences
> from
> straight torque then I'm overthinking this and it's one of the big reasons
> I
> joined the list....you guys have done this and I haven't so I'm here to
> listen and learn what has worked.
>
> Joe
>
> -----Original Message-----
> From: Mike [mailto:mbucchino@charter.net]
> Sent: Sunday, February 13, 2011 5:46 PM
> To: Joe Luther; vanagon@GERRY.VANAGON.COM
> Subject: Re: Re: General engine bolt/nut sizes
>
> Fasteners are normally re-used as long as they're not corroded or stripped
> in any way. I have seen some very old VW washers crack upon re-use due to
> age-tempering/ work-hardening issues.
> I only made the 'out-thinking' comment because it's so typical of so many
> 'rebuilders's of VW's, more often than not.
> Yes, technology has advanced over the past few decades, but not too much
> in the areas you're considering. I'm an FAA-licensed, fully-experienced
> Airframe and Powerplant mechanic, and I can think of many improvements
> possible in the VW designs, including the types of fasteners used.
> Nylock nuts are not appropriate to high-temp applications like an engine.
> Check the specs and you'll see that. Only High-temp (all metal) locknuts
> are applicable there.
> Do you have access to 8mm, grade 8.8, all-metal locknuts? If so, use
> those, otherwise stock wavy washers and plain nuts are fine.
> Aviation hardware would be best, but is very expensive. Some hi-po
> builders use 'raceware' - http://www.raceware-fasteners.com/photo.htm)
> Don't be nervous, the case edge bolts aren't under a lot of stress or
> movement. The Type 4 main case tie-bolts are critical fasteners, but if
> you
> look at them closely, you'll notice that they are very special,
> application-specific bolts and washers, the Type 1 used studs there. The
> type 4 is vastly improved and updated by VW engineers over the years, and
> the Vanagon engine contains all of these improvements.
>
> Mike B.
>
>
> I'm really not looking at out-engineering or out-thinking VW but there is
> newer technology in many areas since 1983 (such as the self locking nuts)
> and I thought it good to ask the question whether others found it made
> sense
> to use it here. I'm glad to hear you've had such good results relying on
> straight torque for performance, in mission critical moving machine
> applications I've always had to use Nylocs or other self locking hardware
> so
> going by straight torque makes me a little nervous, I'll just have to get
> over that.
>
> Joe
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