Date: Tue, 10 May 2011 21:23:05 -0500
Reply-To: Tom Lambas <twlambas@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Lambas <twlambas@GMAIL.COM>
Subject: Re: 2.1 rebuild - new nuts for case halves-thoughts for all
bolted connections.
In-Reply-To: <BAY152-ds1754F60D619B9FAF521E8A0870@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1
Thanks Dennis,
I have all my old case nuts, washers, and through-bolts soaking in naptha, I
ordered a bag of type 1 case assembly hardware also. At the very least, I'll
be able to use the 4 nice sealing nuts for the oil pump, and hopefully end
up using mostly new hardware.
BTW, I used almost all of your seat belt stuff. I was surprised at how worn
all the seat belts were in my van.
Cheers,
Tom in Minneapolis
On Mon, May 9, 2011 at 10:41 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:
> Here are two links that give some good information. One is how a clamped or
> bolted connection works and is indicative of case main bearing bolts and
> rod
> bolts. The other is the relative strengths of various grades of fasteners.
> Note the difference in strength of the A2 or A4 stainless as compared to
> property class 10.9. This class is the most common class used on the
> Vanagon. The real important stuff can be 12.9. In order for these bolted
> connections to work the nut and if used washers need to be matched. The nut
> has to be strong enough to stretch the bolt and get it under tension. The
> washer has to carry that load. If the washer distorts then the connection
> becomes loose.
>
> In addition to the strength of the material, finish, (zinc, black oxide,
> chrome, cadmium, organics) and lubrication, (oil, anti-seize, sealants,
> Loctite) will affect the torque required to reach a given clamp load. Black
> oxide, organics, and cadmium are often used on high strength fasteners as
> they provide more consistent torque tensioning. Zinc is sometimes an issue
> as it may cause hydrogen embrittlement. Some lubricants or wax coatings can
> reduce required torque by 40% or more. Consider that when thinking of never
> seize on your lug bolts.
>
> Many engine problems or failures come down to fluid problems or fastener
> failures. Internal head leaks, (gasses in coolant or coolant in cylinder)
> if not due to an actual cracked head are really a fastener failure. A
> problem is that engines will often be repaired or rebuilt without
> addressing
> the failed part.
>
> Dennis
>
>
> http://www.unified-eng.com/scitech/bolt/clamping.html
>
> http://www.tessco.com/yts/customerservice/techsupport/whitepapers/pdf/bolt_g
> rade.pdf
>
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Daniel Rotblatt
> Sent: Thursday, May 05, 2011 12:05 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: 2.1 rebuild - new nuts for case halves
>
> There have been several discussions on other forums about this.
> Essentially, if it's a torqued nut then the torque setting is defined by
> the
> type of nut and stud - stainless (or different grade nuts for that matter)
> require different to torque settings. Saying "stainless is not as strong"
> is incorrect - like different grades of nuts, it depends on the alloy of
> the
> stainless. I imagine that standard stainless nuts may be "less strong"
> then
> standard non-stainless nuts, but that is still a generalization. The
> alloys
> used in stainlesss (and there are many many alloys) give the metal
> different
> properties then carbon steel. There is even a problem changing the
> strength
> class (using grade 8 nuts/bolts when grade 5 are specified) - some
> nuts/bolts are specified because they are supposed to fail at a certain
> stress to prevent further damage to the engine - and of course there's that
> torque issue again.
>
> The upshot, is that if it's a torqued nut, use the manufacturer specified
> if
> possible. If you replace with stainless when not specified, you take a
> chance that the nut will fail. Doesn't mean it will, just that it may or
> may not be within proper specifications (thus Franks observation that he
> uses stainless hardware and does not have failure).
>
> Dan
> Los Angeles, CA
> '85 Westy Weekender
>
> On May 5, 2011, at 2:33 AM, Frank Condelli wrote:
>
> > I beg to disagree. All engines I have rebuilt here get
> > stainless hardware everywhere possible. Never seen any problems
> > related to the use of stainless hardware on the engine cases or
> > elsewhere. See here > http://www.frankcondelli.com/21engpcs.htm
> >
> >
> > On 2011-05-05, at 12:00 AM, Automatic digest processor wrote:
> >
> >> I sure would not be putting any stainless fasteners on it.
> >> they are not as strong ..
> >> stainless is not titanium or 'fautless' like people want to think it
> >> is.
> >
> >
> >
> > Cheers,
> >
> > Frank Condelli
> > Almonte, Ontario, Canada
> > '87 Westy & Lionel Trains (Collection for sale) Frank Condelli &
> > Associates - Vanagon/Vanagon Westfalia Service in the Ottawa Valley
> > Vanagon Stainless Steel Exhaust Systems BusFusion a VW Camper camping
> > event, Almonte, ON, June 09 ~ 12, 2011
>
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