Date: Tue, 10 May 2011 21:38:53 -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: <BANLkTik-UdbBAd4T0TTAZuEYnQE=qdua4g@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Oops, forget about the seat belts. I got them from Max Wellhouse.
On Tue, May 10, 2011 at 9:23 PM, Tom Lambas <twlambas@gmail.com> wrote:
> 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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