Date: Tue, 13 Feb 2007 17:08:10 -0500
Reply-To: Mike Collum <collum@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Mike Collum <collum@VERIZON.NET>
Subject: Re: My 2 cents on head leaks and rubber studs
In-Reply-To: <20070213210603.38469.qmail@web38909.mail.mud.yahoo.com>
Content-type: text/plain; charset=ISO-8859-1; format=flowed
It never threw a rod. A valve seized in it's bore (didn't hit a piston)
and a pushrod bent. It had an overheating problem before that that I
attribute to a head that wasn't sealing.
Mike
gary hradek wrote:
> Mike,
> So maybe it stretched when the engine blew???
> The simple explanation is that when the rod let loose
> and the piston hit the top of the head, that is when
> the bolt stretched. Why do you need to explain it
> any other way???
> --- Mike Collum <collum@verizon.net> wrote:
>
>> When my '84 was given to me back in '91, it came
>> with a blown engine.
>> One of the head studs on that one had stretched to
>> the point that I
>> could wiggle the capnut and it was screwed all the
>> way down.
>>
>> Mike
>>
>>
>>
>> gary hradek wrote:
>>> I am not so sure about just how much of a problem
>> this
>>> stretching stud idea is. First of all when does
>> all
>>> this stretching occur. I think it is a bit of a
>>> stretch to say that the stud acts like a spring.
>>> I think the stretch occurs when you torque the
>> head
>>> down or perhaps when you over torque. I agree it
>> is
>>> a good idea to replace studs and nuts when the
>> threads
>>> look suspect or perhaps with a major rebuild but
>> for a
>>> simple head leak, keep it simple. If it leaks
>> again
>>> it is more likely to be caused by poor
>> installation
>>> than stretching studs. Gary
>>>
>>>
>>> Date: Tue, 13 Feb 2007 13:10:35 +0000
>>> From: Dennis Haynes <dhaynes@OPTONLINE.NET>
>>> Subject: Re: My 2 cents on head leaks. Old hash
>> I'm
>>> sure...
>>>
>>> I have mentioned the studs on many occasions.
>> Anytime
>>> you have internal
>>> head gaskets leaks, the initial cause was the stud
>>> failing to hold the
>>> heads down under load. To simply replace gaskets
>> or
>>> heads without
>>> addressing the stud failure is just asking for a
>>> repeat. The nuts should
>>> always be replaced and new studs should be
>> considered.
>>> Not only can they
>>> corrode and break from stresses they are designed
>> to
>>> act as springs. And
>>> like a pen spring, once it is over extended they
>> will
>>> not return to
>>> their original state. Proper lubrication of the
>>> threads and a suitable
>>> sealant on the nut flange is important to
>> obtaining
>>> the proper pre-load.
>>>
>>> Dennis
>>>
>>> ----- Original Message -----
>>> From: Jeff Hogue
>>> Date: Tuesday, February 13, 2007 7:49 am
>>> Subject: My 2 cents on head leaks. Old hash I'm
>>> sure...
>>> To: vanagon@GERRY.VANAGON.COM
>>>
>>>> I too have rebuilt/resealed many (maybe hundreds)
>> of
>>> boxer
>>>> engines over the past 23 years. I don't hear any
>>> talk about the
>>>> head studs being stretched. The heads are held to
>>> the block with
>>>> very little torque, and the hardware integrity is
>>> very
>>>> important. Just compare a new stud with a
>> previously
>>> used one,
>>>> maybe on that has been torqued 2, 3, 4 or more
>> times
>>> and it's
>>>> obvious that they do stretch. Also, sealer on
>> these
>>> head gaskets
>>>> is very important, I use perm-a-tex ultra grey
>> and
>>> have never
>>>> had a problem. Ever. But be very careful not to
>> use
>>> too much.
>>>> This is not a case of lot is good, more is better
>>> and too much
>>>> is just right, like my fathers view on
>> horsepower.
>>> On the top of
>>>> the block I use the same ultra grey. Be
>> absolutely
>>> certain to
>>>> clean, clean, clean the sealing surfaces, use
>>> alcohol base
>>>> cleaner or something that won't leave a residue.
>>>>
>>>> I'm sure this has been bounced around plenty, so
>>> forgive me for
>>>> the broken record... That's my 2 cents on the
>> leking
>>> head gasket
>>>> talk that seams to haunt the list.
>>>> Jeff Hogue
>>>> 84 Westy
>>>> 87 Syncro Doka
>>>> 8? Iltis Diesel
>>>> 03 Jetta TDi Wagon
>>>> 90 son
>>>> 94 daughter
>>>> 62 wife.....
>>>>
>>>
>>>
>>>
>>>
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>
>
>
>
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