Date: Wed, 22 May 2013 22:03:26 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: quick and dirty head swap-dennis' 2 cents.
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I know this sounds a bit crazy but pulling the heads should not be taken
lightly and a quick and dirty job usually just means you need to have a good
towing plan. In the grand scheme of things the outer gasket only holds the
coolant in and small leaks don't mean a tow home. What is critical is the
seal between the heads and the cylinder sleeves. If you actually sand
blasted, not glass or aluminum oxide blasted you may have removed enough
material to prevent the heads from sealing there. Hylomar or Loctite 508
(with activator) can help this seal hold if used carefully. I also use the
Hylomar on the green o-rings on top and o-rings at the base of the
cylinders.
The sealant that now comes in the kit works very well. Years ago it sucked.
I have also used the "Right Stuff" there along with a bunch of other
products. Permatex also sells a rubber gasket dressing, 85409. Don't bother
with epoxies and other methods to seal pitted heads. This stuff will stop
all leaks out there forever. You don't want to have to remove it. You have
to be careful using it. The head has to be assembled before it begins to set
or it will over compress and destroy the new gasket.
The most important point to success is the torqueing of the nuts. They
should really be replaced. If not, you need to carefully clean the threads.
Get a high quality bottom tap (10 x 1.5). Run to the bottom of each one.
Make sure the threads on the studs are clean also. Any friction on the
threads will result in the studs twisting as you try to get to the final
torque. Do NOT put anything inside the cap nut. Use a nickel based anti
sieze on the threads of the studs. Fully cover the threads, no drips or
puddles. Use the yellow sealant from the kit only on the nut flange. Use a
beam or dial torque wrench for the final tightening. Apply the torque and
hold pressure until the nut stops turning. You will feel when it right.
There is too much twist for clicker type wrenches to be reliable. If you get
a nut that never seems to tighten beware, it will only stretch so far before
breaking. Even if you stop it may break later while driving. These studs are
shot. The original spec was 37 ft lbs. VW later changed the spec to 41.
If the cylinders are disturbed after you get it running do another oil
change. After 1,000 miles do an oil test to make sure antifreeze is not
getting into the oil. I have learned that I now pull the cylinders and
replace the o-rings at the base of the cylinders. Antifreeze outside of a
sealed system, heated, agitated and mixed with air becomes extremely
corrosive. Those pits in the head were not cause of the gasket leaking. The
gasket leaked and as the heated coolant reached the outside air it corroded
the head and caused the pitting. Note there was no pitting anywhere else but
under that gasket. Long before you see it in the oil it will start
destroying the bearings. While the cylinders are out I also use them with
some lapping compound the clean the heads where the cylinders have to seal.
You will see the high and low spots. With the cylinders in you want to use
a good straight edge to make sure the cylinders are level and parallel. If
not the case is twisted and again you won't get a good internal seal. One
more cause of combustion gasses in the cooling system.
As important if not more than the type of antifreeze you use is the quality
of the water. I buy pre mixed or use distilled water. I no longer use the VW
Blue stuff or dexcool. My favorite is the late model long life diesel
antifreezes such as "Final Charge" or the G05. Once on the final charge
figure yo never have to change coolant again. Regular hose and water pump
replacements will take care of that. The expected service life is 6 years or
600,000 miles in heavy duty engines with a one-time supplement at the half
life. It also has wetting agents (required for diesel Sleeve cylinder
engines) so no Water wetter stuff is needed. The only down side is that the
wetting agents also eliminate water's surface tension. So if there is any
chance of anything leaking it will and you get a crusty orange trail to find
it.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Alistair Bell
Sent: Wednesday, May 22, 2013 10:50 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: quick and dirty head swap
I'm going to ignore Neil's petrifying pun :)
Tom,
I'm in the fortunate position of having a spare engine from which to
scavenge parts, and a collection of odds and ends gathered over the years.
But here goes with an "off the top of my head" additions to your list:
(oh, one caveat - with my head swap, I am purposely trying not to get
dragged in deep. You know, like doing some minor work on an old house....)
- engine coolant pipes - watch out for rusty pipes around engine
- engine cooling hoses - ditto on having a good look at the ones around
engine
- head/pushrod tube plates - what ever you call them, the pressed steel
protection under pushrod tubes. The tabs that affix to exhaust bolts might
be rusted off. I need to weld mine up.
- exh manifolds and fasteners if needed
- water pump - right on cue, mine WP is making noise and has some play. I
have spare sitting waiting.
- fuel line replacement - good time to do it of you haven't already?
- clutch replacement - see how the job expands?
- that conical gasket between throttle body and intake plenum is NLA up
here. Looks like a job for some sealant.
- valve adjusters - the threaded feet on the rocker arms. Some of yours
might be worn badly, might be a good idea to replace, or it might not be a
good idea. I don't know.
- I have a tube of "The Right Stuff" sealant in addition to the Renszoil
that came with the gasket kit. I haven't decided which to use on the head
gaskets.
- degreasers - solvent of choice for tanking parts, brake cleaner or the
like for getting sealing surfaces totally grease free.
The marble slab as a crude lapping plate worked quite well. I didn't take
pics of a straight edge on lapped face, but it was pretty flat. Mind you I
only lapped long enough to take the excess JB Weld off.
And parchment paper worked great. No sticking to the JB at all. Has a little
more heft than wax paper.
And now it just occurred to to ask - are you going to try and re-use your
old heads? If so, you should check the valves (need a valve compressor or
use a make-shift set up as I did) which involves visual inspection and a
little measurement (see Bentley).
I'm sure there must be more.
cheers
alistair
On 2013-05-22, at 6:51 AM, Tom Carchrae wrote:
> Thank you so much Alistair! You say 'quick and dirty' - but that
> looks pretty clean to me.
>
> I am still looking with fear at my van and have not yet had the guts
> to pull the heads off. I'm going to order a gasket set sometime soon.
> Aside from JB weld, the gasket set (
> http://www.busdepot.com/025198009b ) - is there anything else good to have
on hand?
>
> Tom
>
>
> On Tue, May 21, 2013 at 10:43 PM, neil n <musomuso@gmail.com> wrote:
>
>> Marble-ous!
>>
>> I know. < groan >
>>
>> I bet this job will hold up longer than you need.
>>
>> Nice to see the detail in the images!
>>
>> Neil.
