Date: Mon, 10 Sep 2007 07:01:01 -0400
Reply-To: -------- <VW4X4@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: -------- <VW4X4@VERIZON.NET>
Subject: Re: cracked AMC heads question
In-Reply-To: <ed96608f0709092043m7c9789c0m2838a01913522c1b@mail.gmail.com>
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Leak test is not the only problem. If this crack should be to deep the
valve
seat could fall out. This will (i've seen this) break the valve, then,
break the
piston, and parts of the piston gets thrown into the crank witch
destroys the block.
All in a few seconds.
Chris Lisica wrote:
>Yeah, sorry, I'm talking about the cracks between the valves. I've heard
>that a hairline fracture is acceptable, but that one in my picture is pretty
>big. A leak test would be good.
>
>Hmmm, thanks for the advice. Some of those measurement numbers are scary! I
>have a line on a used set of German heads for $200, I may just go that
>route.
>
>Chris
>
>On 9/9/07, Scott Daniel - Shazam <scottdaniel@turbovans.com> wrote:
>
>
>>You're talking about the cracks between the two valves ?
>>Totally normal.
>>You 'could' get them pressure tested if you're worried,
>>You can also peen the cracks shut with a hammer and punch.
>>
>>Fwiw - ..judging by the corrosion where the water gasket touches this head
>>-
>>perhaps you might get away with head gaskets only.
>>
>>I would also test for valve sealing by filling the ports with gasoline or
>>kerosene, and see if they leak. I usually find at least one exhaust valve
>>leaking.
>>Then I have a machine shop do a valve job.
>>
>>And what I wanted to say about AMC heads - fwiw, I have one.....that I
>>installed new, and it didn't last, for head gasket sealing .....that
>>particular head is so far out of 'dimension' it's sick. Pure
>>junk. And
>>it was factory new. So I'd be careful about AMC heads, if nothing else.
>>
>>I'm finding it necessary to check how much the water gasket gets
>>compressed.
>>By my measurements the water gasket is 3.7 mm thick.
>>Put the head on temporarily ( with metal sealing rings at the top of the
>>barrels ) and measure the water gasket gap.
>>Iv'e seen it be 3.7 mm - thus no compression on the water gasket - and it
>>leaked after a thousand miles.
>>Iv'e seen it vary , like 4 mm on one end, 7 mm on the other, and so forth.
>>And I'd be real careful with AMC heads.
>>I'd rather have a good set of used non-amc heads and rebuild them, then
>>install them, than use AMC heads, unless the measure out nicely.
>>Scott
>>www.turbovans.com
>>
>>-----Original Message-----
>>From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
>>Chris Lisica
>>Sent: Sunday, September 09, 2007 7:35 PM
>>To: vanagon@GERRY.VANAGON.COM
>>Subject: cracked AMC heads question
>>
>>Volks,
>>
>>After purchasing my wife's 87 Westy project, I'm finally getting started.
>>I
>>knew the heads were messed up, but I was hoping for a simple head gasket
>>job. Upon closer inspection, and a few pictures in macro focus mode, there
>>appears to be a big crack on the one side. Any opinions? Is this head
>>reusable? What could cause such a large crack? The pics:
>>
>>http://wavanagon.googlepages.com/amcheads
>>
>>Please help enlighten an aspiring Vanagon mechanic. Thanks for any
>>advice/input/feedback/links/etc.....
>>
>>--
>>Chris
>>88 Vanagon GL (daily driver)
>>87 Westfalia (in progress)
>>
>>
>>
>>
>
>
>--
>Chris
>88 Vanagon GL (daily driver)
>87 Westfalia (in progress)
>
>
>
>
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