Date: Mon, 7 Apr 2014 10:52:03 -0500
Reply-To: JRodgers <jrodgers113@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: JRodgers <jrodgers113@GMAIL.COM>
Subject: Re: The Head is Off, Assume Cracked?
In-Reply-To: <CAAymtAbnq8k6W7fXUc1WFOq3gADRjhZHg9N6TzfxBKLKy-+SEg@mail.gmail.com>
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Paul,
With the head out - take it to a machine shop an have them clean it
thoroughly, then do a dye-penetrant check for cracks. That test will
show for sure if cracks exist!
John
On 4/7/2014 9:45 AM, Paul Smith wrote:
> This thread really started about a week ago, as detailed in my post on
> March 30th: "Replacing the Head Gaskets (Maybe the Head)?" - so I won't
> repeat it all here. The vehicle is an 1989 Westy, 2.1 WBX, started with
> white smoke a few minutes after startup, returned to the driveway and later
> when I pulled the spark plugs I found coolant in the passenger side front
> cylinder.. I did manage to get the passenger side head off, going slowly
> and carefully and with the expected pain points (exhaust system, etc.). The
> problem cylinder was the front cylinder and it was stuck firmly to the
> head, requiring use of the methods noted in Bentley and on this list to
> finally free it. The sealing o-ring at the top of the front cylinder looked
> damaged (or deteriorated) compared to the same o-ring on the rear cylinder,
> which appeared to be in good shape. I thought I might have a cause, except
> that the compression gaskets in the head both looked good, no apparent
> damage or discoloration. I have no evidence that the coolant system was
> being pressurized by exhaust gases, only somehow coolant was entering the
> front cylinder. I don't see any cracks in the cylinder head combustion area
> (hairline or larger), although I have not cleaned all the carbon deposits
> off. Both exhaust ports look about as expected, fine coating of black
> carbon, with the front port slightly "damper" or more oily. The intake
> ports revealed an oddity. The rear (good) intake port looked about as
> expected, clean metal with a light oily sheen. The front (bad) cylinder
> intake had a coating of grey slimy stuff covering a good part of the back
> curve of the intake passage and up around the valve guide area. I was
> wiping it out without thinking how odd it was (long day) when I stopped. It
> seems unlikely that coolant would be blown up into the intake from the
> cylinder (valve is primarily open on the downstroke), but coolant leaking
> into the intake passage would certainly be sucked into the cylinder. If it
> were being sprayed in from crack in the head it might also form a coating
> on the hot intake passage walls. I guessing that this may have been
> developing over time, as Dennis Haynes mentioned. I took a close look at
> the piston tops - the rear had a light coating of combustion/carbon
> deposits; the front piston had some, but is fairly clean (steamed clean?)
> in the center portion. The cylinder walls look good in both, smooth,
> unscored and not scorched or discolored.
> Has anyone experienced a crack like this in the head into an intake
> passage? I can't see anything obvious, but without removing the valve and
> getting a good view angle I might not. Still might not find anything
> visually in any case. I tried briefly to block all the coolant passages and
> apply pressure to detect a leak - couldn't get a good seal. All this is
> being done in my driveway, no garage, so my shop facilities are limited. I
> can't understand how a grey coating could be formed in the front cylinder
> head intake passage without a leak of some kind, along with the clear entry
> of coolant into the cylinder. Both intake tubes upstream of the head seem
> fine (the same). The driver side intakes are also fine.
> It seems like a replacement head may be the best option at this point. I'm
> not sure I can find the cause, although it pretty clearly appears to be in
> the head. I would rather install a new head than try any partial repair or
> patch. Then if I get curious enough I can pull apart the bad head and see
> what I find.
> Thoughts?
>
> Thanks,
> Paul
>
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