Date: Wed, 13 Feb 2013 09:58:26 -0500
Reply-To: "kenneth wilford (Van-Again)" <kenwilfy@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "kenneth wilford (Van-Again)" <kenwilfy@COMCAST.NET>
Subject: Re: Coolant Overpressurization / Head Gasket Leak
In-Reply-To: <vanagon%2013021222220913@GERRY.VANAGON.COM>
Content-Type: text/plain; charset=ISO-8859-1
Walter, if you are having a compression leak into the coolant it might not
show up until the engine heats up and the crack in the head expands.
As for getting stubborn cylinders loose I will tell you how I do it and it
work every time. Take a brass punch or drift and instead of trying to pry
on those cylinder liner ears, try to tap on it so that you turn the
cylinder a little to the right and then turn it back to the left. Do this
a couple of time and it will break the corrosion bond that is holding the
cylinder stuck fast. Then you should be able to pry in the center and the
head will come right off.
Hope his helps,
Ken Wilford
John 3:16
www.vanagain.com
On Tue, Feb 12, 2013 at 10:22 PM, Walter Houle <whoule@ecscontrols.com>wrote:
> Update: I'm still looking for the cause. I pressurized the cooling system
> with 15 PSI and didn't see any leaks. Next, I pressurized each cylinder
> with 100 PSI shop air and did not get any leaks into the cooling system,
> either. The torque on all the head bolts was OK at 33 ft lbs. I then
> pulled the low compression head part way off. it didn't look that bad,
> there actually was minimal corrosion underneath the outer gasket, and I
> didn't see any cracks. The cylinders were hard to pry off the head but
> they came loose with some effort with a pry bar and some PB blaster. There
> was some slight discoloration on the end of the cylinder barrels where
> they fit in the head. On to the next head. this time one head stud felt a
> little soft. It took about a quarter turn before the wrench clicked.
> That's as far as I got. I'm still trying to get the head all the way off.
> One cylinder barrel is stuck. I have tried soaking it in PB blaster and
> various pry bars on those little tabs to no avail.
>
> Any recommendations on how to get this cylinder loose? The engine is in
> the van and the van is in the garage so I am reluctant to try any heat.
>
> Thanks,
> Walter
> 1985 1.9 that has been unopened for 15 years ...
>
>
>
>
>
> On Sun, 27 Jan 2013 15:33:46 -0500, Walter Houle <whoule@ECSCONTROLS.COM>
> wrote:
>
> >I'll give it a go. First with the compressed air, then the stud check,
> >then pulling a head. Hopefully by then I'll know which way to go from
> >there. Thank you both for answers and advice.
> >
> >Walter
> >
> >
> >On Sat, 26 Jan 2013 19:38:47 -0800, Scott Daniel - Turbovans
> ><scottdaniel@TURBOVANS.COM> wrote:
> >
> >>worth a try.
> >>Might mention that coolant will come out if head nuts are loosened (
> >>drain coolant first )
> >>and that each nut needs to be resealed ..
> >>as they seal in coolant.
> >>
> >>S.,
> >>On 1/26/2013 7:02 PM, Dennis Haynes wrote:
> >>> You definitely need to do some testing to try to determine why the
> >>> compression is down on those two cylinders. Before pulling the heads I
> >would
> >>> check the torque on the head nuts. Internal leaks between the tops of
> >the
> >>> cylinders and heads are really due to failure of the studs to keep the
> >heads
> >>> down under those compressive/pressure loads and the temperature changes
> >of
> >>> the engine parts. I have repaired a number of internal leak issues by
> >>> re-torqueing the heads. The other failure point is cracked heads
> >allowing
> >>> the gasses into the cooling system. Coolant-hydrocarbon testing is not
> >>> always effective for diagnosing. As part of the leak down test, by pass
> >the
> >>> gauge and apply full shop air pressure to the cylinders (secure the
> >>> crankshaft securely) may make the leak obvious.
> >>>
> >>> Dennis
> >>>
> >>> -----Original Message-----
> >>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> Behalf
> >Of
> >>> Walter Houle
> >>> Sent: Saturday, January 26, 2013 8:08 PM
> >>> To: vanagon@GERRY.VANAGON.COM
> >>> Subject: Coolant Overpressurization / Head Gasket Leak
> >>>
> >>> The morning after the 300 mile drive home from BBB I noticed that the
> >>> coolant overfolw tank was full and overflowing a few drips. The
> >expansion
> >>> tank was also 100% full. I opened the pressure cap a little bit at a
> >time
> >>> and a lot of coolant pushed out - this on a stone cold engine that was
> >>> sitting for 12 hours. It looks like I have an internal head gasket
> leak.
> >>> The strange part was that the van ran strong all the way home and
> didn't
> >>> show any obvious signs of overheating. We stopped and checked it twice
> >along
> >>> the way, no drips, no smell, and no excess heat. The temp gauge was
> >over the
> >>> right edge of LED and it behaved normally, up a tad on the climbs, and
> >down
> >>> a tad on the descents, just like always. I did a compression test today
> >and
> >>> it was 170-170-140-150. Its been low on 3 & 4 like that for a while,
> >last
> >>> test was 6 months ago, but this is the first time I've had coolant
> >issues.
> >>> I will try a hydrocarbon sniff of the coolant and then a leakdown test
> >to
> >>> confirm. I've read a lot in the archives, and its looking more and more
> >like
> >>> its a compression leak, and it looks like it is only occuring under
> >load.
> >>> The heads are old and have never been off, original VW factory rebuild,
> >15
> >>> years and 75K miles ago.
> >>> Yes, this is way overdue and I should have taken care of this earlier.
> >>>
> >>> I am assumming new heads are in order, and I'm hoping that is going to
> >be
> >>> it. What about the rest of the engine? If it was pushing coolant away
> >from
> >>> the cylinders, it was doing it for a long period of time. WHat else
> >should I
> >>> be looking at?
> >>>
> >>> Thanks,
> >>> Walter
> >>> 1985 Vanagon 1.9 in San Diego
> >>>
>
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