Date: Sun, 8 Jul 2007 10:13:39 -0700
Reply-To: Bob Donalds <donalds1@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Bob Donalds <donalds1@VERIZON.NET>
Subject: Re: Sudden head gasket coolant catastrophic leaking
Content-type: text/plain; format=flowed; charset=iso-8859-1; reply-type=response
Fellow vanagon types
Benny is correct this is a classic problem with the WBX engine outer
cylinder head coolant gaskets. The failure of the rubber gaskets can happen
in the first few hundred miles or right away. I had this happen twice in my
many years first was early on just after start up and second was a guy that
blew both at once. I bring both up to make the point that there could be two
reasons for the failure. The way the head is installed is important to
prevent side loading of the gasket by this I mean that the gasket can be
pushed sideways as the head contacts the gasket due to the push rod tubes.
The tubes prevent the head from squarely engaging the head so the head as it
contacts the gaskets tend to go sideways. The most common location for the
gasket to pop out is the top of the block this is the first place the head
contacts the gasket and the direction the head is pushed.
To eliminate the gasket side loading we at the Engine Exchange have for
many years preformed a technique called the hokey pokey ( See your Bosch
automotive hand book for a full description of this term ) After the heads
is prepped and placed on the studs with the tubes in place I watch to see
that the inner gaskets remain in place. With one nut on the middle lower
studs I bring the head into contact with the gasket and adjust the push rod
tubes as I go. Once the head is in place but not tight against the gasket I
perform the (hokey pokey) wiggling of the head giving the gasket a chance to
find its place without any preload sideways. I then slowly tighten the nuts
in an even fashion. I only use the OEM style sealants provided in the Victor
Rintz gaskets the one with the blue cardboard backing.
The second reason I think new outer gasket fail is a sudden extreme rise in
pressure this is when the coolant system is not full and the expanding air
takes its toll.
The cracks between the seats can and do go much further than the eye can see
on OEM heads extending into the intake and exhaust ports. This is the
primary reason I stopped repairing OEM heads they crack and recrack in the
ports days and weeks after the heads are put back into service.
One final note
the new AMC heads should not be used as they come out of the box they need
professional attention to insure full service life
I offer these heads with all the updates for the same money or less than you
will find them on the net @ $450 each
fluffed, buffed and ready to be stuffed
standing by I remain
Bob Donalds
Boston Engine
where you get more than engines and engine parts
all rights reserved
----- Original Message -----
From: "Thomas Pfrommer" <pfrommer@PHAS.UBC.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, July 08, 2007 12:06 AM
Subject: Re: Sudden head gasket coolant catastrophic leaking
>I sent them out for inspection and if necessary, machining. One little
> hair crack was welded/machined between the valves, but not at the
> failure position of the gasket. I don't recall, whether it was the left
> or right though any more.
> Other than this hair, the heads were in good shape.
> I used the VW gasket set, and the head gaskets from there. Together with
> this black paste, I put them together, don't recall now the name, but
> will find tomorrow.
> Does the classic problem occur also that late after a rebuilt?
> Well anyway it seems I did not seal this head very well.
> Thanks for the help
> Thomas
>
> Benny boy wrote:
>> What did you use between head gasket and head?
>> How was the old head before you put this one back in? Was it cracked, was
>> it
>> tested?
>>
>> 2 reasons, bad sealing or bad/cracked head, period.
>>
>> A clasic problem!
>>
>> Ben
>>
>>
>> On Sat, 7 Jul 2007 16:54:21 -0700, Thomas Pfrommer <pfrommer@PHAS.UBC.CA>
>> wrote:
>>
>>
>>> Hi,
>>> oh man, I thought my van is running now. Did it for about 1500km, but
>>> today suddenly lost all its coolant, luckily a guy behind me on the
>>> highway called my attention right away. I did not see anything and the
>>> water temp did not yet rise. Well I pulled over the next exit. Again
>>> lucky was only 500m away, and then the temp gauge was rising quickly. So
>>> to the next parking lot and shut down the engine before it overheats!
>>> But what the hack was going on? Temp was always good, never reved it
>>> above 3000 rpm in these first 1500km. Oil pressure was good (yes the
>>> installed oil gauge is working fine ;-))
>>> And suddenly I loose all my water. After waiting to let the engine cool
>>> down a bot, I was able to look and lie underneath the engine and saw
>>> that the head gasket was pushed out for about 0.5 inch and thats where
>>> it leak. I added a bit of distilled water in the expansion tank and it
>>> pulled out right away right at this point (at the rear end of the right
>>> head, about midway between top and bottom of the head). What could have
>>> happened? When I rebuilt the engine, I torqued the heads to the specs
>>> indicated in the Bentley. I inspected the studs and they did not seem to
>>> be in bad shape so I did not replace them. Is this an indication that
>>> one stud broke? Yesterday I drove and was in a traffic jam and it was
>>> very hot, but everything worked fine, the water temp never rose more
>>> then just above the light position.
>>> I don't know but thats kind of weired. Perhaps not for you experts, but
>>> for me, as it drove without problems up to this point. I changed the
>>> expansion head cap just two days before as well, and all water was in,
>>> not indication of a small leak anywhere.
>>> Well I am quite frustrated now, I must admit, just thought I let you
>>> know, perhaps you have some advice. The thing is I do not have much time
>>> now to fix this major thing. I am quite busy at work. Do you Vancouver
>>> guys have a good recommendation, where to put it? I let it tow to
>>> Blenheim at 12th/Arbutus, just because I heard they are very nice guys.
>>> So I assume they don't rip me off. But perhaps there are other places?
>>> Anyway have a nice week-end and enjoy the sun, I have to recover a bit
>>> form this disappointment today though.
>>> Cheers
>>> Thomas
>>>
>>
>>
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