OTOH, in 3/4 million miles in wasserboxers, I've never had a head gasket
(combustion) let loose, but in about 200,000 miles in VW inline 4s, I've had
two failures.

Just sayin'

Karl Wolz

|-----Original Message-----
|From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
|Scott Daniel - Turbovans
|Sent: Thursday, April 22, 2010 1:25 PM
|To: vanagon@GERRY.VANAGON.COM
|Subject: Re: Water Cooler System Design Flaw Workaround?
|
|re
|I'm thinking about replacing the purging screw on the radiator in front
|with
|a Hose nipple and some kind of automatic purging scheme?
|
|I've had a plan in the back of my head for just that , for years.  Know
|exactly how I'd do it, what parts I'd use, when it would be 'active' etc.
|however..
|I haven't found it necessary.
|I don't find bleeding to be a big ordeal, or something that absolutely has
|to be done 105 % thoroughly and correctly every time you open the cooling
|system in any way.
|Sure...........some bleeding should be done, at the radiator.
|And *for sure* if it is ever necessary on a regular basis, something else
|is
|going on, like exhaust gases are sneaking into the coolant at the head or
|head gaskets, which is a pretty common failure.
|
|also ....the way it's designed ...
|what I have noticed for years and years about german-designed systems, is
|that they are deigned to work right when the ARE right ..
|and nothing in between.
|for example....I see a TDI  engine in a Golf car where the poser steering
|and water pump are driven by the same v-belt.
|PS is not a critical system ....but water pump drive is.  You could have
|your power steering system leaking badly.....
|and be on a trip for from any parts stores, , or not have the funds to deal
|with it just then ...
|and your car is unusable becuse a non-critical system is out.  That's not
|very wise design in my opion.
|  And I see it over and over in german and Vanagon design all the time.
|
|I like what one guy said to explain why it's so hard to replace the
|waterpump in a vanagon with the engine in the car ...
|he said 'they gave the engineers 30 days to come up with the waterboxer
|design."
|
|he's joking of course ...but that kinda fits.
|If you are bothered by the radiator bleed screw system ...
|what do you think of the completley joke head gasket system ??
|
|here's why I say it's a joke ( never mind that the evidence of what happens
|with wbxr head gaskets shows that they are not a super reliable design )
|On 'all other cars' .......combustion sealing and coolant sealing are both
|addressed by one very well made, flat gasket, that is held down onto the
|engiine block by thousands of pounds of force, and the bottom of the head
|is
|flat, and it sits on a flat box.
|
|in the waterboxer .......which is PURELY a converted air-cooled design...
|combustion sealing is handled by the metal rings on top of the cyldiner
|barrels.....and they sit agains the head...
|those metal rings are the only thing that seal combustion into the
|combustion chambers.  They seem to work 'all right' most of the time ...
|'most of the time' ....
|and the heads are not held down by a lot of force, just 8 studs per head,
|with nuts torqued to 37 ft lbs.
|In contrast...on a VW inline four diesel engine ....one nice solid flat
|gasket, flat-bottomed head, flat cast block...
|after the intial torque of ....around 60 ft lbs ...you turn the bolts a
|quarter turn more, then another quarter turn ...
|and by the second qtr turn you are pulling on your breaker bar so hard it's
|flat scary, like surely something is going to break.
|And it's 10 head bolts ...the force on the head gasket has to be thousands
|and thousands of lbs of force. It ain't going anywhere baby.
|
|so anyway ...the combustion sealing of waterboxer heads is .......rather
|casually done, and based directly on what they did with air-cooled engines.
|and if some pressure leaks past those metal rings in an air-cooled ....so
|what, it pops a little under load. In a waterboxer when it does that ...
|and it does happen fairly commonly ...
|exhuast gases displace the coolant in the engine .....and coolant doesn't
|ciculate then...
|and you get hot engine, cold radiator ....just like the main pipes were
|blocked, but that's not it.
|
|so that's the combustion sealing ....really rather weak, but we get by with
|it somehow.
|
|now the coolant sealing.
|to not have the bottom of the head flat, so there is only one level sealing
|surface is really dumb !
|and is an example of 'engineering thinking' ...'in theory' it should be
|fine. In the real world it is not.
|There are countless things designed by engieers that should work just fine
|in theory, but don't.
|
|the coolant sealing ..
|normally the coolant is sealed where it passes from block to head by a flat
|head gasket held down with extreme force.
|not in a waterboxer engine.
|The heads bottom out on the top of the barrels...
|and they are suppossed to fit down far enough to compress the outer rubber
|water gaskets 'just the right amount.'
|
|it is not hard for minor vairations in cylinder heads, or how the barrels
|fit in the block for that gap to be either too large, or too small, or even
|tilted...not right on one end of the head, but right on the other.
|
|The first time I found out from a VW dealer tech that when you run into
|that
|...'you try another head' I was just appalled, since they invented
|standarized car parts in about 1925....so any head fits right on any block.
|It was big deal, Might have been 1918...they drove 3 Buicks to the New York
|World Show or whatever it was, took them all apart, scrambled all the
|parts,
|and assembled the 3 cars and they all worked.
|
|so given that ...if one head fits better than another on waterboxer
|heads.....man, is that silly.
|
|That comment from the VW dealer tech was almost 20 years ago. The guy said
|'put the bare head on ( with the metal rings in place ) and measure that
|gap
|( where the outer rubber gasket goes  ) and if it's too small, "try another
|head."
|
|so I do that on every head job. I find them not right now and then. Too
|small, and it will pinch the gasket and it will leak before it should ,
|like
|not in 6 years, but in 2 years.
|Too big a gap...and it won't really seal.
|
|it gets worse.
|Say you find the dimension is not correct. And you'd like material macined
|off the bottom of the head...say it's too tight on one end, but right on
|the
|other end.....
|'the problem there' is ....machine shops surface heads referenced off the
|top of the head. they make the bottom of it exactly parrallel to the top of
|head.  That is not what a waterboxer head needs.
| It would need to be machined relative to where the metal rings sit inside
|the combustion chambers.  Not something regular machine shops are used to,
|or can even, do.  I had one done by an old air-cooled guy ....but it wasn't
|easy.
|
|my point is ....the waterboxer cooling system is 'demanding' let's say.
|Not like some old front engine, front radiator say, older toyota pick-up
|truck where having it mostly full at all will do the job.
|Waterboxer vangons need the entire cooling system to be working quite well.
|
|and compared to the silly head gasket set up ...the bleed screw in the
|radiator is no big deal.
|
|it's the nature of having a water-cooled engine in the rear, and radiator
|many feet away in the front..........that the system will be less
|idiot-proof, or neglect-proof and more demanding. .
|I can't even think of another car right now with that layout - rear liquid
|cooled engine, front radiator. Oh ...ok...Porsche ..
|starting with the Boxster ....that's Porshce's first waterboxer engine...
|and they had problems with that engine right away ...oil in the coolant or
|something like that.
|Those theoretical engineers ....
|if I was in charge ...after the engineers designed it to be good enough ...
|strong enough , cost-effective enough, etc.....I'd demand they make it 20 %
|better yet....because 'theoretically enough' in the real world often does
|not cut it really.
|
|And yet ...vanagons are just fantastic vehicles, with their special needs
|for sure, but worth it.
|and I can change entire engines and not bleed fanatically to the front, and
|things are just fine.
|
|and any time much bleeding is needed, something else is likely wrong, and
|the mind goes to 'head gaskets' at that point.
|The head gaskets are good for about 5 to maybe 8 years max.
|the little green o-ring that keeps coolant away from the metal rings at the
|top of the barrels...those get hard and cruddy in just a few years
|sometimes.. It can't really work that well really long term. But we love
|'em
|anyway !
|
|and if one is to be bothered by anything in Vanagon waterboxer cooling
|systems...
|it would be the silly head gasket set up.  It 'can't' really work long
|term.
| Getting one of the 3 failure modes is not that uncommon - in the
|heads/head
|gaskets :
|It's either external leaks at the rubber outer gasekts,. coolant being used
|through the engine, or exhaiut getting into the coolant part of the
|engine.,
|But we do love them anyway, and we manage to live with it. And that's
|partially why we all know each other here. If they never needed any work ,
|we might not be here together.
|
|
|
|
|From: "Tobias Gogolin" <usertogo@GMAIL.COM>
|To: <vanagon@GERRY.VANAGON.COM>
|Sent: Thursday, April 22, 2010 12:13 AM
|Subject: Re: Water Cooler System Design Flaw Workaround?
|
|
|> Yes, as Industrial designer and even more as just a German I am deeply
|> disturbed by the thought that something so imperfect could have gone into
|> production...
|>
|> I'm thinking about replacing the purging screw on the radiator in front
|> with
|> a Hose nipple and some kind of automatic purging scheme?
|>
|>
|>
|> On Thu, Apr 22, 2010 at 12:03 AM, Tom Hargrave <thargrav@hiwaay.net>
|> wrote:
|>
|>> Tobias,
|>>
|>> Air in the cooling system will cause problems regardless of the vehicle
|>> and
|>> air blocking coolant flow, not lack of coolant is what causes most
|>> engines
|>> to overheat. The water pump can't overcome bubble in the upper radiator
|>> hose
|>> when you stop and your temperature spikes.
|>>
|>> But several European cars have what I consider a flaw in the cooling
|>> system
|>> - the "flaw" is that the designers route the upper radiator hose so high
|>> or
|>> mount the radiator so low that the system can't self purge. This "flaw"
|>> requires you to purge the system after any coolant service. For example,
|>> you
|>> WILL DESTROY THE ENGINE in some 3 series BMWs if you don't follow the
|>> correct bleeding procedure to purge the air bubble out of the upper
|>> radiator
|>> hose after performing a coolant service. I'm sure the if the vanagon has
|>> the
|>> same flaw then it has a similar purge procedure and someone else more
|>> knowledgeable than me of vanagon cooling systems can give you
|>> instructions.
|>>
|>> No reflection on your abilities but this is a good example of home
|>> mechanics
|>> or pro mechanics without the right experience doing more harm than good
|>> because they know just enough about what they are working on to get into
|>> trouble. The mechanic would change the coolant, not properly purge the
|>> system and then the mechanic or his customer would pay the consequences
|>> later.
|>>
|>> Tom
|>> www.kegkits.com
|>>
|>>
|>> -----Original Message-----
|>> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
|>> Of
|>> Tobias Gogolin
|>> Sent: Wednesday, April 21, 2010 11:56 PM
|>> To: vanagon@GERRY.VANAGON.COM
|>> Subject: Water Cooler System Design Flaw Workaround?
|>>
|>> I suppose most of us are aware that if for whatever reason there is air
|>> in
|>> the cooling system of a Vanagon (T3?) it will overheat because the
|system
|>> gets 'air locked'. That means the coolant cant flow through the radiator
|>> because it would have to push air down in the return path an there is
|>> obviously not enough pressure to do that...
|>> I'm suspecting there could be some solution, one would be to put the
|>> radiator down where the spare tire is and eliminate the potential vapor
|>> lock, or... what else ?
|>>
|>> Thanks!
|>>
|>> Tobias
|>>
|>>
|>
|>
|> --
|> Tobias Gogolin
|> Tel. Movistar (646) 124 32 82
|> Tel. Telcel (646) 160 58 99
|> skype: moontogo
|> messenger: usertogo@hotmail.com
|>
|> Blog: http://zeitgeistensenada.blogspot.com/
|>
|> You develop Sustainable Ranch Technology at
|> http://tech.groups.yahoo.com/group/SURA-TECH
|> an Open Source Electric Motor/Alternator at
|> http://groups.yahoo.com/group/Performance_Axial_Flux
|> and an Open Source Motor Controller at
|http://groups.yahoo.com/group/GoBox