Date: Thu, 9 May 2013 21:36:34 -0700
Reply-To: Stuart MacMillan <stuartmacm@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stuart MacMillan <stuartmacm@GMAIL.COM>
Subject: Re: coolant overflow fears and thoughts
In-Reply-To: <BAY152-ds86574FC5C2EFE4A841261A0A50@phx.gbl>
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Dennis, I hope you hit 300k and beyond! Toyota once did commercials
featuring owners that hit this milestone, but unfortunately that's not an
option for you or any of us with Volkswagen. ;-)
As you point out, I've always believed the case is a wear item. It's the
metallurgy of titanium/aluminum alloys--they will harden and get brittle
with heat and mechanical pounding over time. It's essentially the same
"forging" that hardens any metal, and they get pounded hard in a three main
bearing engine.
As you know the early aircooleds pulled studs in normal use, and case stud
inserts were standard with a rebuild. "Align boring" of the case was also
standard due to the crank pounding out the case journals. With the later
aircooleds and their WBX derivatives the metallurgy was improved to delay
these problems, but the case does have a finite lifetime, which is why I
believe a conversion to a modern engine is the preferred long term solution.
I abandoned the 1.9 in my '84 van after 200k just because I thought it was
done even though it was running fine, but I think it would have gone a lot
farther.
Stuart
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Dennis Haynes
Sent: Thursday, May 09, 2013 8:34 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: coolant overflow fears and thoughts
Fun Bus has almost 256K on the original engine. Heads have never been off. I
have been using it as a daily driver again for the past three weeks testing
it for summer after it sat for over two years getting painted. I can feel
that the transmission has a cracked 3-4 slider hub, (again). I just replaced
the front exhaust pipe and the heads are starting to crumble on the outside.
As for driving the flat east coast this van been across country twice
including a trip to Alaska in 1993. Made it all the way up Prudhoe bay and
it turned 100K on the Alaska Highway between Anchorage and Denali. Over the
years I have found that the real problem with the water boxer is the support
systems. Almost all engine failures are the result of past cooling system
issues or other outside influences damaging the engines. As for rebuilds not
lasting as they should part of it is replacement part quality, incorrect
assembly, or re-using consumable parts without the proper machine work or
they are just done. Unfortunately the case is a wear item. The factory
rebuilds almost always had a new case. Machined and welded heads with over
size valve guides, yes, reground cranks, sometimes just the rod journals,
not the mains, reused cylinders, re ground and hardened cams, metal sprayed
and reground flywheels, yep seen it all but almost always a new case. There
was a reason. The other problem I find is that the cuase of the original
engine failure is often not found or corrected until that problem has also
damaged the replacement engine.
Fun Bus does run Mobil 1, 15w-50 and usually 7,500 mile change intervals. I
also have a very effective oil cooler system on it. When on trips I drive it
somewhat hard. Depending on traffic I'll run it 65-75 mph stopping for fuel
and potty. The engine still maintains proper oil pressure.
While the head gasket design is not the best the engine itself is very well
suited to being operated at the upper limits just like most truck engines
are operated. The piston design and floating cylinder sleeves make for an
engine that can dissipate heat, be pre-ignition (ping) resistant and operate
under a sustained load for long periods. It is not super-efficient or
powerful but it will get the job done.
Dennis