Date: Tue, 11 Apr 2023 18:01:36 -0400
Reply-To: John T <john.thiessen@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John T <john.thiessen@GMAIL.COM>
Subject: Re: When & why replace heads? A Friday Dennis Discussion.
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Dennis, I'm curious about your comment regarding the "effect on the
transmissions, especially the automatics".
Last year I acquired an 85 with a stock automatic transmission (with
external cooler) and a Subi 2.2. As a former 10+ year air-cooled Vanagon
driver, if I drive this new configuration like an air-cooled, and
therefore not subject the automatic transmission to the increased torque,
what longevity concerns might I face?
John
On Sun, Apr 9, 2023 at 10:03 AM Dennis Haynes <d23haynes57@hotmail.com>
wrote:
> Happy Easter and the coming of Spring.
> From experience the Subie 2.5is amongst my favorite. While I have seen
> some issues with the few I have worked on the major downside is the effect
> on the transmissions, especially the automatics. Here is NY we also have to
> consider the issue of getting caught. While we don’t have regular
> enforcement (95 and older do not get scheduled emissions inspections) we
> other wise follow the CARB. As an added twist to prevent someone placing a
> non OBDII engine into an OBDII engines 93 and later are also regulated.
> AFAIK no one has yet had a Subie 2.5 certified or an approved exemption for
> the Vanagon. With the number of suppliers offering this setup maybe some
> day the investment will be made.
>
> For the Waterboxer, there are still many of them running with original
> engines in place, even with some repairs. The engine in Fun Bus has
> outlasted 3 transmissions and at this point the chassis. The mount for the
> right rear trailing arm is failing so the van is off the road waiting for
> some major welding repair. For my 91 the heads were replaced at 168K. At
> 248K the exhaust valve for cylinder #2 burned. I pulled the heads,
> replaced the one valve, removed the liners and replaced the rings. Now at
> 297K and running strong. Usage has dropped since I acquired a Denali Crew
> last May. But even with the flywheel leak this engine doesn't burn oil and
> has made numerous NY to Florida trips. The final drive for the transmission
> is in need of replacement as the pinion bearings are loose so I know the
> housing is shot. That trans is also original except for the parking paul
> getting busted and the torque converter. Yes they do fail.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List <vanagon@gerry.vanagon.com> On Behalf Of John
> Rodgers
> Sent: Friday, April 7, 2023 11:45 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: When & why replace heads? A Friday Dennis Discussion.
>
> Dennis and all.
> The many reasons, Dennis, you listed is why I FINALLY opted for the Subaru
> engine. I put a completely rebuilt 2005 2.5 L engine in my '91 CARAT. I got
> desparately tired of the troubles the 2.1 L wasserboxer was causing and the
> continuing cost of repairs. I am so very glad I did. For the most part
> trouble free operation, plenty of power, and better gas mileage. BUT I am
> keenly aware of the fact these engines can give trouble also. They are not
> perfect, but I find them better than the old WBX. The big plus is that this
> is a modern design, modern metallurgy, modern electronics, and parts are
> plentiful. I am enjoying the heck out of mine.
>
> On Fri, Apr 7, 2023 at 6:33 PM Dennis Haynes <d23haynes57@hotmail.com>
> wrote:
>
> > For many engines the cylinder heads and the sealing of the heads to
> > the block tend to be the first thing to require service. The Vanagon
> > adds an additional "dimension" to the opportunity for failure due to
> > the method of sealing at the top of cylinders and then the outer
> > gasket sealing the water jacket.
> >
> > As for removing the heads for repair or replacing them that is part of
> > a diagnostic and inspection process. The only reason that the heads
> > would really need to be replaced is if they are damaged or cracked.
> > Fortunately Waterboxer heads are available and relatively cheap. For
> > most engines heads get repaired including welding and machine work and
> > there used to be machine shops in many parts stores that provided
> > those services. At current labor rates even a simple valve seat grind
> > and valve replacement will quickly exceed the cost of anew head,
> > especially if the guides also need to be done.
> >
> > So lets look at the most common problems with the Waterboxer heads.
> > Probably the most common is leaking at the outer water jacket gasket.
> > Next is failure of the seal between the heads and the top of the
> cylinder(s).
> >
> > For the outer water jacket gasket leaking or failing, this is always
> > due to the gasket and/or the sealant failing. The failure could be
> > just a failure of the sealant causing a minor drip or the gasket
> > actually spitting and allowing for a near instant dump of coolant.
> > Failures can also happen quickly after a replacement due to inconstant
> > dimensions of the gasket, the case, head, and yes the cylinder barrels
> > or the base of the bores that the cylinder barrels sit on. I have had
> > this gasket fail and embarrass me on a number of occasions.
> >
> > For the sudden failure splitting over time, this is usually the result
> > of the gasket seal having a slow leak. Which will then cause the head
> > to corrode under the gasket. This corrosion will grow and eventually
> > penetrate the gasket forcing it to split on the flat surface. Sudden
> coolant loss.
> > This event is a trauma to the engine and can cause a lot of damage
> quickly.
> > Warped and cracked heads along with tweaking the head studs. If the
> > outer gasket is the only concern, if the head can be pulled without
> > disturbing the cylinders it is common to pull the head(s), clean the
> > surfaces, also clean the groove sand replace the o-rings on top of the
> > cylinders, new gaskets, with proper installation and torquing the
> > heads may be all the is needed to set things right.
> >
> > For the top of cylinder to head seals the usual symptom is in-ability
> > to keep the cooling system free of air and coolant being pushed out
> > when engine is heated and underload. Sometimes this is illusive only
> > happening after some extended driving period. This failure is almost
> > always due to the studs losing tension which can happen for a number
> > of reasons. Also, if the cylinders are not perectly square and level
> > as a set, you won’t get a good seal up there. This can be caused by
> > miss matched or out of spec cylinders or a worn, damaged, warped
> > engine case. If the cylinders are parallel but just a different height
> > different thickness gaskets may be used at the top of the barrels to
> > compensate. You will need to make or have made custom gaskets from
> copper sheet.
> >
> > One needs to consider that as part of removing the heads things can
> > quickly go wrong or be found that will move the job to engine
> replacement.
> > You need to be prepared for this possibility for both the time and money.
> > Keep in mind that for as much this engine can accept some repairs like
> > may automotive engines it is designed as a throw away. Going back to
> > even the beetle days these alloy based engines supplied as dealer
> > supplied factory rebuilds almost always had a brand new case. Rebuilt
> > heads and most internals, but always a new case. Many problems will
> > come back to a bad case.
> >
> > Dennis
> >
> >
> >
> > -----Original Message-----
> > From: Vanagon Mailing List <vanagon@gerry.vanagon.com> On Behalf Of
> > Dan N
> > Sent: Friday, April 7, 2023 6:11 PM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Re: When & why replace heads?
> >
> > *"My question is what are the main reasons for replacing heads and how
> > do you know when you've reached that point?"*
> >
> > Compression test and leak down test? - The rings and cylinder walls
> > may still be good but the valves and valve seats are worn...
> >
> > On Fri, Apr 7, 2023 at 3:01 PM David McNeely <davmcneely40@gmail.com>
> > wrote:
> >
> > > Very ignorant here, but my feeling is leaking heads mean it's time
> > > to do the job. Do you want the engine to blow up when moving at
> > > high speed (or any time for that matter)?
> > >
> > > On Fri, Apr 7, 2023 at 6:45 AM Spencer Allen
> > > <soxndubs1951@gmail.com>
> > > wrote:
> > >
> > > > I had my 85 stock westy inspected and some brake work done and the
> > > mechanic
> > > > says I should replace the leaking heads. I may have jumped the gun
> > > > and ordered the GW super duper ($$$) reworked AMC heads. The thing
> > > > is my OE heads have been leaking for the last 20 years and 60K
> > > > I've owned it. The major leaking occurs during the winters while
> > > > it's stored in my garage so when spring comes I have to top up the
> > > > fill tank with about a qt of coolant. Summer it does drip but
> > > > nothing major. Engine runs fine with no white exhaust smoke. My
> > > > question is what are the main reasons for
> > > replacing
> > > > heads and how do you know when you've reached that point?
> > > > Spencer
> > > >
> > >
> >
>
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