Date:         Tue, 26 May 2009 17:06:02 -0230
Reply-To:     Joy Hecht <jhecht@ALUM.MIT.EDU>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Joy Hecht <jhecht@ALUM.MIT.EDU>
Subject:      Re: AMC valves, Boston Bob
In-Reply-To:  <2f18aa9f0905261233v6ae1df01me47c1d3b516c052e@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

It's strange to see Bob's name in the subject line when he's no longer out
there to talk to us.

I miss you, Bob!  I hope you're still reading our emails, wherever you've
gone to.



Joy



On Tue, May 26, 2009 at 5:03 PM, VW Doka <vw.doka@gmail.com> wrote:

> Unfortunately, I've had the opposite experience.  At least 50% of the
> AMC heads I've removed from WBX'er engines have had damaged valve
> stems at the keepers.  Some have been really bad, others just a little
> loose.
>
> I'm guessing about 25 to 30 sets of AMC heads over the past 10 years.
>
> We never leave the original exhaust valves in AMC heads when we
> rebuild an engine.  Just not worth the risk.
>
> Just my experience...
>
> Cheers,
>
> Jeff
>
>
>
> On Tue, May 26, 2009 at 3:18 PM, Ken Wilford <kenwilfy@comcast.net> wrote:
> > I spent a bunch of time on the phone with Bob talking about this subject
> > as well, but I believe all of this fear and loathing about the AMC
> > valves is due to a bad batch of these heads back about 6 or 7 years
> > ago.  I have never had a failure like the one Bob always warned me about
> > and I never changed the valves from the stock ones.  Recently I had a
> > pair of AMC heads that I installed on an engine about two years ago come
> > back into my possession (engine threw a rod).  The heads had about 18k
> > miles on them.  I took the heads to a machine shop to have them checked
> > and a valve job done before selling the heads to a list member.  I asked
> > the machine shop about the condition of the valve keepers, grooves on
> > the valve stems, etc.  He said that he had inspected them and they were
> > like new condition and that they valves themselves were also in like new
> > condition.  I can say that I have never had an AMC head fail in 11 years
> > of installing them.  I have never had one that I have sold to a customer
> > fail due to a bad valve either.  Anything can fail if you abuse it, or
> > improperly install it, or don't correctly adjust the valves, etc.
> > However I have never found the stock AMC valves to have any issues.  If
> > you want to spend extra money on "better" valves and install them only
> > to have them fail (I have known this to happen) that is your choice.
> > However the stigma against using the AMC heads out of the box is totally
> > unfounded as far as I am concerned.
> >
> > Just my experience,
> > Ken Wilford
> > John 3:16
> > www.vanagain.com
> >
> >
> > Zoltan wrote:
> >>
> >> One important fact I learned from Bob, was that the AMC heads have loose
> >> keepers.  The two halves meet each other to touch, thus grabbing the
> valve
> >> stem, being loose, they travel up and down until they break through the
> >> grooves and the valve free to move deeper inside and then operated by
> the
> >> piston to have it pushed up.
> >> So, the first thing I recomment to anyone I meet is to have the keepers
> >> ground at their sides until they don't touch each other.
> >> Bob was very happy with the AMC heads and tossed the old ones for their
> >> metal fatigue.  In his experience, it was not worth chancing all the
> >> troubles by putting the old ones back.
> >> He liked the better material the AMC heads are made of.
> >> So, the keepers must be fixed first.
> >> Zoltan
> >>
> >>
> >
>