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What makes AMC heads so great then if the the valves need to be replaced?� Is this recommended in the sales brochure by the Andalusian Matadors Confederation?
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Robert
1982 Westfalia
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--- On Wed, 5/27/09, Jerry <jbvelo@BELLSOUTH.NET> wrote:

From: Jerry <jbvelo@BELLSOUTH.NET>
Subject: Re: AMC valves, Boston Bob
To: vanagon@GERRY.VANAGON.COM
Date: Wednesday, May 27, 2009, 6:43 PM

There are different processes for completing
a correct valve/head job.� I personally would
never trust the valve work from other than a
reputable mechanic.� If I were to order the AMC
heads from a vendor without knowledge of their
technique or abilities, I would make sure that
very good quality valves are used. This would
mean total disassembly of the heads, replacing
the valves, checking spring tension, etc.

I do know that Bob Donalds guaranteed his
AMC heads.� He replaced the AMC valves with
OEM valves.� He also checked spring height
and tension.� I had a long discussion with
Bob in March 2008 about his method of completing
valve work.� The best method of doing a valve
job is known as "interference angle".� The valve
seat angle may be 45 degrees.� When you do
interference angle you would grind the valve face
at 44 degrees.� This method ensures a positive
seating angle for the valve face. The other important factor
is the valve seating width. Normally you want
the valve seating width to be around 1/16 ".
And you want the valve seat to be in the middle of the
valve face.� You obtain this valve seat dimension
and width using three different stones (interference angle).
You use a 60 degree stone to widen the throat
area. This will move the seating position toward
the outside of the valve face.� You use a 15 degree
stone on the top of the valve seat to move the
seating area to the inside of the valve face.

So, your optimal valve sealing area is approximately
1/16" in the middle of the valve face.� The valve sealing
area needs to be narrow so there is a good, effective seal.
The sealing area also needs to be wide enough to transfer
heat and provide cooling for the valve head.

Bob took time to do a valve job the correct way.
I don't know about other people but Bob Donalds
knew what he was doing.

I did valve jobs on diesel engines and I always
used the "interference angle" method.� It's the only
way to correctly complete a valve job and have confidence
that the valves are sealing they way they should.

Bob also identified problems with AMC valves and
the valve keepers.� You damn sure don't want a
valve dropping at 4000 RPM because of a bad keeper
or valve stem.

JB 88 GL KY

On 5/27/09 1:03 PM, "Marc Perdue" <mcperdue@GMAIL.COM> wrote:

> Given the widely diverse experiences you all are having/have had, I'm
> beginning to wonder if there's a difference in your processes, i.e.,
> what exactly you do when you replace the heads, set the valves, what
> specs things are set to, etc.� On the surface of it, you'd think there
> couldn't be a difference; after all, how many ways are there to do the
> job?� However, all other things being equal, i.e., if the AMC heads
> each of you get are essentially identical, then how is it you could be
> getting such different results?� This is just sort of the systems
> analyst in me talking, with a hypothetical ponderance...
> Environmental considerations certainly could come into play, I
> suppose, but I suspect there's something else going on . . .
> 
> Marc
> 
> On Wed, May 27, 2009 at 1:51 PM, VW Doka <vw.doka@gmail.com> wrote:
>> "Doesn't exist"?? �That pile of scrap AMC heads that I took the
>> recycler must've been a mirage...
>> 
>> Perhaps it's a "west coast" thing...
>> 
>> Jeff
>> 
>> 
>> 
>> On Wed, May 27, 2009 at 10:37 AM, Ken Wilford <kenwilfy@comcast.net> wrote:
>>> Jake, I am with you on this one. �I have done many, many head gasket
>>> replacements and head replacements over the years. �I don't know the
>>> exact number but it is well over 50 at this point (maybe over 100 I
>>> don't know). �I have used the AMC heads exclusively for the past 11
>>> years. �Out of all of those jobs I have never had one come back due to a
>>> bad valve. �Actually out of all of those jobs I have only ever had to
>>> redo one and that was at the very beginning of my business and due to a
>>> bad spot on the case that I didn't properly address (live and learn).
>>> Beside that I have never had a head gasket or head replacement job ever
>>> come back or have a problem that I know of. �That is a pretty good track
>>> record. �I am a small shop, I hate returns way worse that you ever could
>>> since I do this job many times a year not just once. �If I thought for a
>>> moment that this was a problem I would change the valves myself so that
>>> I could avoid a come back. �It just has never happened so I don't feel
>>> like treating a disease that doesn't exist. �I am just sharing my
>>> experience here.
>>> 
>>> Ken Wilford
>>> John 3:16
>>> www.vanagain.com
>>> 
>>> 
>>> Jake de Villiers wrote:
>>>> 
>>>> I'm with Jeff. �If an 'improved' head with better valves and tweaked
>>>> keepers
>>>> is only $100 more than an AMC head that is good for ~30,000 miles, why
>>>> would
>>>> I want to cheap out?
>>>> 
>>>> The labour to re & re the head that swallowed a valve will be at least
>>>> $1000, you and they'll want to check the other side too that's $2000 plus
>>>> towing etc.
>>>> 
>>>> Why wouldn't you want to do it right the first time? �I know which shop
>>>> I'd
>>>> get my heads replaced at - the one that does the best job *ONCE*!
>>>> 
>>>> On Tue, May 26, 2009 at 3:17 PM, Jeff <vw.doka@gmail.com> wrote:
>>>> 
>>>> 
>>>>> Ken,
>>>>> 
>>>>> Actually, the wholesale cost of a bare (no valves, springs or keepers)
>>>>> AMC
>>>>> head is substantially below $300, so a $499 "upgraded" head is easily
>>>>> doable.
>>>>> 
>>>>> Even the wholesale cost of a complete AMC head is below your example
>>>>> below
>>>>> of $389.
>>>>> 
>>>>> As for valves... wholesale cost of "better" exhaust valves is less than
>>>>> $25,
>>>>> intakes are less than $10. �When I say "better", I'm referring to TRW
>>>>> valves
>>>>> that are made in Germany.
>>>>> 
>>>>> And these are my prices. �A large company that purchases in bulk will get
>>>>> much better pricing.
>>>>> 
>>>>> 
>>>>> One thing that we commonly do is to reuse the original VW valves (if they
>>>>> are within specifications) on new AMC heads.
>>>>> 
>>>>> 
>>>>> Cheers,
>>>>> 
>>>>> Jeff
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> -----Original Message-----
>>>>> From: Ken Wilford [mailto:kenwilfy@comcast.net]
>>>>> Sent: Tuesday, May 26, 2009 5:32 PM
>>>>> To: VW Doka
>>>>> Cc: vanagon@GERRY.VANAGON.COM
>>>>> Subject: Re: AMC valves, Boston Bob
>>>>> 
>>>>> Jeff,
>>>>> OK, let's pretend that you are going to replace your exhaust valves with
>>>>> "better" ones that are around $35 each. �This is just exhaust valves
>>>>> however there are two of these per head ($70) then you are going to want
>>>>> to use "better" intake valves which run around $20 each ($40 per head).
>>>>> So just in valves you are talking about adding $110 in cost per head.
>>>>> Now look at what folks are charging for the heads with the "better"
>>>>> valves. �A certain company who shall remain nameless is selling their
>>>>> "better" valve heads for $499 each. �This would mean that they would
>>>>> have to buy their heads at $389 each just to break even (not making any
>>>>> money and not factoring in their labor). �The heads just aren't this
>>>>> cheap. �Even if they could get the heads for $300 (way below what anyone
>>>>> can actually get them for wholesale) you are talking about only making
>>>>> $89 per head which wouldn't be worth it. �That might cover your labor in
>>>>> removing, installing and lapping the valves but that is it. �No profit.
>>>>> The math just doesn't work. �The only way it works out is if you take
>>>>> the AMC valves out and put something else in that is relatively cheap.
>>>>> I know one particular rebuilder who shall remain nameless who was
>>>>> replacing the AMC valves with aftermarket stainless ones that he could
>>>>> get pretty cheaply. �This was working well for him for a while until he
>>>>> ran into a bad batch of these aftermarket valves that had improperly
>>>>> heat treated stems and had valves start failing on him. �So the very
>>>>> "problem" that he was supposed to be fixing by replacing the valves was
>>>>> the thing that started happening. �Ironic, isn't it?
>>>>> 
>>>>> So if people wanted to pay a premium for heads with OE valves installed
>>>>> I would have no problem with that. �People can pay a premium to get
>>>>> premium valves. �However when a company says their heads are better when
>>>>> they are putting in aftermarket valves which may or may not be any
>>>>> better than what they are replacing I just don't think this is right.
>>>>> Just my opinion.
>>>>> 
>>>>> Ken Wilford
>>>>> John 3:16
>>>>> www.vanagain.com
>>>>> 
>>>>> VW Doka wrote:
>>>>> 
>>>>>>> From my experience, they start to show significant valve stem wear
>>>>>> around 20k miles. �Failure around 40k miles.
>>>>>> 
>>>>>> The bad batch story is just that... a story. �The AMC heads sold today
>>>>>> still use the same cheap, crappy exhaust valves as the ones from 5
>>>>>> years ago. �You can buy the same valves brand new for about $7. �A
>>>>>> good exhaust valve for the WBXer runs about $35.
>>>>>> 
>>>>>> Not conjecture, not really opinion... just my experience.
>>>>>> 
>>>>>> Cheers,
>>>>>> 
>>>>>> Jeff
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> On Tue, May 26, 2009 at 4:13 PM, Robert Keezer <warmerwagen@yahoo.com>
>>>>>> 
>>>>> wrote:
>>>>> 
>>>>>>> Very logical . After all, how would a company like this stay in
>>>>>>> business
>>>>>>> 
>>>>> year after year with notoriously bad valves?
>>>>> 
>>>>>>> �It just did'nt make sense.
>>>>>>> 
>>>>>>> I think Kens' answer is reasonable fro me to go by.
>>>>>>> 
>>>>>>> One bad batch has perpetuated this myth all these years. I �never
>>>>>>> 
>>>>> believed it .
>>>>> 
>>>>>>> Most of my Vanagons sold with AMC heads and never a complaint.
>>>>>>> Which is why I asked, how long do they last? This bad batch head?
>>>>>>> 
>>>>>>> If they went bad in 5 years, I would'nt expect to hear from the buyer .
>>>>>>> One year or less maybe . Less than 6 months probably.
>>>>>>> 
>>>>>>> Robert
>>>>>>> 1982 Westfalia
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> --- On Tue, 5/26/09, Ken Wilford <kenwilfy@COMCAST.NET> wrote:
>>>>>>> 
>>>>>>> 
>>>>>>> From: Ken Wilford <kenwilfy@COMCAST.NET>
>>>>>>> Subject: Re: AMC valves, Boston Bob
>>>>>>> To: vanagon@GERRY.VANAGON.COM
>>>>>>> Date: Tuesday, May 26, 2009, 12:18 PM
>>>>>>> 
>>>>>>> 
>>>>>>> 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
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>> 
>>>> 
>>>> 
>>>> 
>>>> --
>>>> Jake
>>>> 
>>>> 1984 Vanagon GL
>>>> 1986 Westy Weekender "Dixie"
>>>> 
>>>> Crescent Beach, BC
>>>> 
>>>> www.thebassspa.com
>>>> www.crescentbeachguitar.com
>>>> http://subyjake.googlepages.com/mydixiedarlin%27
>>>> 
>>>> 
>>> 
>>