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Re: [Healeys] valve guides

To: Austin Healey <pajtamuvek@gmail.com>
Subject: Re: [Healeys] valve guides
From: Michael Salter <michaelsalter@gmail.com>
Date: Sun, 29 Mar 2015 10:49:06 -0400
Cc: "healeys@autox.team.net" <healeys@autox.team.net>
Delivered-to: mharc@autox.team.net
Delivered-to: healeys@autox.team.net
References: <11845844.18350440.1427480243323.JavaMail.root@shaw.ca> <CAB3i7LKpx2C-QkV6Nedp2QdPLjJn7fBEG+k6LJDiZVKGnuiVmw@mail.gmail.com> <CA+QDXmAcZJJ+oWZREp6wTF8eR0pd51bfsDKmJEacs5vFUz2taw@mail.gmail.com> <CAB3i7LKC+dUV3n7YfMLSEuX1_NAp5Y6e3qy6BXawkGVGJDkQwg@mail.gmail.com> <CA+QDXmAq4ZJz0fxZ8pbJToLNWGLVTSzM4XB1DG2q7Jja0E1c_w@mail.gmail.com> <CAB3i7LK1RXLoKhTegO+1YJafamL6NZd4DCfWc2KUsAtpAHOxOw@mail.gmail.com> <CA+QDXmAgQZWwD7NFd8b9fEUkrQ0z6XRC+EeAusAMwHvm_6kdgA@mail.gmail.com>
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--089e01227acea6f3e905126e7730

Ok Gergo,
We are making progress....
>From your answer I believe that you would concur that both the ID and the
OD of an unrestrained guide would increase as it is heated . i.e. thermal
expansion.
However, you conclude that solids are, to quote, "not that "solid" as they
may look".
>From that statement I presume that you are indicating that the solid
material of the guide distorts or deforms because it is constrained by the
hole in the cylinder head.
Now I would ask you to refer to this video from Purdue University College
of Technology:
https://www.youtube.com/watch?v=V6D3QgdO5Bk
If you are not into the mathematics just skip to 6:45 for the result.
371,000 lbs (168tonnes)!!!
Now check the structural strength of bronze... of course it varies a little
with different alloys but a yield strength of 650 Mpa ( 94274 p.s.i.) is
typical.
The mathematics required to use these numbers to calculate the forces
required to radially crush a cylinder (i.e. our valve guide)  are a little
complex but be assured the numbers are MASSIVE.
So, if the wall of our guide is presumed to have an area of only 600 sq mm.
(0.1 sq in), it would take 4276 kg (9427lbf)to distort or deform it.
Now, armed with that knowledge please read my blog post
<http://www.netbug.net/blogmichael/?p=384> carefully and you may have an
inkling for why I strongly advise against the use of bronze guides in a
cast iron head.

Michael S






On Sun, Mar 29, 2015 at 3:25 AM, Austin Healey <pajtamuvek@gmail.com> wrote:

> Yes. This is happening. The head material expands less, the guide expand
> more, and thus it has to go somewhere. Metals are not that "solid" as they
> might look like.
>
> Gergo
>
> 2015-03-29 4:09 GMT+02:00 Michael Salter <michaelsalter@gmail.com>:
>
>> So Gergo,
>> if I understand you correctly in a situation where the guide was not
>> installed in a head and it was then heated the outside diameter and for
>> that matter the inside diameter of the guide would increase due to thermal
>> expansion....correct?
>> However, the difference, when the guide is installed in the head is that
>> the head material, i.e. the hole that the guide is installed in, would
>> prevent the guide from expanding or, expressed another way, because the
>> hole in the head would not increase in diameter as much as the guide would
>> increase in diameter the head material would effectively compress the guide
>> and prevent it from expanding..... correct?
>>
>> Michael S
>>
>> On Sat, Mar 28, 2015 at 4:38 PM, Austin Healey <pajtamuvek@gmail.com>
>> wrote:
>>
>>> Yes it does. The material has to expand somewhere. It cant go in the
>>> oposite direction.
>>>
>>> g
>>>
>>> 2015-03-28 20:12 GMT+01:00 Michael Salter <michaelsalter@gmail.com>:
>>>
>>>> Hi Gergo,
>>>> just so I'm clear...you are suggesting that the internal diameter of
>>>> the guide will get smaller as it heats up therefore that extra clearance is
>>>> required?
>>>> Michael S
>>>>
>>>> On Sat, Mar 28, 2015 at 3:08 AM, Austin Healey <pajtamuvek@gmail.com>
>>>> wrote:
>>>>
>>>>> Bronze guides expand more when they heat up. Thats why You have to use
>>>>> greater clearance. But when they work, the clearance will be the same. 
>>>>> Worn
>>>>> out guides have two negative side effects: oil consumption, and premature
>>>>> wear on the valves as they dissipate heat slower due to rocking on the
>>>>> valve seat. The exhaust guides are more prone to oil consumption, exhaust
>>>>> guides are more prone to overheating.
>>>>>
>>>>> Gergo
>>>>>
>>>>> 2015-03-27 20:01 GMT+01:00 Michael Salter <michaelsalter@gmail.com>:
>>>>>
>>>>>> Hi Raymond,
>>>>>> The factory specification calls for 0.0025 to 0.0015 clearance for
>>>>>> the inlets and 0.002 to 0.001 clearance for the exhausts if you are using
>>>>>> cast iron guides however if you are using bronze THAT WILL NOT WORK!!!
>>>>>> To be safe with bronze guides you will have to hog them out to about
>>>>>> 0.006" clearance..which means there is really no point in replacing them.
>>>>>> I would point you to this article
>>>>>> <http://www.netbug.net/blogmichael/?p=384> on my blog...been there
>>>>>> done that...
>>>>>>
>>>>>> Michael S
>>>>>> BN1 #174
>>>>>>
>>>>>> On Fri, Mar 27, 2015 at 2:17 PM, RAYMOND SMITHSON <rjsmithson@shaw.ca
>>>>>> > wrote:
>>>>>>
>>>>>>> I am rebuilding my 3000 cylinder head and have found the inlet valve
>>>>>>> stems have .008" clearance but the exhaust stems have only .002" 
>>>>>>> clearance.
>>>>>>> Does anyone know if this is common?
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Support Team.Net http://www.team.net/donate.html
>>>>>>> Suggested annual donation  $12.75
>>>>>>> Archive: http://www.team.net/archive
>>>>>>> Forums: http://www.team.net/forums
>>>>>>>
>>>>>>> Healeys@autox.team.net
>>>>>>> http://autox.team.net/mailman/listinfo/healeys
>>>>>>>
>>>>>>> Unsubscribe/Manage:
>>>>>>> http://autox.team.net/mailman/options/healeys/michaelsalter@gmail.com
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> *If you can't fix it with a hammer, you've got an electrical problem.*
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Support Team.Net http://www.team.net/donate.html
>>>>>> Suggested annual donation  $12.75
>>>>>> Archive: http://www.team.net/archive
>>>>>> Forums: http://www.team.net/forums
>>>>>>
>>>>>> Healeys@autox.team.net
>>>>>> http://autox.team.net/mailman/listinfo/healeys
>>>>>>
>>>>>> Unsubscribe/Manage:
>>>>>> http://autox.team.net/mailman/options/healeys/pajtamuvek@gmail.com
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> *If you can't fix it with a hammer, you've got an electrical problem.*
>>>>
>>>>
>>>
>>
>>
>> --
>> *If you can't fix it with a hammer, you've got an electrical problem.*
>>
>>
>


-- 
*If you can't fix it with a hammer, you've got an electrical problem.*

--089e01227acea6f3e905126e7730
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div class=3D"gmail_default" style=3D"font-family:comic sa=
ns ms,sans-serif;font-size:small">Ok Gergo, <br></div><div class=3D"gmail_d=
efault" style=3D"font-family:comic sans ms,sans-serif;font-size:small">We a=
re making progress....<br></div><div class=3D"gmail_default" style=3D"font-=
family:comic sans ms,sans-serif;font-size:small">From your answer I believe=
 that you would concur that both the ID and the OD of an unrestrained guide=
 would increase as it is heated . i.e. thermal expansion.<br></div><div cla=
ss=3D"gmail_default" style=3D"font-family:comic sans ms,sans-serif;font-siz=
e:small">However, you conclude that solids are, to quote, &quot;not that &q=
uot;solid&quot; as they may look&quot;. <br></div><div class=3D"gmail_defau=
lt" style=3D"font-family:comic sans ms,sans-serif;font-size:small">From tha=
t statement I presume that you are indicating that the solid material of th=
e guide distorts or deforms because it is constrained by the hole in the cy=
linder head.<br></div><div class=3D"gmail_default" style=3D"font-family:com=
ic sans ms,sans-serif;font-size:small">Now I would ask you to refer to this=
 video from=C2=A0Purdue University College of Technology: <br><a href=3D"ht=
tps://www.youtube.com/watch?v=3DV6D3QgdO5Bk">https://www.youtube.com/watch?=
v=3DV6D3QgdO5Bk</a><br></div><div class=3D"gmail_default" style=3D"font-fam=
ily:comic sans ms,sans-serif;font-size:small">If you are not into the mathe=
matics just skip to 6:45 for the result.<br></div><div class=3D"gmail_defau=
lt" style=3D"font-family:comic sans ms,sans-serif;font-size:small">371,000 =
lbs (168tonnes)!!!<br></div><div class=3D"gmail_default" style=3D"font-fami=
ly:comic sans ms,sans-serif;font-size:small">Now check the structural stren=
gth of bronze... of course it varies a little with different alloys but a y=
ield strength of 650 Mpa ( 94274 p.s.i.) is typical.<br></div><div class=3D=
"gmail_default" style=3D"font-family:comic sans ms,sans-serif;font-size:sma=
ll">The mathematics required to use these numbers to calculate the forces r=
equired to radially crush a cylinder (i.e. our valve guide)=C2=A0 are a lit=
tle complex but be assured the numbers are MASSIVE.<br>So, if the wall of o=
ur guide is presumed to have an area of only 600 sq mm. (0.1 sq in), it wou=
ld take 4276 kg (9427lbf)to distort or deform it. <br></div><div class=3D"g=
mail_default" style=3D"font-family:comic sans ms,sans-serif;font-size:small=
">Now, armed with that knowledge please read my <a href=3D"http://www.netbu=
g.net/blogmichael/?p=3D384">blog post</a> carefully and you may have an ink=
ling for why I strongly advise against the use of bronze guides in a cast i=
ron head.<br><br></div><div class=3D"gmail_default" style=3D"font-family:co=
mic sans ms,sans-serif;font-size:small">Michael S<br></div><div class=3D"gm=
ail_default" style=3D"font-family:comic sans ms,sans-serif;font-size:small"=
><br></div><div class=3D"gmail_default" style=3D"font-family:comic sans ms,=
sans-serif;font-size:small"><br><br><br><br></div></div><div class=3D"gmail=
_extra"><br><div class=3D"gmail_quote">On Sun, Mar 29, 2015 at 3:25 AM, Aus=
tin Healey <span dir=3D"ltr">&lt;<a href=3D"mailto:pajtamuvek@gmail.com"; ta=
rget=3D"_blank">pajtamuvek@gmail.com</a>&gt;</span> wrote:<br><blockquote c=
lass=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;=
padding-left:1ex"><div dir=3D"ltr">Yes. This is happening. The head materia=
l expands less, the guide expand more, and thus it has to go somewhere. Met=
als are not that &quot;solid&quot; as they might look like.<div><br></div><=
div>Gergo</div></div><div class=3D"HOEnZb"><div class=3D"h5"><div class=3D"=
gmail_extra"><br><div class=3D"gmail_quote">2015-03-29 4:09 GMT+02:00 Micha=
el Salter <span dir=3D"ltr">&lt;<a href=3D"mailto:michaelsalter@gmail.com"; =
target=3D"_blank">michaelsalter@gmail.com</a>&gt;</span>:<br><blockquote cl=
ass=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;p=
adding-left:1ex"><div dir=3D"ltr"><div class=3D"gmail_default" style=3D"fon=
t-family:comic sans ms,sans-serif;font-size:small">So Gergo, <br>if I under=
stand you correctly in a situation where the guide was not installed in a h=
ead and it was then heated the outside diameter and for that matter the ins=
ide diameter of the guide would increase due to thermal expansion....correc=
t?<br></div><div class=3D"gmail_default" style=3D"font-family:comic sans ms=
,sans-serif;font-size:small">However, the difference, when the guide is ins=
talled in the head is that the head material, i.e. the hole that the guide =
is installed in, would prevent the guide from expanding or, expressed anoth=
er way, because the hole in the head would not increase in diameter as much=
 as the guide would increase in diameter the head material would effectivel=
y compress the guide and prevent it from expanding..... correct?<br><br></d=
iv><div class=3D"gmail_default" style=3D"font-family:comic sans ms,sans-ser=
if;font-size:small">Michael S<br></div></div><div><div><div class=3D"gmail_=
extra"><br><div class=3D"gmail_quote">On Sat, Mar 28, 2015 at 4:38 PM, Aust=
in Healey <span dir=3D"ltr">&lt;<a href=3D"mailto:pajtamuvek@gmail.com"; tar=
get=3D"_blank">pajtamuvek@gmail.com</a>&gt;</span> wrote:<br><blockquote cl=
ass=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;p=
adding-left:1ex"><div dir=3D"ltr">Yes it does. The material has to expand s=
omewhere. It cant go in the oposite direction.<div><br></div><div>g</div></=
div><div><div><div class=3D"gmail_extra"><br><div class=3D"gmail_quote">201=
5-03-28 20:12 GMT+01:00 Michael Salter <span dir=3D"ltr">&lt;<a href=3D"mai=
lto:michaelsalter@gmail.com" target=3D"_blank">michaelsalter@gmail.com</a>&=
gt;</span>:<br><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex=
;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"ltr"><div class=
=3D"gmail_default" style=3D"font-family:comic sans ms,sans-serif;font-size:=
small">Hi Gergo, <br>just so I&#39;m clear...you are suggesting that the in=
ternal diameter of the guide will get smaller as it heats up therefore that=
 extra clearance is required?<br></div><div class=3D"gmail_default" style=
=3D"font-family:comic sans ms,sans-serif;font-size:small">Michael S<br></di=
v></div><div><div><div class=3D"gmail_extra"><br><div class=3D"gmail_quote"=
>On Sat, Mar 28, 2015 at 3:08 AM, Austin Healey <span dir=3D"ltr">&lt;<a hr=
ef=3D"mailto:pajtamuvek@gmail.com"; target=3D"_blank">pajtamuvek@gmail.com</=
a>&gt;</span> wrote:<br><blockquote class=3D"gmail_quote" style=3D"margin:0=
 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"ltr">Bro=
nze guides expand more when they heat up. Thats why You have to use greater=
 clearance. But when they work, the clearance will be the same. Worn out gu=
ides have two negative side effects: oil consumption, and premature wear on=
 the valves as they dissipate heat slower due to rocking on the valve seat.=
 The exhaust guides are more prone to oil consumption, exhaust guides are m=
ore prone to overheating.<div><br></div><div>Gergo</div></div><div class=3D=
"gmail_extra"><br><div class=3D"gmail_quote"><div><div>2015-03-27 20:01 GMT=
+01:00 Michael Salter <span dir=3D"ltr">&lt;<a href=3D"mailto:michaelsalter=
@gmail.com" target=3D"_blank">michaelsalter@gmail.com</a>&gt;</span>:<br></=
div></div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;bord=
er-left:1px #ccc solid;padding-left:1ex"><div><div><div dir=3D"ltr"><div cl=
ass=3D"gmail_default" style=3D"font-family:comic sans ms,sans-serif;font-si=
ze:small">Hi Raymond, <br></div><div class=3D"gmail_default" style=3D"font-=
family:comic sans ms,sans-serif;font-size:small">The factory specification =
calls for 0.0025 to 0.0015 clearance for the inlets and 0.002 to 0.001 clea=
rance for the exhausts if you are using cast iron guides however if you are=
 using bronze THAT WILL NOT WORK!!!<br></div><div class=3D"gmail_default" s=
tyle=3D"font-family:comic sans ms,sans-serif;font-size:small">To be safe wi=
th bronze guides you will have to hog them out to about 0.006&quot; clearan=
ce..which means there is really no point in replacing them.<br></div><div c=
lass=3D"gmail_default" style=3D"font-family:comic sans ms,sans-serif;font-s=
ize:small">I would point you to <a href=3D"http://www.netbug.net/blogmichae=
l/?p=3D384" target=3D"_blank">this article</a> on my blog...been there done=
 that...<br><br></div><div class=3D"gmail_default" style=3D"font-family:com=
ic sans ms,sans-serif;font-size:small">Michael S<br></div><div class=3D"gma=
il_default" style=3D"font-family:comic sans ms,sans-serif;font-size:small">=
BN1 #174<br></div></div><div class=3D"gmail_extra"><br><div class=3D"gmail_=
quote"><span>On Fri, Mar 27, 2015 at 2:17 PM, RAYMOND SMITHSON <span dir=3D=
"ltr">&lt;<a href=3D"mailto:rjsmithson@shaw.ca"; target=3D"_blank">rjsmithso=
n@shaw.ca</a>&gt;</span> wrote:<br></span><blockquote class=3D"gmail_quote"=
 style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><s=
pan><div><div style=3D"font-family:arial,helvetica,sans-serif;font-size:10p=
t;color:#000000">I am rebuilding my 3000 cylinder head and have found the i=
nlet valve stems have .008&quot; clearance but the exhaust stems have only =
.002&quot; clearance. Does anyone know if this is common?</div></div><br></=
span>_______________________________________________<br>
nk">http://www.team.net/donate.html</a><br>
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<br>
<br></blockquote></div><span><font color=3D"#888888"><br><br clear=3D"all">=
<br>-- <br><div><div dir=3D"ltr"><div><div dir=3D"ltr"><i><font><span style=
=3D"color:black">If you can&#39;t fix it with a hammer, you&#39;ve got an e=
lectrical problem.</span></font></i><br><br><div></div><div></div><div></di=
v></div></div></div></div>
</font></span></div>
<br>_______________________________________________<br>
nk">http://www.team.net/donate.html</a><br>
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.team.net/forums</a><br>
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ions/healeys/pajtamuvek@gmail.com</a><br>
<br>
<br></blockquote></div><br></div>
</blockquote></div><br><br clear=3D"all"><br>-- <br><div><div dir=3D"ltr"><=
div><div dir=3D"ltr"><i><font><span style=3D"color:black">If you can&#39;t =
fix it with a hammer, you&#39;ve got an electrical problem.</span></font></=
i><br><br><div></div><div></div><div></div></div></div></div></div>
</div>
</div></div></blockquote></div><br></div>
</div></div></blockquote></div><br><br clear=3D"all"><br>-- <br><div><div d=
ir=3D"ltr"><div><div dir=3D"ltr"><i><font><span style=3D"color:black">If yo=
u can&#39;t fix it with a hammer, you&#39;ve got an electrical problem.</sp=
an></font></i><br><br><div></div><div></div><div></div></div></div></div></=
div>
</div>
</div></div></blockquote></div><br></div>
</div></div></blockquote></div><br><br clear=3D"all"><br>-- <br><div class=
=3D"gmail_signature"><div dir=3D"ltr"><div><div dir=3D"ltr"><i><font><span =
style=3D"color:black">If you can&#39;t fix it with a hammer, you&#39;ve got=
 an electrical problem.</span></font></i><br><br><div></div><div></div><div=
></div></div></div></div></div>
</div>

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