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curing my rod knock(a bit long)



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Robbie,

There is an awful lot going on here. It could be a lot of things. =
Changing the oil pump might not be a bad idea. What pressures are you =
running on idle and off idle? The way bearing clearances are measured is =
with a product called Plastigauge. You snip off a piece of this very =
precisely sized plastic and place it between the journal and the =
bearing. Torque the cap on and without moving anything take the cap off. =
The plastic will have been crushed. Measure the width of the crushed =
plastic and that will tell you volumes about your bearings. This can be =
done with the engine in the car and that is what I'd do first.

Rick Alexander

----- Original Message -----=20
  From: Robbie Cotner=20
  To: scirocco-l@scirocco.org=20
  Sent: Sunday, February 02, 2003 1:53 PM
  Subject: curing my rod knock(a bit long)


  Hey all, I could use some help here!  I rebuilt a JH with 170k, it was =
strong when I rebuilt it, since I was doing a transplant I figured that =
was a good time to rebuild it.  The crank was mic'd(sp?) within spec, =
and I used OEM size bearings.  When assembling the engine, I got the #1 =
and #3 rods mixed up, which made the engine VERY hard to turn by torque =
bar.  I'm 19, in a hurry, and immature, so I figured I'd "break the =
engine in" by hand and turned it 100 times in each direction(wasn't hard =
to keep moving once you got it moving).  That didn't help, and =
eventually I figured out what was wrong but not before one of the rod =
bearings was a bit pre-broken in(very shiny compared to the others which =
were not shiny at all).  Well I switched the rods back, which may have =
both fixed and caused a problem since I had to undo the stretch bolts =
(which were new, but in the case of #1 and #3 had been torqued once, =
removed and retorqued again). =20

  I assembled the engine and it ran great over the summer, putting on =
about 6,000 miles(a lot of road tripping).  Now that winter is here it =
knocks when it's below freezing(32F) for about a minute.  However, if I =
start the engine and rev it to about 2-3k for a second, the knock goes =
away(if it's really cold it doesnt' though).  The knock isn't loud, but =
it's there. =20

  Also when rebuilding the engine I reused the original oil pump(with =
about 180k on it now).  All I did was clean it, and put it back in.  I =
did not notice any scoring in it. =20

  So now the big question, could I blame this knock on the oil pump not =
getting oil to something or another quickly enough?  Or is it too much =
rod/crank clearance?  Could it be to much wrist pin/piston clearance?  =
What should I do?  If it is too much rod clearance, can I order a set of =
new bearings and rod bolts, take off the oil pan, and put em =
on(hopefully curing the problem)?  The engine far as I know only knocks =
when cold, not when under load.  A very big thanks to all who have read =
all of this, and an even bigger thanks to those who reply!

  -Rob





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</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><STRONG>Robbie,</STRONG></DIV>
<DIV><STRONG></STRONG>&nbsp;</DIV>
<DIV><STRONG>There is an awful lot going on here. It could be a lot of =
things.=20
Changing the oil pump might not be a bad idea. What pressures are you =
running on=20
idle and off idle? The way bearing clearances are measured is with a =
product=20
called Plastigauge. You snip off a piece of this very precisely sized =
plastic=20
and place it between the journal and the bearing. Torque the cap on and =
without=20
moving anything take the cap off. The plastic will have been crushed. =
Measure=20
the width of the crushed plastic and that will tell you volumes about =
your=20
bearings. This can be done with the engine in the car and that is what =
I'd do=20
first.</STRONG></DIV>
<DIV><STRONG></STRONG>&nbsp;</DIV>
<DIV><STRONG>Rick Alexander</STRONG></DIV>
<DIV>&nbsp;</DIV>
<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE=20
style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; =
BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
  <DIV=20
  style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>=20
  <A title=3Drobw_z@yahoo.com href=3D"mailto:robw_z@yahoo.com";>Robbie =
Cotner</A>=20
  </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A =
title=3Dscirocco-l@scirocco.org=20
  href=3D"mailto:scirocco-l@scirocco.org";>scirocco-l@scirocco.org</A> =
</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Sunday, February 02, 2003 =
1:53=20
  PM</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> curing my rod knock(a =
bit=20
  long)</DIV>
  <DIV><BR></DIV>
  <P>Hey all, I could use some help here!&nbsp; I rebuilt a JH with =
170k, it was=20
  strong when I rebuilt it, since I was doing a transplant I figured =
that was a=20
  good time to rebuild it.&nbsp; The crank was mic'd(sp?) within spec, =
and I=20
  used OEM size bearings.&nbsp; When assembling the engine, I got the #1 =
and #3=20
  rods mixed up, which&nbsp;made the engine VERY hard to turn by torque=20
  bar.&nbsp; I'm 19, in a hurry, and immature, so I figured I'd "break =
the=20
  engine in" by hand and turned it 100 times in each direction(wasn't =
hard to=20
  keep moving&nbsp;once you got it moving).&nbsp; That didn't help, and=20
  eventually I figured out what was wrong but not before one of the rod =
bearings=20
  was a bit pre-broken in(very shiny compared to the others which were =
not shiny=20
  at all).&nbsp; Well I switched the rods back, which may have both =
fixed and=20
  caused a problem since I had to undo the stretch bolts (which were =
new, but in=20
  the case of #1 and #3 had been torqued once, removed and retorqued=20
  again).&nbsp; </P>
  <P>I assembled the engine and it ran great over the summer, putting on =

  about&nbsp;6,000 miles(a lot of road tripping).&nbsp; Now that winter =
is=20
  here&nbsp;it knocks when&nbsp;it's below&nbsp;freezing(32F) for about =
a=20
  minute.&nbsp; However, if I start the engine and rev it to about 2-3k =
for a=20
  second, the knock goes away(if it's really cold it doesnt' =
though).&nbsp; The=20
  knock isn't loud, but it's there.&nbsp; </P>
  <P>Also when rebuilding the engine I reused the original oil pump(with =
about=20
  180k on it now).&nbsp; All I did was clean it, and put it back =
in.&nbsp; I did=20
  not notice any scoring in it.&nbsp; </P>
  <P>So now the big question, could I blame this knock on the oil pump =
not=20
  getting oil to something or another quickly enough?&nbsp; Or is it too =
much=20
  rod/crank clearance?&nbsp; Could it be to much wrist pin/piston=20
  clearance?&nbsp; What should I do?&nbsp; If it is too much rod =
clearance, can=20
  I order a set of new bearings and rod bolts, take off the oil pan, and =
put em=20
  on(hopefully curing the problem)?&nbsp; The engine far as I know only =
knocks=20
  when cold, not when under load.&nbsp; A very big thanks to all who =
have read=20
  all of this, and an even bigger thanks to those who reply!</P>
  <P>-Rob</P>
  <P><BR>
  <HR SIZE=3D1>
  Do you Yahoo!?<BR><A=20
  =
href=3D"http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com";>Yaho=
o! Mail=20
  Plus</A> - Powerful. Affordable. <A=20
  =
href=3D"http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com";>Sign=
 up=20
  now</A></BLOCKQUOTE></BODY></HTML>

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