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| [GMCnet] Motor Knocking Part 2 [message #204185] |
Tue, 09 April 2013 18:39  |
Richard Waters
Messages: 4
Registered: February 2004
Karma: 0
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Junior Member |
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Continuation of my tale of woe:
I consulted Ken, Emery and Matt on what to do about that. Matt wrote me and
said, "It is my experience that the primary leakage of coolant into lube oil
is across the head gasket body. If there was a combustion seal failure, it
would have been evident in the coolant. (It makes it muddy pretty fast.)
That being the case. After you have finished looking for external leaks and
if you found none, try "pulling" on the cylinder head bolts. This is a PITA
operation because the cylinder head covers have to come off. Get that all
that stuff on top cleared away and find a flexible bean torque wrench.
(Yes, the cheap kind and there is a reason). Olds spec for final torque is
85#ft. Pull on each bolt at that level, and if it moves keep pulling to 85.
(The pattern is not important.) If they don't move, (this is where the beam
wrench is important) make a mental note of where in space the end of the
pointer is, and crack the fastener back off. Now, pull it up again and I
will bet you that you get a few more degrees on that pointer. (Now, exhale
and hope that was the problem.) If you gain fastener rotation on any, you
will probably gain it on all. The reason you had to back them up is simply
that the threads stick. That "break-away" torque often exceeds the
installed torque even though the fastener has lost tension. What has
happened is the head gasket material has what is called creep. That means
that the fasteners their lost tension that was compressing the gasket body.
Now, you are getting that tension back. That tension recovery could easily
be enough to close off an internal coolant leak."
Since I am sure Matt knows what he is talking about, I pulled both rocker
covers and checked the torque tension per his suggestion. The driver side
was inconclusive. I couldn't tell much except that the bolts seemed to be
torqued to 85 and when I backed them off and retorqed them, there didn't
seem to be change in the position of my 50 year old beam torque wrench.
Then I did the same to the passenger side. All of the bolts, except the one
next to the center exhaust port, snapped (they moved) when I approached 85
foot pounds. So could it be that the head on the passenger side was not
torqued to spec during rebuild? I was discouraged that the builder
apparently didn't torque the passenger side to spec, but that perhaps I
sealed the leak. In addition, per Emery's recommendation I drained, flushed
and refilled the coolant and added Bar's stop leak. So I put everything back
together and got ready to leave on our trip. I ran the engine a few times
after that without incident. Then the knock started the day before we were
leaving.
Ken was nice about it, but I am sure he figured I messed something up when I
was in there checking the torque. I had to agree, having made more than my
share of mistakes repairing stuff, so I didn't feel too bad about taking the
covers off again. I'm now an expert at taking those things off. Sadly, I
still can't find where the knocking sound is coming from and nothing seemed
to be molested or left behind by my previous work. So today I pulled both
rocker covers off and couldn't find anything loose or anything in there that
wasn't supposed to be there. I also ran the engine and listened to each
rocker with my stethoscope and couldn't hear anything related to the knock.
Of course I am a novice at listening to engine noises. I learned that that
you can run a 455 for a short time with the covers off and not make a mess.
I put it all back together, with no plan in mind on how to fix the problem.
Some will say it's time for another new motor. If that's the case the GMC
will have to become a yard ornament for a while.
Any ideas, anyone what could be knocking? It started suddenly and is pretty
loud. I have not driven it since it started and have probably less than 10
minutes total time running with the knock.
Richard
SE Michigan
www.PalmBeachGMC.com
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| Re: [GMCnet] Motor Knocking Part 2 [message #204188 is a reply to message #204185] |
Tue, 09 April 2013 18:58  |
kerry pinkerton
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
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Richard, I'm somewhat concerned that you don't see any change in the noise when you short the plug wires but that wouldn't necessarily quiet a collapsed lifter. It SHOULD however make a change if the noise is in the crank or piston.
I don't know about Olds engines but on some engines, you can pull the lifters out without removing anything but the rocker arms. There is a tool that you squeeze and it spreads a couple fingers out and grabs the lifter. Someone will know if you can do it on our Olds. If so, lifters are cheap.
10000 mile engines should not go bad unless they were built by idiots although 'stuff' happens from time to time even with the best rebuilders.
Kerry Pinkerton - North Alabama
Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
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| Re: [GMCnet] Motor Knocking Part 2 [message #204192 is a reply to message #204185] |
Tue, 09 April 2013 19:12 |
Bruce Hart
Messages: 1501
Registered: October 2011
Location: La Grange, Wyoming
Karma: 5
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Senior Member |
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Could be an exhaust leak from exhaust manifold, most likely the passenger
side, due to the manifold having a crack. Since you were in this area and
the knock went away for a bit. Could also be a lifter knocking.
On Tue, Apr 9, 2013 at 5:39 PM, Richard Waters <mygmc@palmbeachgmc.com>wrote:
> Continuation of my tale of woe:
>
> I consulted Ken, Emery and Matt on what to do about that. Matt wrote me
> and
> said, "It is my experience that the primary leakage of coolant into lube
> oil
> is across the head gasket body. If there was a combustion seal failure, it
> would have been evident in the coolant. (It makes it muddy pretty fast.)
> That being the case. After you have finished looking for external leaks
> and
> if you found none, try "pulling" on the cylinder head bolts. This is a
> PITA
> operation because the cylinder head covers have to come off. Get that all
> that stuff on top cleared away and find a flexible bean torque wrench.
> (Yes, the cheap kind and there is a reason). Olds spec for final torque
> is
> 85#ft. Pull on each bolt at that level, and if it moves keep pulling to
> 85.
> (The pattern is not important.) If they don't move, (this is where the
> beam
> wrench is important) make a mental note of where in space the end of the
> pointer is, and crack the fastener back off. Now, pull it up again and I
> will bet you that you get a few more degrees on that pointer. (Now, exhale
> and hope that was the problem.) If you gain fastener rotation on any, you
> will probably gain it on all. The reason you had to back them up is simply
> that the threads stick. That "break-away" torque often exceeds the
> installed torque even though the fastener has lost tension. What has
> happened is the head gasket material has what is called creep. That means
> that the fasteners their lost tension that was compressing the gasket body.
> Now, you are getting that tension back. That tension recovery could easily
> be enough to close off an internal coolant leak."
>
> Since I am sure Matt knows what he is talking about, I pulled both rocker
> covers and checked the torque tension per his suggestion. The driver side
> was inconclusive. I couldn't tell much except that the bolts seemed to be
> torqued to 85 and when I backed them off and retorqed them, there didn't
> seem to be change in the position of my 50 year old beam torque wrench.
> Then I did the same to the passenger side. All of the bolts, except the
> one
> next to the center exhaust port, snapped (they moved) when I approached 85
> foot pounds. So could it be that the head on the passenger side was not
> torqued to spec during rebuild? I was discouraged that the builder
> apparently didn't torque the passenger side to spec, but that perhaps I
> sealed the leak. In addition, per Emery's recommendation I drained,
> flushed
> and refilled the coolant and added Bar's stop leak. So I put everything
> back
> together and got ready to leave on our trip. I ran the engine a few times
> after that without incident. Then the knock started the day before we were
> leaving.
>
> Ken was nice about it, but I am sure he figured I messed something up when
> I
> was in there checking the torque. I had to agree, having made more than my
> share of mistakes repairing stuff, so I didn't feel too bad about taking
> the
> covers off again. I'm now an expert at taking those things off. Sadly, I
> still can't find where the knocking sound is coming from and nothing seemed
> to be molested or left behind by my previous work. So today I pulled both
> rocker covers off and couldn't find anything loose or anything in there
> that
> wasn't supposed to be there. I also ran the engine and listened to each
> rocker with my stethoscope and couldn't hear anything related to the knock.
> Of course I am a novice at listening to engine noises. I learned that
> that
> you can run a 455 for a short time with the covers off and not make a mess.
> I put it all back together, with no plan in mind on how to fix the problem.
> Some will say it's time for another new motor. If that's the case the GMC
> will have to become a yard ornament for a while.
>
> Any ideas, anyone what could be knocking? It started suddenly and is
> pretty
> loud. I have not driven it since it started and have probably less than 10
> minutes total time running with the knock.
>
> Richard
>
> SE Michigan
>
> www.PalmBeachGMC.com
>
>
>
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart
1976 Palm Beach
1977 28' Kingsley
La Grange, Wyoming
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| Re: [GMCnet] Motor Knocking Part 2 [message #204194 is a reply to message #204185] |
Tue, 09 April 2013 19:17 |
Sandra Price
Messages: 709
Registered: May 2006
Karma: 1
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Senior Member |
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Richard, I suggest you crank it up. When it starts knocking, pull one
spark plug wire off the distributer cap at a time until you find which
cylinder is knocking. Then check the push rods on that cylinder to be sure
they are straight. If, not replace them and check how it runs. OR, it
could a bad lifter. Let me know what you find.
Bob Price, standing by
On Apr 9, 2013 6:41 PM, "Richard Waters" <mygmc@palmbeachgmc.com> wrote:
> Continuation of my tale of woe:
>
> I consulted Ken, Emery and Matt on what to do about that. Matt wrote me
> and
> said, "It is my experience that the primary leakage of coolant into lube
> oil
> is across the head gasket body. If there was a combustion seal failure, it
> would have been evident in the coolant. (It makes it muddy pretty fast.)
> That being the case. After you have finished looking for external leaks
> and
> if you found none, try "pulling" on the cylinder head bolts. This is a
> PITA
> operation because the cylinder head covers have to come off. Get that all
> that stuff on top cleared away and find a flexible bean torque wrench.
> (Yes, the cheap kind and there is a reason). Olds spec for final torque
> is
> 85#ft. Pull on each bolt at that level, and if it moves keep pulling to
> 85.
> (The pattern is not important.) If they don't move, (this is where the
> beam
> wrench is important) make a mental note of where in space the end of the
> pointer is, and crack the fastener back off. Now, pull it up again and I
> will bet you that you get a few more degrees on that pointer. (Now, exhale
> and hope that was the problem.) If you gain fastener rotation on any, you
> will probably gain it on all. The reason you had to back them up is simply
> that the threads stick. That "break-away" torque often exceeds the
> installed torque even though the fastener has lost tension. What has
> happened is the head gasket material has what is called creep. That means
> that the fasteners their lost tension that was compressing the gasket body.
> Now, you are getting that tension back. That tension recovery could easily
> be enough to close off an internal coolant leak."
>
> Since I am sure Matt knows what he is talking about, I pulled both rocker
> covers and checked the torque tension per his suggestion. The driver side
> was inconclusive. I couldn't tell much except that the bolts seemed to be
> torqued to 85 and when I backed them off and retorqed them, there didn't
> seem to be change in the position of my 50 year old beam torque wrench.
> Then I did the same to the passenger side. All of the bolts, except the
> one
> next to the center exhaust port, snapped (they moved) when I approached 85
> foot pounds. So could it be that the head on the passenger side was not
> torqued to spec during rebuild? I was discouraged that the builder
> apparently didn't torque the passenger side to spec, but that perhaps I
> sealed the leak. In addition, per Emery's recommendation I drained,
> flushed
> and refilled the coolant and added Bar's stop leak. So I put everything
> back
> together and got ready to leave on our trip. I ran the engine a few times
> after that without incident. Then the knock started the day before we were
> leaving.
>
> Ken was nice about it, but I am sure he figured I messed something up when
> I
> was in there checking the torque. I had to agree, having made more than my
> share of mistakes repairing stuff, so I didn't feel too bad about taking
> the
> covers off again. I'm now an expert at taking those things off. Sadly, I
> still can't find where the knocking sound is coming from and nothing seemed
> to be molested or left behind by my previous work. So today I pulled both
> rocker covers off and couldn't find anything loose or anything in there
> that
> wasn't supposed to be there. I also ran the engine and listened to each
> rocker with my stethoscope and couldn't hear anything related to the knock.
> Of course I am a novice at listening to engine noises. I learned that
> that
> you can run a 455 for a short time with the covers off and not make a mess.
> I put it all back together, with no plan in mind on how to fix the problem.
> Some will say it's time for another new motor. If that's the case the GMC
> will have to become a yard ornament for a while.
>
> Any ideas, anyone what could be knocking? It started suddenly and is
> pretty
> loud. I have not driven it since it started and have probably less than 10
> minutes total time running with the knock.
>
> Richard
>
> SE Michigan
>
> www.PalmBeachGMC.com
>
>
>
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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| Re: [GMCnet] Motor Knocking Part 2 [message #204195 is a reply to message #204188] |
Tue, 09 April 2013 19:24 |
jhb1
Messages: 303
Registered: February 2004
Karma: 0
|
Senior Member |
|
|
Have you tried the mechanical fuel pump mine started to make a knocking noise years ago before I switched to an electric pump to combat vapour lock when it first started I thought a rod bearing had gone out.
HTH
| Kerry Pinkerton wrote on Tue, 09 April 2013 19:58 |
Richard, I'm somewhat concerned that you don't see any change in the noise when you short the plug wires but that wouldn't necessarily quiet a collapsed lifter. It SHOULD however make a change if the noise is in the crank or piston.
I don't know about Olds engines but on some engines, you can pull the lifters out without removing anything but the rocker arms. There is a tool that you squeeze and it spreads a couple fingers out and grabs the lifter. Someone will know if you can do it on our Olds. If so, lifters are cheap.
10000 mile engines should not go bad unless they were built by idiots although 'stuff' happens from time to time even with the best rebuilders.
|
John H. Bell
77 Royale; QuadBag,Manny OneTon,Honda EV4010, FITech
Montreal Qc.
|
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|
|
| Re: [GMCnet] Motor Knocking Part 2 [message #204196 is a reply to message #204185] |
Tue, 09 April 2013 19:22 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Richard,
If it IS a collapsed lifter, you should be able to affect the sound by
pressing on each rocker (use a wooden stick) in turn.
OH NO! You already reassembled the rocker covers!
Ken H.
On Tue, Apr 9, 2013 at 7:39 PM, Richard Waters <mygmc@palmbeachgmc.com>wrote:
> Continuation of my tale of woe:
> ... today I pulled both
> rocker covers off and couldn't find anything loose or anything in there
> that
> wasn't supposed to be there. I also ran the engine and listened to each
> rocker with my stethoscope and couldn't hear anything related to the
> knock...
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] Motor Knocking Part 2 [message #204197 is a reply to message #204194] |
Tue, 09 April 2013 19:27 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
I hate to be the bearer of bad tidings, but you better check your camshaft
lobes. Many times lifters start making noise when there is not enough
preload to take up the internal plunges travel. Flat tappet camshafts do
not like the new low zinc oils.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Apr 9, 2013 5:17 PM, "Sandra Price" <bsprice9359@gmail.com> wrote:
> Richard, I suggest you crank it up. When it starts knocking, pull one
> spark plug wire off the distributer cap at a time until you find which
> cylinder is knocking. Then check the push rods on that cylinder to be sure
> they are straight. If, not replace them and check how it runs. OR, it
> could a bad lifter. Let me know what you find.
>
> Bob Price, standing by
> On Apr 9, 2013 6:41 PM, "Richard Waters" <mygmc@palmbeachgmc.com> wrote:
>
> > Continuation of my tale of woe:
> >
> > I consulted Ken, Emery and Matt on what to do about that. Matt wrote me
> > and
> > said, "It is my experience that the primary leakage of coolant into lube
> > oil
> > is across the head gasket body. If there was a combustion seal failure,
> it
> > would have been evident in the coolant. (It makes it muddy pretty fast.)
> > That being the case. After you have finished looking for external leaks
> > and
> > if you found none, try "pulling" on the cylinder head bolts. This is a
> > PITA
> > operation because the cylinder head covers have to come off. Get that all
> > that stuff on top cleared away and find a flexible bean torque wrench.
> > (Yes, the cheap kind and there is a reason). Olds spec for final torque
> > is
> > 85#ft. Pull on each bolt at that level, and if it moves keep pulling to
> > 85.
> > (The pattern is not important.) If they don't move, (this is where the
> > beam
> > wrench is important) make a mental note of where in space the end of the
> > pointer is, and crack the fastener back off. Now, pull it up again and I
> > will bet you that you get a few more degrees on that pointer. (Now,
> exhale
> > and hope that was the problem.) If you gain fastener rotation on any,
> you
> > will probably gain it on all. The reason you had to back them up is
> simply
> > that the threads stick. That "break-away" torque often exceeds the
> > installed torque even though the fastener has lost tension. What has
> > happened is the head gasket material has what is called creep. That
> means
> > that the fasteners their lost tension that was compressing the gasket
> body.
> > Now, you are getting that tension back. That tension recovery could
> easily
> > be enough to close off an internal coolant leak."
> >
> > Since I am sure Matt knows what he is talking about, I pulled both rocker
> > covers and checked the torque tension per his suggestion. The driver
> side
> > was inconclusive. I couldn't tell much except that the bolts seemed to
> be
> > torqued to 85 and when I backed them off and retorqed them, there didn't
> > seem to be change in the position of my 50 year old beam torque wrench.
> > Then I did the same to the passenger side. All of the bolts, except the
> > one
> > next to the center exhaust port, snapped (they moved) when I approached
> 85
> > foot pounds. So could it be that the head on the passenger side was not
> > torqued to spec during rebuild? I was discouraged that the builder
> > apparently didn't torque the passenger side to spec, but that perhaps I
> > sealed the leak. In addition, per Emery's recommendation I drained,
> > flushed
> > and refilled the coolant and added Bar's stop leak. So I put everything
> > back
> > together and got ready to leave on our trip. I ran the engine a few
> times
> > after that without incident. Then the knock started the day before we
> were
> > leaving.
> >
> > Ken was nice about it, but I am sure he figured I messed something up
> when
> > I
> > was in there checking the torque. I had to agree, having made more than
> my
> > share of mistakes repairing stuff, so I didn't feel too bad about taking
> > the
> > covers off again. I'm now an expert at taking those things off. Sadly,
> I
> > still can't find where the knocking sound is coming from and nothing
> seemed
> > to be molested or left behind by my previous work. So today I pulled
> both
> > rocker covers off and couldn't find anything loose or anything in there
> > that
> > wasn't supposed to be there. I also ran the engine and listened to each
> > rocker with my stethoscope and couldn't hear anything related to the
> knock.
> > Of course I am a novice at listening to engine noises. I learned that
> > that
> > you can run a 455 for a short time with the covers off and not make a
> mess.
> > I put it all back together, with no plan in mind on how to fix the
> problem.
> > Some will say it's time for another new motor. If that's the case the
> GMC
> > will have to become a yard ornament for a while.
> >
> > Any ideas, anyone what could be knocking? It started suddenly and is
> > pretty
> > loud. I have not driven it since it started and have probably less than
> 10
> > minutes total time running with the knock.
> >
> > Richard
> >
> > SE Michigan
> >
> > www.PalmBeachGMC.com
> >
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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| Re: [GMCnet] Motor Knocking Part 2 [message #204198 is a reply to message #204195] |
Tue, 09 April 2013 19:26 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Richard,
Now THAT's a good suggestion that had escaped me!!! Would occur at 1/2
engine speed since it runs off the camshaft. Could easily happen suddenly
too.
Ken H.
On Tue, Apr 9, 2013 at 8:24 PM, jhb1 wrote:
>
>
> Have you tried the mechanical fuel pump mine started to make a knocking
> noise years ago before I switched to an electric pump to combat vapour lock
> when it first started I thought a rod bearing had gone out.
> --
> John H. Bell
> 77 Royale
> Montreal Qc.
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] Motor Knocking Part 2 [message #204199 is a reply to message #204194] |
Tue, 09 April 2013 19:33 |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
|
Senior Member |
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I`d go with Bob and pull wires one at a time. Idle it up a little to get knock the loudest. If the knock changes that cyl has a problem. If the knock does not change it could be a bad harmonic balancer, cracked flexplate or lose torque converter/flexplate bolts. Could be exhaust but you should be able to feel that. Check the heat tube gasket on top of intake next to carb. A manual fuel pump can also knock if bad.
[quote title=Sandra Price wrote on Tue, 09 April 2013 20:17]Richard, I suggest you crank it up. When it starts knocking, pull one
spark plug wire off the distributer cap at a time until you find which
cylinder is knocking. Then check the push rods on that cylinder to be sure
they are straight. If, not replace them and check how it runs. OR, it
could a bad lifter. Let me know what you find.
Bob Price, standing by
On Apr 9, 2013 6:41 PM, "Richard Waters" <mygmc@palmbeachgmc.com> wrote:
C. Boyd
76 Crestmont
East Tennessee
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| Re: [GMCnet] Motor Knocking Part 2 [message #204200 is a reply to message #204199] |
Tue, 09 April 2013 19:35 |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
|
Senior Member |
|
|
Should read bad or loose harmonic balancer or pulley.
[quote title=C Boyd wrote on Tue, 09 April 2013 20:33]I`d go with Bob and pull wires one at a time. Idle it up a little to get knock the loudest. If the knock changes that cyl has a problem. If the knock does not change it could be a bad harmonic balancer, cracked flexplate or lose torque converter/flexplate bolts. Could be exhaust but you should be able to feel that. Check the heat tube gasket on top of intake next to carb. A manual fuel pump can also knock if bad.
| Sandra Price wrote on Tue, 09 April 2013 20:17 |
Richard, I suggest you crank it up. When it starts knocking, pull one
spark plug wire off the distributer cap at a time until you find which
cylinder is knocking. Then check the push rods on that cylinder to be sure
they are straight. If, not replace them and check how it runs. OR, it
could a bad lifter. Let me know what you find.
Bob Price, standing by
On Apr 9, 2013 6:41 PM, "Richard Waters" <mygmc@palmbeachgmc.com> wrote:
|
C. Boyd
76 Crestmont
East Tennessee
|
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|
|
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| Re: [GMCnet] Motor Knocking Part 2 [message #204203 is a reply to message #204197] |
Tue, 09 April 2013 20:19 |
kerry pinkerton
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
|
Senior Member |
|
|
| James Hupy wrote on Tue, 09 April 2013 19:27 |
I hate to be the bearer of bad tidings, but you better check your camshaft
lobes. Many times lifters start making noise when there is not enough
preload to take up the internal plunges travel. Flat tappet camshafts do
not like the new low zinc oils.
Jim Hupy...
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True but every cam I've ever seen go bad to the noise level made the motor run like you dropped a cylinder...which in effect you had.
Big Block Chebbies are bad about wiping cam lobes
Kerry Pinkerton - North Alabama
Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
[Updated on: Tue, 09 April 2013 20:35] Report message to a moderator |
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| Re: [GMCnet] Motor Knocking Part 2 [message #204257 is a reply to message #204205] |
Wed, 10 April 2013 09:23 |
rjw
Messages: 697
Registered: September 2005
Karma: 4
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Senior Member |
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I'm not sure how to properly reply to a thread on the phorum, but here goes.
Thanks everyone for the suggestions. However, none of them was what I just found out to be the cause of the "knocking" sound.
I’m happy to report, that between Ken Henderson you and our cat, I solved the problem. Ken had previously written me and said, “Sad to say, you need to look in the mirror. (Or, more generously, think back VERY carefully about everything you did with the rocker covers off.)”. Well I didn’t think about all the things that I did before the knock started.
Last night, I must have been dreaming about what turns ½ speed on the engine besides the valve train. During my dream our cat jumped on the bed and started rubbing her face against my ear and I dreamed that she told me “distributor”. I woke up and realized that I had indeed been fooling with the distributor prior to the knocking sound. I had just installed a set of new ignition wires and when I went to install the air cleaner the new wires seemed to interfere with the air cleaner more than before (as some may know it’s very tight there because of fact I have fuel injection). In my haste to get the air cleaner on, I figured I might have nudged the cap enough to cause the rotor to hit something inside at valve train speed. So I went out to the coach and looked at the distributor and noticed right way that the cap was indeed cocked. I took the cap off and everything inside seemed OK. I reinstalled it correctly and started the engine. OMG no KNOCK! Amazing that the distributor could be that loud!
I wasted a lot of time on this, but on the plus side, I have become an expert on how to speedily remove and replace valve covers on Olds 455s.
Thanks to all that responded to my query,
Richard
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| Re: [GMCnet] Motor Knocking Part 2 [message #204259 is a reply to message #204257] |
Wed, 10 April 2013 09:34 |
Ray Erspamer
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
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Senior Member |
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WOW, is this a great ending to what could have been an ugly story. My wife
always tells me, things pop into our minds for a reason and when they do we need
TO LISTEN !
So happy you found the problem and it was a simple fix. Now GO and enjoy your
vacation !!!
As some of you know I've also done a few things that have caused me problems, I
hate when that happens but when I look back, it's all part of THE GMC STORY we
all have !
ENJOY Richard!! If you ever get near Milwaukee, be sure to stop in !!!
Ray
Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/
________________________________
From: RJW <old76@palmbeachgmc.com>
To: gmclist@temp.gmcnet.org
Sent: Wed, April 10, 2013 9:23:33 AM
Subject: Re: [GMCnet] Motor Knocking Part 2
I'm not sure how to properly reply to a thread on the phorum, but here goes.
Thanks everyone for the suggestions. However, none of them was what I just found
out to be the cause of the "knocking" sound.
I’m happy to report, that between Ken Henderson you and our cat, I solved the
problem. Ken had previously written me and said, “Sad to say, you need to look
in the mirror. (Or, more generously, think back VERY carefully about everything
you did with the rocker covers off.)”. Well I didn’t think about all the things
that I did before the knock started.
Last night, I must have been dreaming about what turns œ speed on the engine
besides the valve train. During my dream our cat jumped on the bed and started
rubbing her face against my ear and I dreamed that she told me “distributor”. I
woke up and realized that I had indeed been fooling with the distributor prior
to the knocking sound. I had just installed a set of new ignition wires and
when I went to install the air cleaner the new wires seemed to interfere with
the air cleaner more than before (as some may know it’s very tight there because
of fact I have fuel injection). In my haste to get the air cleaner on, I figured
I might have nudged the cap enough to cause the rotor to hit something inside at
valve train speed. So I went out to the coach and looked at the distributor and
noticed right way that the cap was indeed cocked. I took the cap off and
everything inside seemed OK. I reinstalled it correctly and started the
engine. OMG no KNOCK! Amazing that the distributor could be that loud!
I wasted a lot of time on this, but on the plus side, I have become an expert on
how to speedily remove and replace valve covers on Olds 455s.
Thanks to all that responded to my query,
Richard
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ray Erspamer
78 GMC Royale Center Kitchen
403, 3.70 Final Drive
Holley Sniper Quadrajet EFI System,
Holley Hyperspark Ignition System
414-484-9431
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| Re: [GMCnet] Motor Knocking Part 2 [message #204260 is a reply to message #204257] |
Wed, 10 April 2013 09:36 |
George Beckman
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
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Senior Member |
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| rjw wrote on Wed, 10 April 2013 07:23 |
I'm not sure how to properly reply to a thread on the phorum, but here goes.
Thanks everyone for the suggestions. However, none of them was what I just found out to be the cause of the "knocking" sound.
I’m happy to report, that between Ken Henderson you and our cat, I solved the problem. Ken had previously written me and said, “Sad to say, you need to look in the mirror. (Or, more generously, think back VERY carefully about everything you did with the rocker covers off.)”. Well I didn’t think about all the things that I did before the knock started.
Last night, I must have been dreaming about what turns ½ speed on the engine besides the valve train. During my dream our cat jumped on the bed and started rubbing her face against my ear and I dreamed that she told me “distributor”. I woke up and realized that I had indeed been fooling with the distributor prior to the knocking sound. I had just installed a set of new ignition wires and when I went to install the air cleaner the new wires seemed to interfere with the air cleaner more than before (as some may know it’s very tight there because of fact I have fuel injection). In my haste to get the air cleaner on, I figured I might have nudged the cap enough to cause the rotor to hit something inside at valve train speed. So I went out to the coach and looked at the distributor and noticed right way that the cap was indeed cocked. I took the cap off and everything inside seemed OK. I reinstalled it correctly and started the engine. OMG no KNOCK! Amazing that the distributor could be that loud!
Thanks to all that responded to my query,
Richard
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This is great news. I am not a big cat lover, but am willing to give the beast some credit.
Hopefully the coolant will stop seeping in with the head torqued a bit more and you can enjoy a nice extended trip. You have had your share of troubles with that engine.
Good to have learned abut the distributor cap being able to make that much noise. We all keep learning from these little events.
'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
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| Re: [GMCnet] Motor Knocking Part 2 [message #204263 is a reply to message #204260] |
Wed, 10 April 2013 10:20 |
habbyguy
Messages: 896
Registered: May 2012
Location: Mesa, AZ
Karma: 3
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Senior Member |
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| George Beckman wrote on Wed, 10 April 2013 07:36 |
This is great news. I am not a big cat lover, but am willing to give the beast some credit.
Hopefully the coolant will stop seeping in with the head torqued a bit more and you can enjoy a nice extended trip. You have had your share of troubles with that engine.
Good to have learned abut the distributor cap being able to make that much noise. We all keep learning from these little events.
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Having a couple cats myownself, I'm betting the cat is the one that dislodged the distributor cap, just so it could take credit for whispering the fix to you. They'll do anything for a treat.
I once had an awful, howling noise coming from the my 2.0 liter Pinto motor. It was bad enough that I was thinking it was a main bearing or something else expensive. Finally traced it down to a lack of lubrication between the distributor lobe and the points.
You might want to take a close look at your distributor cap and rotor to make sure that the "knocking" didn't remove too much brass from the rotor or the individual cylinder tabs.
Mark Hickey
Mesa, AZ
1978 Royale Center Kitchen
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| Re: [GMCnet] Motor Knocking Part 2 [message #204280 is a reply to message #204185] |
Wed, 10 April 2013 13:24 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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Check your rotor for cracks. The main contact can break the plastic and swing to a retarded position. Good ending. Moral of story is 1st determine if engine speed or 1/2 speed noise to narrow the search abd then use a stethescope.
John Lebetski
Woodstock, IL
77 Eleganza II
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