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Leaking Coolant from Rockwell Intake [message #207086] Tue, 07 May 2013 16:03 Go to next message
Jon payne is currently offline  Jon payne   United States
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Registered: May 2008
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Senior Member
Hi all,

I just discovered that my newly installed (last year) Rockwell AL intake is leaking coolant on the LH aft corner. I am none to happy with the thought of removing the intake and replacing the gasket but I believe that is what needs to be done. I still need to check the torque but I am not too hopeful this will resolve the issue. This corner leaked closer to the top when I first installed the manifold and I increased the torque slightly and the leak stopped.

So I am asking the great minds here for suggestions to better seal this area when I replace the gasket. I am thinking to add Permatex (gray) to this area. The grey permatex is what I used to seal the ends of the manifold as can be seen in the below pic.

Any suggestions are most welcome.
Jon



http://www.gmcmhphotos.com/photos/data/6373/medium/IMG_0973.JPG


Jon Payne
76 Palm Beach
Westfield,IN
Re: Leaking Coolant from Rockwell Intake [message #207087 is a reply to message #207086] Tue, 07 May 2013 16:14 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
Senior Member
Jon, I can't speak to the Rockwell intake but I can to the possibility of antifreeze in the oil and the resulting damage to your engine. I'd send an oil sample off Asap.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207088 is a reply to message #207086] Tue, 07 May 2013 16:27 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Had a coolant leak on a Rockwell intake on the pass side rear. Turned out
to be a flaw in the casting. Jim K. shipped a new manifold freight prepaid.
Had it in two days. Used a Dick Paterson intake gasket on replacement with
permatex "High Tack"© Spray a gasket/sealant. Product number 80065.
Cleaned the surfaces with brake kleen. Inverted the manifold on the bench,
aligned gasket with bolts, let tack up overnight, just before assembly, use
"the right stuff" around the 4 water passages at the corners, and very
carefully lower into position on the neoprene end seals. a liberal dab of
"the right stuff" in the junction between the heads, block, and manifold,
screw all the fasteners in the holes by hand until the bolt heads contact
the manifold. using a hand operated ratchet or end wrench, tighten to about
15 foot pounds and check to see if the sealant oozes out the 4 corners. Do
not tighten beyond 25 foot pounds. NO PNEUMATIC TOOLS FOR INSTALLATION.
If everything is clean and flat you will not have leaks.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On May 7, 2013 2:03 PM, "Jon Payne" <embrep@sbcglobal.net> wrote:

>
>
> Hi all,
>
> I just discovered that my newly installed (last year) Rockwell AL intake
> is leaking coolant on the LH aft corner. I am none to happy with the
> thought of removing the intake and replacing the gasket but I believe that
> is what needs to be done. I still need to check the torque but I am not too
> hopeful this will resolve the issue. This corner leaked closer to the top
> when I first installed the manifold and I increased the torque slightly and
> the leak stopped.
>
> So I am asking the great minds here for suggestions to better seal this
> area when I replace the gasket. I am thinking to add Permatex (gray) to
> this area. The grey permatex is what I used to seal the ends of the
> manifold as can be seen in the below pic.
>
> Any suggestions are most welcome.
> Jon
>
>
>
>
> --
> Jon Payne
> 76 Palm Beach
> Westfield,IN
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207089 is a reply to message #207088] Tue, 07 May 2013 17:03 Go to previous messageGo to next message
Jon payne is currently offline  Jon payne   United States
Messages: 495
Registered: May 2008
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Senior Member
Thanks James for the info! Were you able to detect the flaw visually? My fear is that there is a flaw and I will have to pull the intake again.

Jon


Jon Payne
76 Palm Beach
Westfield,IN
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207090 is a reply to message #207089] Tue, 07 May 2013 17:20 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
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Senior Member
It leaked coolant between the head and manifold and dripped onto the
headers. Stinks like hot antifreeze. I could not see the flaw in the
casting without removing the manifold. It is thin where the fitting screws
into the manifold. The absolute last thing you want is antifreeze in your
lube oil. Put your big boy overalls on and pull the manifold. That is what
I would do. Several people that I know have had vacuum leaks and oil
pumping with the Rockwell. If it is installed like I mentioned, you should
not have problems. Several early Rockwells were quite narrow along the
bottom of the intake passages where it meets the cam and lifter galley. If
it leaks there, they will pump oil like mad. I would very carefully check
yours in this area. You can not have it too clean when you do this job. You
can tell by looking at the gasket if it was compressed and sealing
properly. Hope this helps.
Jim Hupy
Salem, Or
78 GMC Royale 403
On May 7, 2013 3:03 PM, "Jon Payne" <embrep@sbcglobal.net> wrote:

>
>
> Thanks James for the info! Were you able to detect the flaw visually? My
> fear is that there is a flaw and I will have to pull the intake again.
>
> Jon
> --
> Jon Payne
> 76 Palm Beach
> Westfield,IN
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: Leaking Coolant from Rockwell Intake [message #207114 is a reply to message #207086] Wed, 08 May 2013 01:05 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
N
Jon Payne wrote on Tue, 07 May 2013 14:03

Hi all,

So I am asking the great minds here for suggestions to better seal this area when I replace the gasket. I am thinking to add Permatex (gray) to this area. The grey permatex is what I used to seal the ends of the manifold as can be seen in the below pic.

Any suggestions are most welcome.
Jon



Jon,

Don't know if I am a great mind as mine was set 6 times, 5 by me and one by the engine rebuilder.
If you pull it...
I would get some plastigauge from you local parts store. .006 should do it. Dry set the manifold with plastigauge on the tops and bottoms of each port. It is tricky to tape little pieces on as you don't want to test with the tape thickness.. You don't have to torque to more than wrist tight and it should settle at 0.006 clearance everywhere. Even .010 would be good if it is fairly consistent. Dick Patterson gaskets are about .019 at crush... Maybe that was 0.017? Dick advised me to put block plates in even with no crossover.

Wipe everything down with lacquer thinner to remove any and all oiliness.

Then when you set it again, cut the heads off two bolts for the right side. Put slots in them. When you are ready to set it with gaskets and "Black RTV smeared on as thin as if you were putting it on a baby's bottom" (Great Dick Patterson quote) on both sides of the gaskets. Then set it on the bolt studs and swing (hinge) it down into position. Back the bolts out and start you torque. I would revisit in an bout an hour and in 24 hrs. If you can get to them, again after it has gotten warm once.

Are you using oil? I would look at the plugs and the intake ports on the head. If water is leaking I am not feeling confident. Failing 5 times can do that to you.

Change oil and have it tested was suggested and is good advise.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207115 is a reply to message #207114] Wed, 08 May 2013 04:25 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
great post George

folks need to get serious about this
''
gene



On Tue, May 7, 2013 at 11:05 PM, George Beckman <gbeckman@pggp.com> wrote:

>
>
> NJon Payne wrote on Tue, 07 May 2013 14:03
> > Hi all,
> >
> > So I am asking the great minds here for suggestions to better seal this
> area when I replace the gasket. I am thinking to add Permatex (gray) to
> this area. The grey permatex is what I used to seal the ends of the
> manifold as can be seen in the below pic.
> >
> > Any suggestions are most welcome.
> > Jon
>
>
> Jon,
>
> Don't know if I am a great mind as mine was set 6 times, 5 by me and one
> by the engine rebuilder.
> If you pull it...
> I would get some plastigauge from you local parts store. .006 should do
> it. Dry set the manifold with plastigauge on the tops and bottoms of each
> port. It is tricky to tape little pieces on as you don't want to test with
> the tape thickness.. You don't have to torque to more than wrist tight and
> it should settle at 0.006 clearance everywhere. Even .010 would be good if
> it is fairly consistent. Dick Patterson gaskets are about .019 at crush...
> Maybe that was 0.017? Dick advised me to put block plates in even with no
> crossover.
>
> Wipe everything down with lacquer thinner to remove any and all oiliness.
>
> Then when you set it again, cut the heads off two bolts for the right
> side. Put slots in them. When you are ready to set it with gaskets and
> "Black RTV smeared on as thin as if you were putting it on a baby's bottom"
> (Great Dick Patterson quote) on both sides of the gaskets. Then set it on
> the bolt studs and swing (hinge) it down into position. Back the bolts out
> and start you torque. I would revisit in an bout an hour and in 24 hrs. If
> you can get to them, again after it has gotten warm once.
>
> Are you using oil? I would look at the plugs and the intake ports on the
> head. If water is leaking I am not feeling confident. Failing 5 times can
> do that to you.
>
> Change oil and have it tested was suggested and is good advise.
>
> --
> '74 Eleganza, SE, Howell + EBL
> Best Wishes,
> George
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: Leaking Coolant from Rockwell Intake [message #207129 is a reply to message #207114] Wed, 08 May 2013 08:47 Go to previous messageGo to next message
Surbo is currently offline  Surbo   United States
Messages: 213
Registered: February 2004
Karma: 0
Senior Member
George Beckman wrote on Wed, 08 May 2013 01:05

N
Jon Payne wrote on Tue, 07 May 2013 14:03

Hi all,

So I am asking the great minds here for suggestions to better seal this area when I replace the gasket. I am thinking to add Permatex (gray) to this area. The grey permatex is what I used to seal the ends of the manifold as can be seen in the below pic.

Any suggestions are most welcome.
Jon



Jon,

Don't know if I am a great mind as mine was set 6 times, 5 by me and one by the engine rebuilder.
If you pull it...
I would get some plastigauge from you local parts store. .006 should do it. Dry set the manifold with plastigauge on the tops and bottoms of each port. It is tricky to tape little pieces on as you don't want to test with the tape thickness.. You don't have to torque to more than wrist tight and it should settle at 0.006 clearance everywhere. Even .010 would be good if it is fairly consistent. Dick Patterson gaskets are about .019 at crush... Maybe that was 0.017? Dick advised me to put block plates in even with no crossover.

Wipe everything down with lacquer thinner to remove any and all oiliness.

Then when you set it again, cut the heads off two bolts for the right side. Put slots in them. When you are ready to set it with gaskets and "Black RTV smeared on as thin as if you were putting it on a baby's bottom" (Great Dick Patterson quote) on both sides of the gaskets. Then set it on the bolt studs and swing (hinge) it down into position. Back the bolts out and start you torque. I would revisit in an bout an hour and in 24 hrs. If you can get to them, again after it has gotten warm once.

Are you using oil? I would look at the plugs and the intake ports on the head. If water is leaking I am not feeling confident. Failing 5 times can do that to you.

Change oil and have it tested was suggested and is good advise.



Fella's;

Follow George's suggestions, clean all surfaces with lacquer thinner THREE TIMES, RTV will not seal to an oily surface. Take a look at the FelPro gasket #1356, it will match the Rockwell intake very good. http://www.fme-cat.com/PartInterchange.aspx?pn=1356 Coat both sides of the gasket with black RTV, a little larger bead around the coolant passages.

Bob Drewes in SESD
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207130 is a reply to message #207089] Wed, 08 May 2013 08:56 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
Jon Payne wrote on Tue, 07 May 2013 15:03

Thanks James for the info! Were you able to detect the flaw visually? My fear is that there is a flaw and I will have to pull the intake again.

Jon


Bob Drewes comment reminded me of one other thing. Lay the gasket against the intake to make sure the ports are covered when the bolt holes are lined up. Double check the bottom (valley side) lips for coverage.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207138 is a reply to message #207129] Wed, 08 May 2013 10:10 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
G'day,

I'm sure BobD is correct when he notes that the Fel Pro gasket 1356 will match the ports in the Rockwell manifold quite well,
however, note that it is 0.060" thick.

Below is a link to the Jegs page listing a number of intake manifold gaskets:

http://tinyurl.com/cbvt3jm

http://www.jegs.com/webapp/wcs/stores/servlet/MkMdlYrSearchCmd?searchType=MkMdlYrSearch&Nty=0&catalogId=10002&Ne=1%2b2%2b3%2b13%2b11
47708%2b1147708&langId=-1&MODEL=1534710&storeId=10001&YEAR=1533564&MAKE=1534668&N=1534710+4294963296

Note that they are all 0.060" thick (no thickness provided for the Turkey Tray gasket)

It is my contention that while these gaskets work OK with OEM and other aluminum manifolds they don't work well with the Rockwell
manifold because they cause it to sit higher in the lifter valley.

I can't seem to find the thickness of the OEM turkey tray I am reasonably confident that is a lot thinner than 0.060". I suggest
that if you intend to fit a Rockwell manifold buy some gasket material that is 0.027 thick (I've got some) and make gaskets that fit
the Rockwell manifold perfectly and then "glue" them to the Rockwell manifold using Oxygen sensor compatible RTV.

Oxygen sensor compatible RTV should be used even if you have a carb on your engine, Who knows you (or the next owner) might want to
go to EFI setup and if you didn't use O2 compatible RTV you'll have to R&R the manifold.

Regards,
Rob M.
USAussie - Downunder


-----Original Message-----
From: Bob Drewes
Fella's;

Follow George's suggestions, clean all surfaces with lacquer thinner THREE TIMES, RTV will not seal to an oily surface. Take a look
at the FelPro gasket #1356, it will match the Rockwell intake very good. http://www.fme-cat.com/PartInterchange.aspx?pn=1356 Coat
both sides of the gasket with black RTV, a little larger bead around the coolant passages.

Bob

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207149 is a reply to message #207138] Wed, 08 May 2013 11:30 Go to previous messageGo to next message
Jon payne is currently offline  Jon payne   United States
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Registered: May 2008
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Senior Member
Thanks everyone for the advice. Just FYI, when I originally installed the Rockwell I used Dick Patterson gaskets with the block-off plates, glued the gasket to the intake using 3M weather strip adhesive, cut the heads off two bolts and used them as guide pins. Also applied thick bead of the Right Stuff gray RTV on the ends, waited unit the RTV skinned over then set the manifold. I don't recall putting any RTV around the coolant ports but can't be sure.

For manifold gaskets, I talked to JimK and he recommended a different gasket (http://appliedgmc.com/prod.itml/icOid/1256) Any thoughts on this gasket?

Jon


Jon Payne
76 Palm Beach
Westfield,IN
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207152 is a reply to message #207149] Wed, 08 May 2013 11:40 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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Registered: January 2011
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Senior Member
The Right Stuff Gray is a quick cute sealant. I believe the Ultra Gray is more oil resistant but the Ultra Black appears to have an even higher oil resistance.
I have always used Ultra black for that application

Emery Stora

On May 8, 2013, at 10:30 AM, Jon Payne <embrep@sbcglobal.net> wrote:

>
>
> Thanks everyone for the advice. Just FYI, when I originally installed the Rockwell I used Dick Patterson gaskets with the block-off plates, glued the gasket to the intake using 3M weather strip adhesive, cut the heads off two bolts and used them as guide pins. Also applied thick bead of the Right Stuff gray RTV on the ends, waited unit the RTV skinned over then set the manifold. I don't recall putting any RTV around the coolant ports but can't be sure.
>
> For manifold gaskets, I talked to JimK and he recommended a different gasket (http://appliedgmc.com/prod.itml/icOid/1256) Any thoughts on this gasket?
>
> Jon
>
> --
> Jon Payne
> 76 Palm Beach
> Westfield,IN
> _______________________________________________
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Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207157 is a reply to message #207152] Wed, 08 May 2013 12:00 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Senior Member
Emery, you are spot on about the grey stuff. Gotta' work too fast for
accuracy with it. I should have said Ultra black, slower cure rate with it.
Jim Hupy
On May 8, 2013 9:40 AM, "Emery Stora" <emerystora@me.com> wrote:

> The Right Stuff Gray is a quick cute sealant. I believe the Ultra Gray is
> more oil resistant but the Ultra Black appears to have an even higher oil
> resistance.
> I have always used Ultra black for that application
>
> Emery Stora
>
> On May 8, 2013, at 10:30 AM, Jon Payne <embrep@sbcglobal.net> wrote:
>
> >
> >
> > Thanks everyone for the advice. Just FYI, when I originally installed
> the Rockwell I used Dick Patterson gaskets with the block-off plates, glued
> the gasket to the intake using 3M weather strip adhesive, cut the heads off
> two bolts and used them as guide pins. Also applied thick bead of the Right
> Stuff gray RTV on the ends, waited unit the RTV skinned over then set the
> manifold. I don't recall putting any RTV around the coolant ports but
> can't be sure.
> >
> > For manifold gaskets, I talked to JimK and he recommended a different
> gasket (http://appliedgmc.com/prod.itml/icOid/1256) Any thoughts on this
> gasket?
> >
> > Jon
> >
> > --
> > Jon Payne
> > 76 Palm Beach
> > Westfield,IN
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
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Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207159 is a reply to message #207157] Wed, 08 May 2013 13:07 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Location: Sydney, Australia
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Senior Member
Jim,

The Ultra black (Oxygen sensor compatible) in the pressurized can makes it REAL easy to get a nice even bead on the front and back!

WARNING - whatever RTV you use make absolutely sure it is Oxygen sensor compatible!!

Regards,
Rob M.

-----Original Message-----
From: James Hupy

Emery, you are spot on about the grey stuff. Gotta' work too fast for
accuracy with it. I should have said Ultra black, slower cure rate with it.
Jim Hupy

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207267 is a reply to message #207149] Thu, 09 May 2013 16:30 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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Jon Payne wrote on Wed, 08 May 2013 09:30



For manifold gaskets, I talked to JimK and he recommended a different gasket (http://appliedgmc.com/prod.itml/icOid/1256) Any thoughts on this gasket?

Jon


I guess I forgot the gasket list. Let's see... First Dick's with black RTV followed but the very thick Suggested by BobDrewes in his above post with RTV, followed by a turkey tray when the engine was rebuilt ( different block and heads) followed by what looked like the one JimK is suggesting.. Not quite as thick as the very thick gasket using Right Stuff followed with that gasket again using 3m sealer, followed by a different Rockwell and Dick's gaskets using RTV. I am even getting good at the silly AC bracket.

If the manifold dry seats to 0.006 or at least evenly under 0.012 and the ports are aligned when the bolt holes are aligned,I think the Patterson gaskets will be thick enough. I had big troubles getting ports covered. Even the turkey tray did not have the bead mashed on the bottom of some ports. I had to wallow the bolt holes out to get the gaskets to cover the bottom of the ports.

The first one I was not imagining the alignment problem and used 8 quarts in 400 miles. I had daylight on #8 intake between gasket and intake. We were so focused on making sure the intake was sitting on the heads evenly we just did look at the port coverage. I thought if the gasket was on the bolt holes it was good. Like Bob Dreaes says, check everything three times. It was the "everything" that got me on that first try.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207269 is a reply to message #207267] Thu, 09 May 2013 17:03 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Senior Member
George, me too.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On May 9, 2013 2:30 PM, "George Beckman" <gbeckman@pggp.com> wrote:

>
>
> Jon Payne wrote on Wed, 08 May 2013 09:30
> > For manifold gaskets, I talked to JimK and he recommended a different
> gasket (http://appliedgmc.com/prod.itml/icOid/1256) Any thoughts on this
> gasket?
> >
> > Jon
>
> I guess I forgot the gasket list. Let's see... First Dick's with black
> RTV followed but the very thick Suggested by BobDrewes in his above post
> with RTV, followed by a turkey tray when the engine was rebuilt ( different
> block and heads) followed by what looked like the one JimK is suggesting..
> Not quite as thick as the very thick gasket using Right Stuff followed with
> that gasket again using 3m sealer, followed by a different Rockwell and
> Dick's gaskets using RTV. I am even getting good at the silly AC bracket.
>
> If the manifold dry seats to 0.006 or at least evenly under 0.012 and the
> ports are aligned when the bolt holes are aligned,I think the Patterson
> gaskets will be thick enough. I had big troubles getting ports covered.
> Even the turkey tray did not have the bead mashed on the bottom of some
> ports. I had to wallow the bolt holes out to get the gaskets to cover the
> bottom of the ports.
>
> The first one I was not imagining the alignment problem and used 8 quarts
> in 400 miles. I had daylight on #8 intake between gasket and intake. We
> were so focused on making sure the intake was sitting on the heads evenly
> we just did look at the port coverage. I thought if the gasket was on the
> bolt holes it was good. Like Bob Dreaes says, check everything three times.
> It was the "everything" that got me on that first try.
> --
> '74 Eleganza, SE, Howell + EBL
> Best Wishes,
> George
> _______________________________________________
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Re: Leaking Coolant from Rockwell Intake [message #207278 is a reply to message #207086] Thu, 09 May 2013 19:02 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
Senior Member
I'm thinking this is what caused my engine failure. My coolant is brown, my oil thin. Have not sent it to blackstone yet.

Not really happy with an "upgrade" causing a total catastrophic failure. Should have lived with the old intake and it's crack.

There are a few other "Upgrades" I have been talked into around here that I'd rather have saved my $$ on.

Sometimes there is no substitute for engineering backed by a 100 year old company. Then again, sometimes there is.

Live and learn...

Sad


-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: [GMCnet] Leaking Coolant from Rockwell Intake [message #207299 is a reply to message #207278] Fri, 10 May 2013 06:31 Go to previous messageGo to next message
Jim Bounds is currently offline  Jim Bounds   United States
Messages: 842
Registered: January 2004
Karma: 0
Senior Member
First Chris, I'm sorry that has happened.  I have found from building piles of motors, doing brake jobs, suspension rebuilds, fuel system rebuilds-- on and on that every deviation from the accepted will always come with unexpected results and engineering incompatibilities.  Any time you change one thing there are reprocussions and many of them can put you in harms way.  Of course not accepting the progress is good is not good but you must use several filters to make decisions on changes.  It's not fair to say any change will cause problems but it's also not good to not be careful in your modification selection.
 
To date, we have had 100% satisfaction on installing blockoff plates (not filling the crossover with zinc alloy), cleaning and having the original intake magnafluxed the installing it with a fiber gasket and electric choke on the carb.  We have installed Rockwell intakes but you have to be very careful and aware of fit in using them.  We dry fit them expecting there will be tweeks, if you do this and are very careful the intakes work well.  Is it an earthshaking difference in performance--- no.  It is though very cool and if you take the time and diligence you can have a good running motor with that intake.  If your intake is really cracked up, it is the option but if there is only the 1 crack (almost every original intake has this) between the secondary ports on the topside of the intake-- it can be fixed reliably and reused.
 
It may or may not be the reason for the motor failure, I would not even try and figure out what happened-- old motors have the right to just stop working!  You must realize this and just roll with it if you expect to have any hair on your head left.  "It Happens" as Forest says, the best you can do is pay attention to the details and just keep moving.  Good luck on your new motor...
 
Jim Bounds
--------------------


________________________________
From: Chris Choffat <cchoffataz@yahoo.com>
To: gmclist@temp.gmcnet.org
Sent: Thursday, May 9, 2013 8:02 PM
Subject: Re: [GMCnet] Leaking Coolant from Rockwell Intake




I'm thinking this is what caused my engine failure. My coolant is brown, my oil thin. Have not sent it to blackstone yet.

Not really happy with an "upgrade" causing a total catastrophic failure. Should have lived with the old intake and it's crack.

There are a few other "Upgrades" I have been talked into around here that I'd rather have saved my $$ on.

Sometimes there is no substitute for engineering backed by a 100 year old company. Then again, sometimes there is.

Live and learn...

:(
--
-Chr$: Perpetual SmartAss
Scottsdale, AZ
77 Ex-Kingsley Featuring:  455,  Power Drive, 3:21, Rockwell, Jim B QJET, Qbag. Now for Sale
2010 Nomad 24 Ft Travel Trailer

Photosite: Chrisc "It has Begun"
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Re: Leaking Coolant from Rockwell Intake [message #207322 is a reply to message #207086] Fri, 10 May 2013 10:24 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
Senior Member
Yep the old one has that usual crack. Shoulda lived with it. Could still bark the tires with that.

The rockwell got such glowing reviews here so I went with it. Then the problems started to be discussed here. It dry fit fine. Didn't have any gaps from what I could tell with a feeler, but sumptin aint right. The first time I set it I had Oil out the back of the motor. The second time, well, you know.

I dodged a bullet with the "Dual Bag" system as I waited. Wish I waited a bit longer and just either gotten regular bags or the ones from Dan in AJ. I preferred the ride with the original setup.

Wondering what will come up with some of the larger newer upgrades like the 1-ton and the reaction arm.

Then there are a few odds and ends that haven't been a problem, but were a waste of $$. I'll not bother to list those.

Your carb works well. I have not even connected the electric choke. Don't really need it here.



-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: Leaking Coolant from Rockwell Intake [message #207360 is a reply to message #207278] Fri, 10 May 2013 23:17 Go to previous messageGo to previous message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
Chr$ wrote on Thu, 09 May 2013 18:02

I'm thinking this is what caused my engine failure. My coolant is brown, my oil thin. Have not sent it to blackstone yet.

Not really happy with an "upgrade" causing a total catastrophic failure. Should have lived with the old intake and it's crack.

There are a few other "Upgrades" I have been talked into around here that I'd rather have saved my $$ on.

Sometimes there is no substitute for engineering backed by a 100 year old company. Then again, sometimes there is.

Live and learn...

Sad

Chris--you are so right on this one. This net steers people into areas that may be great for classic car nuts but frankly it is not that great for poeple who want to enjoy their coaches.


Bob de Kruyff
78 Eleganza
Chandler, AZ
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