Home » Public Forums » GMCnet » [GMCnet] Fw: Intake Manifold Question
| [GMCnet] Fw: Intake Manifold Question [message #158742] |
Tue, 31 January 2012 14:57  |
ejuk8em
Messages: 90
Registered: July 2010
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Hi all,
While in winter hibernation here in Illinois (although it has been over 50 degrees for the last couple of days) I pulled the carb off of The Stray Dog to have it rebuilt. I just spoke with the repair shop and they mentioned that the pre-heat choke was packed full of carbon from the engine. They are suggesting that I pull the intake and check/replace the intake manifold heat tube, as it is likely damaged or rusted. Has anyone had this happen? If so, I could use a bit of instruction on what to look for and where to get this part. I'm also wondering if I need to be doing anything else while the intake is off. I've read the thread on blocking off the exhaust passenges and I think this would certainly be the time to do that.
Any suggestions would be appreciated.
Thanks,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158745 is a reply to message #158742] |
Tue, 31 January 2012 15:33  |
sgltrac
Messages: 2797
Registered: April 2011
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Applied gmc sells what you seek. Go to their website. www.appliedgmc.com.
Sully
77 royale
Sent from my Verizon Wireless BlackBerry
-----Original Message-----
From: "Lyle A. Rigdon" <ejuk8em@yahoo.com>
Sender: gmclist-bounces@temp.gmcnet.org
Date: Tue, 31 Jan 2012 12:57:41
To: GMC List Serv<gmclist@temp.gmcnet.org>
Reply-To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Fw: Intake Manifold Question
Hi all,
While in winter hibernation here in Illinois (although it has been over 50 degrees for the last couple of days) I pulled the carb off of The Stray Dog to have it rebuilt. I just spoke with the repair shop and they mentioned that the pre-heat choke was packed full of carbon from the engine. They are suggesting that I pull the intake and check/replace the intake manifold heat tube, as it is likely damaged or rusted. Has anyone had this happen? If so, I could use a bit of instruction on what to look for and where to get this part. I'm also wondering if I need to be doing anything else while the intake is off. I've read the thread on blocking off the exhaust passenges and I think this would certainly be the time to do that.
Any suggestions would be appreciated.
Thanks,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
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Sully
77 Royale basket case.
Future motorhome land speed record holder(bucket list)
Seattle, Wa.
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158750 is a reply to message #158742] |
Tue, 31 January 2012 16:00 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
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Lyle,
You do not need to remove the intake manifold to replace the heat tube.
It's bolted into the manifold with two bolts -- right where the tube from
the choke is connected.
If you do remove the manifold, IMHO you should block the crossover. Doing
that will disable the heat tube, isolating it from the exhaust gases. Then
you'll have to either get choke heat from a tube wrapped around an exhaust
manifold or, preferably, install an electric choke.
Ken H.
On Tue, Jan 31, 2012 at 3:57 PM, Lyle A. Rigdon wrote:
> ...I just spoke with the repair shop and they mentioned that the pre-heat
> choke was packed full of carbon from the engine. They are suggesting that I
> pull the intake and check/replace the intake manifold heat tube, as it is
> likely damaged or rusted...
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www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158764 is a reply to message #158750] |
Tue, 31 January 2012 17:02 |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Lyle,
I agree with Ken, however, when you (or the shop) pulls the manifold off it is quite possible that it is cracked so when you do the
job make sure you have plenty of time to find a good manifold.
Regards,
Rob M.
-----Original Message-----
From: Ken Henderson
Lyle,
You do not need to remove the intake manifold to replace the heat tube.
It's bolted into the manifold with two bolts -- right where the tube from
the choke is connected.
If you do remove the manifold, IMHO you should block the crossover. Doing
that will disable the heat tube, isolating it from the exhaust gases. Then
you'll have to either get choke heat from a tube wrapped around an exhaust
manifold or, preferably, install an electric choke.
Ken H.
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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
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158783 is a reply to message #158742] |
Tue, 31 January 2012 18:21 |
Gary Worobec
Messages: 867
Registered: May 2005
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Just a word of caution.....If you do replace the manifold heat choke make
sure they are very careful about the gasket material used to seal the flange
to the manifold. There is a lot of exhaust gas pressure there and on my
coach and several others I know of the gasket blew out and melted the wiring
that runs down the right rocker cover. I used a piece of Remflex and it was
good until I swapped out the manifold with the aluminum one from Rockwell.
Thanks
Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA
----- Original Message -----
From: "Lyle A. Rigdon" <ejuk8em@yahoo.com>
To: "GMC List Serv" <gmclist@temp.gmcnet.org>
Sent: Tuesday, January 31, 2012 12:57 PM
Subject: [GMCnet] Fw: Intake Manifold Question
Hi all,
While in winter hibernation here in Illinois (although it has been over 50
degrees for the last couple of days) I pulled the carb off of The Stray Dog
to have it rebuilt. I just spoke with the repair shop and they mentioned
that the pre-heat choke was packed full of carbon from the engine. They are
suggesting that I pull the intake and check/replace the intake manifold heat
tube, as it is likely damaged or rusted. Has anyone had this happen? If so,
I could use a bit of instruction on what to look for and where to get this
part. I'm also wondering if I need to be doing anything else while the
intake is off. I've read the thread on blocking off the exhaust passenges
and I think this would certainly be the time to do that.
Any suggestions would be appreciated.
Thanks,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158823 is a reply to message #158783] |
Wed, 01 February 2012 00:32 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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I can't help but feel they are trying to find extra work to do on your coach.
On Tue, Jan 31, 2012 at 4:21 PM, Gary Worobec <gtw5@earthlink.net> wrote:
> Just a word of caution.....If you do replace the manifold heat choke make
> sure they are very careful about the gasket material used to seal the flange
> to the manifold. There is a lot of exhaust gas pressure there and on my
> coach and several others I know of the gasket blew out and melted the wiring
> that runs down the right rocker cover. I used a piece of Remflex and it was
> good until I swapped out the manifold with the aluminum one from Rockwell.
>
> Thanks
>
> Gary and Joanne Worobec
> 1973 GMC Glacier
> Anza, CA
>
>
>
>
> ----- Original Message -----
> From: "Lyle A. Rigdon" <ejuk8em@yahoo.com>
> To: "GMC List Serv" <gmclist@temp.gmcnet.org>
> Sent: Tuesday, January 31, 2012 12:57 PM
> Subject: [GMCnet] Fw: Intake Manifold Question
>
>
>
>
>
>
>
>
>
>
>
>
> Hi all,
> While in winter hibernation here in Illinois (although it has been over 50
> degrees for the last couple of days) I pulled the carb off of The Stray Dog
> to have it rebuilt. I just spoke with the repair shop and they mentioned
> that the pre-heat choke was packed full of carbon from the engine. They are
> suggesting that I pull the intake and check/replace the intake manifold heat
> tube, as it is likely damaged or rusted. Has anyone had this happen? If so,
> I could use a bit of instruction on what to look for and where to get this
> part. I'm also wondering if I need to be doing anything else while the
> intake is off. I've read the thread on blocking off the exhaust passenges
> and I think this would certainly be the time to do that.
> Any suggestions would be appreciated.
> Thanks,
> Lyle
>
> Lyle A. Rigdon, Retired Superintendent
> '73 Pineapple Yellow Sequoia - The Stray Dog
> Pawnee, IL 62558
> Pawnee Pride - Live It!
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _______________________________________________
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> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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1-800-752-7502
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158826 is a reply to message #158742] |
Wed, 01 February 2012 01:19 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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| ejuk8em wrote on Tue, 31 January 2012 14:57 |
Hi all,
While in winter hibernation here in Illinois (although it has been over 50 degrees for the last couple of days) I pulled the carb off of The Stray Dog to have it rebuilt. I just spoke with the repair shop and they mentioned that the pre-heat choke was packed full of carbon from the engine. They are suggesting that I pull the intake and check/replace the intake manifold heat tube, as it is likely damaged or rusted. Has anyone had this happen? If so, I could use a bit of instruction on what to look for and where to get this part. I'm also wondering if I need to be doing anything else while the intake is off. I've read the thread on blocking off the exhaust passenges and I think this would certainly be the time to do that.
Any suggestions would be appreciated.
Thanks,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
|
What kind of BS is this? The choke tube is held in with 2 bolts and takes about 15 minutes to replace. Make sure Jim sends you a new gasket with it. I pretty sure the tube comes with a gasket. When you pull the tube you are looking for obvious rusting through the tube causing it to leak exhaust into the tube.
Here is the part from Jim Kanomata (Applied GMC).
http://www.appliedgmc.com/prod.itml/icOid/805
If it is one of the other two heater tubes, Jim K. also has them:
http://www.appliedgmc.com/prod.itml/icOid/803
http://www.appliedgmc.com/prod.itml/icOid/804
It should not be the above two tubes because if they were leaking they would not pull exhaust (and carbon) into the choke assembly.
Someone is trying to take advantage of you by wanting to pull the intake manifold.
Call Jim K. and talk to him.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158852 is a reply to message #158826] |
Wed, 01 February 2012 10:01 |
ejuk8em
Messages: 90
Registered: July 2010
Karma: 0
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Member |
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Hi All,
Wow... I certainly didn't mean to set off such an intense debate. Let me say up front that I do have confidence in the shop that has the carb. They have done previous work for us on other vehicles (Corvair) and have always been top notch and very upfront with what was needed and what they were doing. Members of the local Corvair club use them for anything GM.. not just our little 'Vairs. I have never, ever heard anyone speak unkindly about their work. Could they be mistaken? Sure, we all can be from time to time. Would they be up to some skulduggery..? Never.
When I spoke with them about rebuilding the carb for the GMC, they seemed to understand - without any prompting - that it was going to require a different rebuild than the Q-jet from your typical Toronado. However, even though they have extensive GM experience, they are not GMC folks and that is exactly why I turned to this group for advice.
The way they explained the heat tube to me is that it runs through the intake and the only way to replace it is to remove the intake to get at it. I have not pulled the choke housing to see if it just has the short "loop" pipe that can be gotten at by removing the two bolts mounting it to the intake. I will try to do that this evening or tomorrow and will report back to the group.
Please do know how much I appreciate everyone's input here. I am NOT an engine guy, but can wobble along fairly well with reasonably clear instructions.
Regards,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
--- On Wed, 2/1/12, Ken Burton <n9cv@comcast.net> wrote:
From: Ken Burton <n9cv@comcast.net>
Subject: Re: [GMCnet] Fw: Intake Manifold Question
To: gmclist@temp.gmcnet.org
Date: Wednesday, February 1, 2012, 1:19 AM
ejuk8em wrote on Tue, 31 January 2012 14:57
> Hi all,
> While in winter hibernation here in Illinois (although it has been over 50 degrees for the last couple of days) I pulled the carb off of The Stray Dog to have it rebuilt. I just spoke with the repair shop and they mentioned that the pre-heat choke was packed full of carbon from the engine. They are suggesting that I pull the intake and check/replace the intake manifold heat tube, as it is likely damaged or rusted. Has anyone had this happen? If so, I could use a bit of instruction on what to look for and where to get this part. I'm also wondering if I need to be doing anything else while the intake is off. I've read the thread on blocking off the exhaust passenges and I think this would certainly be the time to do that.
> Any suggestions would be appreciated.
> Thanks,
> Lyle
>
> Lyle A. Rigdon, Retired Superintendent
> '73 Pineapple Yellow Sequoia - The Stray Dog
> Pawnee, IL 62558
> Pawnee Pride - Live It!
What kind of BS is this? The choke tube is held in with 2 bolts and takes about 15 minutes to replace. Make sure Jim sends you a new gasket with it. I pretty sure the tube comes with a gasket. When you pull the tube you are looking for obvious rusting through the tube causing it to leak exhaust into the tube.
Here is the part from Jim Kanomata (Applied GMC).
http://www.appliedgmc.com/prod.itml/icOid/805
If it is one of the other two heater tubes, Jim K. also has them:
http://www.appliedgmc.com/prod.itml/icOid/803
http://www.appliedgmc.com/prod.itml/icOid/804
It should not be the above two tubes because if they were leaking they would not pull exhaust (and carbon) into the choke assembly.
Someone is trying to take advantage of you by wanting to pull the intake manifold.
Call Jim K. and talk to him.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158854 is a reply to message #158852] |
Wed, 01 February 2012 10:16 |
Gary Worobec
Messages: 867
Registered: May 2005
Karma: -1
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Senior Member |
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Lyle, you just have to pull the two bolts on the flange and the loop comes
out. You don't have to remove the manifold.
Thanks
Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA
----- Original Message -----
From: "Lyle A. Rigdon" <ejuk8em@yahoo.com>
To: <gmclist@temp.gmcnet.org>
Sent: Wednesday, February 01, 2012 8:01 AM
Subject: Re: [GMCnet] Fw: Intake Manifold Question
Hi All,
Wow... I certainly didn't mean to set off such an intense debate. Let me say
up front that I do have confidence in the shop that has the carb. They have
done previous work for us on other vehicles (Corvair) and have always been
top notch and very upfront with what was needed and what they were doing.
Members of the local Corvair club use them for anything GM.. not just our
little 'Vairs. I have never, ever heard anyone speak unkindly about their
work. Could they be mistaken? Sure, we all can be from time to time. Would
they be up to some skulduggery..? Never.
When I spoke with them about rebuilding the carb for the GMC, they seemed to
understand - without any prompting - that it was going to require a
different rebuild than the Q-jet from your typical Toronado. However, even
though they have extensive GM experience, they are not GMC folks and that is
exactly why I turned to this group for advice.
The way they explained the heat tube to me is that it runs through the
intake and the only way to replace it is to remove the intake to get at it.
I have not pulled the choke housing to see if it just has the short "loop"
pipe that can be gotten at by removing the two bolts mounting it to the
intake. I will try to do that this evening or tomorrow and will report back
to the group.
Please do know how much I appreciate everyone's input here. I am NOT an
engine guy, but can wobble along fairly well with reasonably clear
instructions.
Regards,
Lyle
Lyle A. Rigdon, Retired Superintendent
'73 Pineapple Yellow Sequoia - The Stray Dog
Pawnee, IL 62558
Pawnee Pride - Live It!
--- On Wed, 2/1/12, Ken Burton <n9cv@comcast.net> wrote:
From: Ken Burton <n9cv@comcast.net>
Subject: Re: [GMCnet] Fw: Intake Manifold Question
To: gmclist@temp.gmcnet.org
Date: Wednesday, February 1, 2012, 1:19 AM
ejuk8em wrote on Tue, 31 January 2012 14:57
> Hi all,
> While in winter hibernation here in Illinois (although it has been over 50
> degrees for the last couple of days) I pulled the carb off of The Stray
> Dog to have it rebuilt. I just spoke with the repair shop and they
> mentioned that the pre-heat choke was packed full of carbon from the
> engine. They are suggesting that I pull the intake and check/replace the
> intake manifold heat tube, as it is likely damaged or rusted. Has anyone
> had this happen? If so, I could use a bit of instruction on what to look
> for and where to get this part. I'm also wondering if I need to be doing
> anything else while the intake is off. I've read the thread on blocking
> off the exhaust passenges and I think this would certainly be the time to
> do that.
> Any suggestions would be appreciated.
> Thanks,
> Lyle
>
> Lyle A. Rigdon, Retired Superintendent
> '73 Pineapple Yellow Sequoia - The Stray Dog
> Pawnee, IL 62558
> Pawnee Pride - Live It!
What kind of BS is this? The choke tube is held in with 2 bolts and takes
about 15 minutes to replace. Make sure Jim sends you a new gasket with it. I
pretty sure the tube comes with a gasket. When you pull the tube you are
looking for obvious rusting through the tube causing it to leak exhaust into
the tube.
Here is the part from Jim Kanomata (Applied GMC).
http://www.appliedgmc.com/prod.itml/icOid/805
If it is one of the other two heater tubes, Jim K. also has them:
http://www.appliedgmc.com/prod.itml/icOid/803
http://www.appliedgmc.com/prod.itml/icOid/804
It should not be the above two tubes because if they were leaking they would
not pull exhaust (and carbon) into the choke assembly.
Someone is trying to take advantage of you by wanting to pull the intake
manifold.
Call Jim K. and talk to him.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158861 is a reply to message #158854] |
Wed, 01 February 2012 11:22 |
Dennis S
Messages: 3046
Registered: November 2005
Karma: 2
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Senior Member |
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In fairness to the shop that may be expected to replace the choke heater tube -- yes, it is only held in by two bolts -- but if they are rusted tight, break off or are already broken off, or who knows what else -- it may require drilling out the old, retapping and such -- all of which adds to the time to do a simple exhange. And if it has been leaking around that area the mounting surface may be erroded and perhsp only a Remflex material is thick enough to use as a gasket.
Just some thoughts --lots of simple projects can be more time consuming than we first expect -- and it is worse if we are paying to have it done and have vastly different expectations of the $ cost versus the actual bill.
Dennis
Dennis S
73 Painted Desert 230
Memphis TN Metro
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158864 is a reply to message #158742] |
Wed, 01 February 2012 11:48 |
sgltrac
Messages: 2797
Registered: April 2011
Karma: 1
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Senior Member |
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Maybe they think the crossover is cracked and are being misunderstood?
Sully
77 royale
------Original Message------
From: Dennis Sexton
Sender: gmclist-bounces@temp.gmcnet.org
To: gmclist@temp.gmcnet.org
ReplyTo: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Fw: Intake Manifold Question
Sent: Feb 1, 2012 9:22 AM
In fairness to the shop that may be expected to replace the choke heater tube -- yes, it is only held in by two bolts -- but if they are rusted tight, break off or are already broken off, or who knows what else -- it may require drilling out the old, retapping and such -- all of which adds to the time to do a simple exhange. And if it has been leaking around that area the mounting surface may be erroded and perhsp only a Remflex material is thick enough to use as a gasket.
Just some thoughts --lots of simple projects can be more time consuming than we first expect -- and it is worse if we are paying to have it done and have vastly different expectations of the $ cost versus the actual bill.
Dennis
--
Dennis S
73 Painted Desert 230
Germantown, TN
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Sully
77 Royale basket case.
Future motorhome land speed record holder(bucket list)
Seattle, Wa.
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158867 is a reply to message #158852] |
Wed, 01 February 2012 12:02 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Senior Member |
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Lyle, on many GM manifolds, the heat riser passage is a finger sized orfice
that only gives carb and choke stove preheat. They frequently do become
plugged with carbon on high mileage engines, or those that see infrequent
oil changes. The Oldsmobile manifolds have a passage that is the size of an
exhaust port, and exhaust gasses exchange through it. I have not ever seen
one that was plugged with carbon, but almost always the bottom of the
manifold is caked with burned on oil residue, particularly if the turkey
tray type intake manifold gasket has been swapped out. The bottom of the
heat riser passage is most frequently cracked because of the high heat that
the motorhome use presents. If the cracks extend into the floor of the
intake runners, the engine will run like crap, and will have a poor idle.
If your engine is exhibiting the symptoms that I have described, make sure
that your Mechanic shines a strong light into the manifold when the carb is
off and look carefully for cracks. If they are found, it is my strong
suggestion to replace the intake manifold, either with a known good used
one from a Motorhome or a Toronado, or the new Rockwell aluminum manifold.
What ever you find, they are not likely to be very cheap. Hope this helps
clarify the issue.
Jim Hupy
Salem, OR
78 GMC Royale 403
On Wed, Feb 1, 2012 at 8:01 AM, Lyle A. Rigdon <ejuk8em@yahoo.com> wrote:
> Hi All,
> Wow... I certainly didn't mean to set off such an intense debate. Let me
> say up front that I do have confidence in the shop that has the carb. They
> have done previous work for us on other vehicles (Corvair) and have
> always been top notch and very upfront with what was needed and what they
> were doing. Members of the local Corvair club use them for anything GM..
> not just our little 'Vairs. I have never, ever heard anyone speak unkindly
> about their work. Could they be mistaken? Sure, we all can be from time to
> time. Would they be up to some skulduggery..? Never.
>
> When I spoke with them about rebuilding the carb for the GMC, they seemed
> to understand - without any prompting - that it was going to require
> a different rebuild than the Q-jet from your typical Toronado. However,
> even though they have extensive GM experience, they are not GMC folks and
> that is exactly why I turned to this group for advice.
>
> The way they explained the heat tube to me is that it runs through the
> intake and the only way to replace it is to remove the intake to get at it.
> I have not pulled the choke housing to see if it just has the short "loop"
> pipe that can be gotten at by removing the two bolts mounting it to the
> intake. I will try to do that this evening or tomorrow and will report back
> to the group.
>
> Please do know how much I appreciate everyone's input here. I am NOT an
> engine guy, but can wobble along fairly well with reasonably clear
> instructions.
> Regards,
> Lyle
>
> Lyle A. Rigdon, Retired Superintendent
> '73 Pineapple Yellow Sequoia - The Stray Dog
> Pawnee, IL 62558
> Pawnee Pride - Live It!
>
> --- On Wed, 2/1/12, Ken Burton <n9cv@comcast.net> wrote:
>
>
> From: Ken Burton <n9cv@comcast.net>
> Subject: Re: [GMCnet] Fw: Intake Manifold Question
> To: gmclist@temp.gmcnet.org
> Date: Wednesday, February 1, 2012, 1:19 AM
>
>
>
>
> ejuk8em wrote on Tue, 31 January 2012 14:57
> > Hi all,
> > While in winter hibernation here in Illinois (although it has been over
> 50 degrees for the last couple of days) I pulled the carb off of The Stray
> Dog to have it rebuilt. I just spoke with the repair shop and they
> mentioned that the pre-heat choke was packed full of carbon from the
> engine. They are suggesting that I pull the intake and check/replace the
> intake manifold heat tube, as it is likely damaged or rusted. Has anyone
> had this happen? If so, I could use a bit of instruction on what to look
> for and where to get this part. I'm also wondering if I need to be doing
> anything else while the intake is off. I've read the thread on blocking off
> the exhaust passenges and I think this would certainly be the time to do
> that.
> > Any suggestions would be appreciated.
> > Thanks,
> > Lyle
> >
> > Lyle A. Rigdon, Retired Superintendent
> > '73 Pineapple Yellow Sequoia - The Stray Dog
> > Pawnee, IL 62558
> > Pawnee Pride - Live It!
>
> What kind of BS is this? The choke tube is held in with 2 bolts and takes
> about 15 minutes to replace. Make sure Jim sends you a new gasket with
> it. I pretty sure the tube comes with a gasket. When you pull the tube
> you are looking for obvious rusting through the tube causing it to leak
> exhaust into the tube.
>
> Here is the part from Jim Kanomata (Applied GMC).
>
> http://www.appliedgmc.com/prod.itml/icOid/805
>
> If it is one of the other two heater tubes, Jim K. also has them:
> http://www.appliedgmc.com/prod.itml/icOid/803
> http://www.appliedgmc.com/prod.itml/icOid/804
>
> It should not be the above two tubes because if they were leaking they
> would not pull exhaust (and carbon) into the choke assembly.
>
> Someone is trying to take advantage of you by wanting to pull the intake
> manifold.
>
> Call Jim K. and talk to him.
>
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158880 is a reply to message #158861] |
Wed, 01 February 2012 14:42 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
If this is an experienced shop they will try to remove the bolts WITHOUT breaking them. If the bolts are stuck, which I have never heard of on the heater, an experienced shop will soak them with Kroil or something similar to Kroil and hit them with a 3/8" drive battery powered impact to remove them.
Removing the manifold adds nothing when replacing the heater other than added expense and added billable time. I still say these people are scamming you are have no idea what they are doing.
This is an example of taking 15 minute job and making it into at least a 4 hour billable project.
I would go back and ask again why they want to remove the manifold. If they insist pulling the manifold go somewhere else.
If you decide to let them pull the manifold then have them install the crossover blocking plates (available for Jim K) and an electric choke (also available from Jim K).
Side note: When I removed my heater I used stainless bolts which are available from any hardware store to install the blocking plate. It really was not necessary but why not use them as I already had them around.
Call Jim K. at Applied GMC and talk to him. 1-800-752-7502
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Fw: Intake Manifold Question [message #158889 is a reply to message #158852] |
Wed, 01 February 2012 16:29 |
|
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
|
Senior Member |
|
|
Lyle,
Some real smart guy once said "a picture is worth a thousand words" so here you go:
http://www.appliedgmc.com/prod.itml/icOid/805
I assume that your mechanic will realize that the bolts that retain the existing choke stove will be rusted in solid and a real
bitch to get out without shearing them and spray them with a penetrating fluid for a couple of days before he tries to remove them.
As far as the carb goes, personally I would NOT trust anyone except Dick Paterson to rebuild it.
http://www.paterson-gmc.com/gmc-motorhome/carburation/
Also you might want to consider having Dick re-build / re-curve your distributor:
http://www.paterson-gmc.com/street-strip-hot-rod/ignition/
I installed these two items from Dick on my GMC and COULD NOT BELIEVE how much better it ran, it was like day and night or as we say
Downunder "chalk and cheese!" Give Dick a call I GA-RON-TEE it will be worth the price of a phone call!
If when the mechanic removes the carb and checks the intake manifold for cracks if it is NOT cracked the crossover can be blocked
with this kit:
http://www.appliedgmc.com/prod.itml/icOid/799
If it is cracked you have these options:
1) clean the exhaust crossover (muriatic acid) and fill it with Mondello metal (part number ZA-12 = 10 lb @ $149.00 + shipping)
http://www.mondellotwister.com/index.htm
2) clean the exhaust crossover (muriatic acid) and take it to a foundry and have it filled with aluminum
Note: this has been done successfully innumerable times by GMCers.
3) clean the exhaust crossover (muriatic acid) and fill it with ceramic material: http://www.cotronics.com/vo/cotr/
Note: this has been done by a GMCer but no report as to whether or not it was a success
4) clean the exhaust crossover (muriatic acid) and fill it with Hardblok: http://www.hardblok.com/
Note: this has never been used on a GMC intake AFAIK
5) replace the manifold with a serviceable cast iron manifold: http://www.appliedgmc.com/prod.itml/icOid/569
Note: you must use one off a Toronado or you will have to raise the engine cover by building a "dog house" over it.
6) replace the manifold with an aluminum one: http://www.appliedgmc.com/prod.itml/icOid/568
Note: if you decide to go this route it is IMPERATIVE that the mechanic calls and speaks to Jim K about the installation procedure.
7) replace it with an Edelbrock "Performer" manifold: http://www.summitracing.com/parts/EDL-2151/
Note: if you decide to go this route you will have to raise the engine cover by building a "dog house" over it.
Thh thh thh thh atts all folks! ;-)
Regards,
Rob M.
-----Original Message-----
From: Lyle A. Rigdon
Hi All,
Wow... I certainly didn't mean to set off such an intense debate. Let me say up front that I do have confidence in the shop that has
the carb. They have done previous work for us on other vehicles (Corvair) and have always been top notch and very upfront with what
was needed and what they were doing. Members of the local Corvair club use them for anything GM.. not just our little 'Vairs. I have
never, ever heard anyone speak unkindly about their work. Could they be mistaken? Sure, we all can be from time to time. Would they
be up to some skulduggery..? Never.
When I spoke with them about rebuilding the carb for the GMC, they seemed to understand - without any prompting - that it was going
to require a different rebuild than the Q-jet from your typical Toronado. However, even though they have extensive GM
experience, they are not GMC folks and that is exactly why I turned to this group for advice.
The way they explained the heat tube to me is that it runs through the intake and the only way to replace it is to remove the intake
to get at it. I have not pulled the choke housing to see if it just has the short "loop" pipe that can be gotten at by removing the
two bolts mounting it to the intake. I will try to do that this evening or tomorrow and will report back to the group.
Please do know how much I appreciate everyone's input here. I am NOT an engine guy, but can wobble along fairly well with reasonably
clear instructions.
Regards,
Lyle
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
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| Re: [GMCnet] Fw: Intake Manifold Question [message #159047 is a reply to message #158889] |
Thu, 02 February 2012 21:28 |
ejuk8em
Messages: 90
Registered: July 2010
Karma: 0
|
Member |
|
|
Hi Rob,
Thanks for the wonderful info!!! I soaked the bolts in penetrating fluid for the three days and then promptly broke off the first bolt with only two short turns with a 3/8th ratchet. So, it looks like the intake is going to need to come out to get at it. I'll order the parts from Jim and will call Patterson about the recurve. That carb is already finished. I've located a local machine shop that can tank and check the intake for cracks and and take care of the broken bolt at the same time. I think most of our under hood hoses and vacuum lines are original and long over due for replacement..... So now is the time. Let's hope it stays warm a bit longer in Illinois. Working in the driveway leaves a lot to be desired.
Again, many thanks!
Lyle
Sent from my iPad
On Feb 1, 2012, at 4:29 PM, "Rob Mueller" <robmueller@iinet.net.au> wrote:
> Lyle,
>
> Some real smart guy once said "a picture is worth a thousand words" so here you go:
>
> http://www.appliedgmc.com/prod.itml/icOid/805
>
> I assume that your mechanic will realize that the bolts that retain the existing choke stove will be rusted in solid and a real
> bitch to get out without shearing them and spray them with a penetrating fluid for a couple of days before he tries to remove them.
>
> As far as the carb goes, personally I would NOT trust anyone except Dick Paterson to rebuild it.
>
> http://www.paterson-gmc.com/gmc-motorhome/carburation/
>
> Also you might want to consider having Dick re-build / re-curve your distributor:
>
> http://www.paterson-gmc.com/street-strip-hot-rod/ignition/
>
> I installed these two items from Dick on my GMC and COULD NOT BELIEVE how much better it ran, it was like day and night or as we say
> Downunder "chalk and cheese!" Give Dick a call I GA-RON-TEE it will be worth the price of a phone call!
>
> If when the mechanic removes the carb and checks the intake manifold for cracks if it is NOT cracked the crossover can be blocked
> with this kit:
>
> http://www.appliedgmc.com/prod.itml/icOid/799
>
> If it is cracked you have these options:
>
> 1) clean the exhaust crossover (muriatic acid) and fill it with Mondello metal (part number ZA-12 = 10 lb @ $149.00 + shipping)
> http://www.mondellotwister.com/index.htm
>
> 2) clean the exhaust crossover (muriatic acid) and take it to a foundry and have it filled with aluminum
> Note: this has been done successfully innumerable times by GMCers.
>
> 3) clean the exhaust crossover (muriatic acid) and fill it with ceramic material: http://www.cotronics.com/vo/cotr/
> Note: this has been done by a GMCer but no report as to whether or not it was a success
>
> 4) clean the exhaust crossover (muriatic acid) and fill it with Hardblok: http://www.hardblok.com/
> Note: this has never been used on a GMC intake AFAIK
>
> 5) replace the manifold with a serviceable cast iron manifold: http://www.appliedgmc.com/prod.itml/icOid/569
> Note: you must use one off a Toronado or you will have to raise the engine cover by building a "dog house" over it.
>
> 6) replace the manifold with an aluminum one: http://www.appliedgmc.com/prod.itml/icOid/568
> Note: if you decide to go this route it is IMPERATIVE that the mechanic calls and speaks to Jim K about the installation procedure.
>
> 7) replace it with an Edelbrock "Performer" manifold: http://www.summitracing.com/parts/EDL-2151/
> Note: if you decide to go this route you will have to raise the engine cover by building a "dog house" over it.
>
> Thh thh thh thh atts all folks! ;-)
>
> Regards,
> Rob M.
>
>
> -----Original Message-----
> From: Lyle A. Rigdon
>
>
> Hi All,
> Wow... I certainly didn't mean to set off such an intense debate. Let me say up front that I do have confidence in the shop that has
> the carb. They have done previous work for us on other vehicles (Corvair) and have always been top notch and very upfront with what
> was needed and what they were doing. Members of the local Corvair club use them for anything GM.. not just our little 'Vairs. I have
> never, ever heard anyone speak unkindly about their work. Could they be mistaken? Sure, we all can be from time to time. Would they
> be up to some skulduggery..? Never.
>
> When I spoke with them about rebuilding the carb for the GMC, they seemed to understand - without any prompting - that it was going
> to require a different rebuild than the Q-jet from your typical Toronado. However, even though they have extensive GM
> experience, they are not GMC folks and that is exactly why I turned to this group for advice.
>
> The way they explained the heat tube to me is that it runs through the intake and the only way to replace it is to remove the intake
> to get at it. I have not pulled the choke housing to see if it just has the short "loop" pipe that can be gotten at by removing the
> two bolts mounting it to the intake. I will try to do that this evening or tomorrow and will report back to the group.
>
> Please do know how much I appreciate everyone's input here. I am NOT an engine guy, but can wobble along fairly well with reasonably
> clear instructions.
> Regards,
> Lyle
>
>
>
> _______________________________________________
> 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] Fw: Intake Manifold Question [message #159049 is a reply to message #159047] |
Thu, 02 February 2012 21:44 |
Dennis S
Messages: 3046
Registered: November 2005
Karma: 2
|
Senior Member |
|
|
Lyle,
Don't give up --- you can drill out the old bolt and retap the hole -- I have had to do it on two intakes. Not a bad job -- run the shop vac while you drill and it will keep the chips picked up.
Dennis
Dennis S
73 Painted Desert 230
Memphis TN Metro
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| Re: [GMCnet] Fw: Intake Manifold Question [message #159050 is a reply to message #159047] |
Thu, 02 February 2012 21:46 |
|
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
|
Senior Member |
|
|
Lyle,
Clear demonstration that Murphy is alive and well! At the end of the day it'll be better if you plug the crossover, cap the choke
well and use an electric choke.
When you attempt to remove the intake manifold it will probably be stuck to the turkey tray and the turkey tray stuck to the heads.
Take a 1" wide putty knife and insert it between the manifold and heads in each of the four corners where I will do the least damage
when you tap it in a tiny bit to break the manifold loose. Bolt a section of chain to the carb bolt holes and when you're ready to
lift it off pull it straight up. It would be a good idea to have someone to give you a hand steadying the manifold as you lift it as
it is pretty heavy. The reason for pulling it straight up is because the bottom of the manifold is going to be full of baked on crud
and the turkey tray will be also. The straighter you pull it up the less of that crud will fall into the lifter valley. You can use
a shop vac to clean up the lifter valley.
Let us know when you get it ready to go back in and we'll give you some more tips.
Regards,
Rob M.
-----Original Message-----
From: Lyle Rigdon
Hi Rob,
Thanks for the wonderful info!!! I soaked the bolts in penetrating fluid for the three days and then promptly broke off the first
bolt with only two short turns with a 3/8th ratchet. So, it looks like the intake is going to need to come out to get at it. I'll
order the parts from Jim and will call Patterson about the recurve. That carb is already finished. I've located a local machine shop
that can tank and check the intake for cracks and and take care of the broken bolt at the same time. I think most of our under hood
hoses and vacuum lines are original and long over due for replacement..... So now is the time. Let's hope it stays warm a bit
longer in Illinois. Working in the driveway leaves a lot to be desired.
Again, many thanks!
Lyle
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
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| Re: [GMCnet] Fw: Intake Manifold Question [message #159051 is a reply to message #158742] |
Thu, 02 February 2012 21:49 |
KB
Messages: 1262
Registered: September 2009
Karma: 0
|
Senior Member |
|
|
I was just researching this since blocking the crossover is on my short list.
Can't for the life of me find it right now, but I saw lots of references
to using furnace cement as a filler if the manifold is cracked. Should
be in addition to block off plates I suspect. I think I saw a posting from Roy Keen
(maybe?) about having run with furnace cement for 20 years and no problems, but
it could be those darn hallucinations acting up again. I swear I'd even found
a picture album on the photo site, but of course I can't find it now. Looked
a whole lot easier than the hot metal pour approach.
Now I just have to figure out what furnace cement is...
Karen
1973 23'
1975 26'
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Karen
1975 26'
San Jose, CA
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| Re: [GMCnet] Fw: Intake Manifold Question [message #159052 is a reply to message #159047] |
Thu, 02 February 2012 21:55 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
| ejuk8em wrote on Thu, 02 February 2012 21:28 |
Hi Rob,
Thanks for the wonderful info!!! I soaked the bolts in penetrating fluid for the three days and then promptly broke off the first bolt with only two short turns with a 3/8th ratchet. So, it looks like the intake is going to need to come out to get at it. I'll order the parts from Jim and will call Patterson about the recurve. That carb is already finished. I've located a local machine shop that can tank and check the intake for cracks and and take care of the broken bolt at the same time. I think most of our under hood hoses and vacuum lines are original and long over due for replacement..... So now is the time. Let's hope it stays warm a bit longer in Illinois. Working in the driveway leaves a lot to be desired.
Again, many thanks!
Lyle
Sent from my iPad
|
If it is not broken off flush get a pair of vice grips and some Kroil. Heat the spot with a propane torch and shock cool it again with the spray Kroil. Do this two or three times then try turning the vice grips.
If the broken bolt is flush just drill it out and try and easy-out plus Kroil and heat.
If all of that fails, drill it out to the size needed for a tap and cut some new threads for the same size bolt. I believe it is 1/4-20. There is no need to remove the manifold to do any of this.
If you are absolutely determined to remove the manifold, get the blocking plates and intake gasket for Jim K. Install install the plates when reinstalling the manifold.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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