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Blown exhaust gasket..... [message #345965] Fri, 02 August 2019 19:57 Go to next message
6cuda6 is currently offline  6cuda6   Canada
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Registered: June 2019
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Still working my way through the little list of "godda do for safety inspection" and next one is a blown right side exhaust manifold gasket on the 403.

Any suggestions on brands etc....i didnt want to do this once let alone ever again so the best gasket available if you please.


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: Blown exhaust gasket..... [message #345966 is a reply to message #345965] Fri, 02 August 2019 20:43 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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And yes i know they arent supposed to have any but this motor does....so for the time being its going to get a new one (not replacing both ...one is going to be bad enough)

Rich Mondor, Brockville, ON 77 Hughes 2600
Re: Blown exhaust gasket..... [message #345970 is a reply to message #345966] Fri, 02 August 2019 23:04 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

I personally have had VERY good luck using Dave Lenzi's embossed copper exhaust manifold gaskets. Installed per his detailed instructions, I have never had to replace one unless the manifold had to come off for some other reason. You can get them directly from Dave or from Applied GMC.

Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Blown exhaust gasket..... [message #345972 is a reply to message #345970] Fri, 02 August 2019 23:14 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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My 403 has Doug Thorley headers, they are coated inside and out, don't know
with what, but they are still in good shape since 2008. The flanges are
very thick, don't know if current ones are like mine. They have remflex
graphite gaskets, still in place, and not leaking. Can't complain one bit.
Jim Hupy
Salem, Or

On Fri, Aug 2, 2019, 9:05 PM Carl Stouffer via Gmclist <
gmclist@list.gmcnet.org> wrote:

> I personally have had VERY good luck using Dave Lenzi's embossed copper
> exhaust manifold gaskets. Installed per his detailed instructions, I have
> never had to replace one unless the manifold had to come off for some
> other reason. You can get them directly from Dave or from Applied GMC.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Blown exhaust gasket..... [message #346175 is a reply to message #345972] Wed, 07 August 2019 16:37 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
Messages: 959
Registered: January 2011
Karma: 4
Senior Member
The Thorley headers are made with a ceramic coating.
Thorley no longer lists the headers in their catalog. 355y for 455 engine.

They say they make about 10 sets per year in November for one customer.

I had a leaking seam and they made a free replacement for me under their lifetime warranty.
They interrupted their manufacturing schedule to make me one side right away.
Great company.

Emery Stora

> On Aug 2, 2019, at 10:14 PM, James Hupy via Gmclist wrote:
>
> My 403 has Doug Thorley headers, they are coated inside and out, don't know
> with what, but they are still in good shape since 2008. The flanges are
> very thick, don't know if current ones are like mine. They have remflex
> graphite gaskets, still in place, and not leaking. Can't complain one bit.
> Jim Hupy
> Salem, Or
>
> On Fri, Aug 2, 2019, 9:05 PM Carl Stouffer via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> I personally have had VERY good luck using Dave Lenzi's embossed copper
>> exhaust manifold gaskets. Installed per his detailed instructions, I have
>> never had to replace one unless the manifold had to come off for some
>> other reason. You can get them directly from Dave or from Applied GMC.
>> --
>> Carl Stouffer
>> '75 ex Palm Beach
>> Tucson, AZ.
>> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
>> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
>> Eagles,
>> Solar battery charging. GMCSJ and GMCMI member
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Blown exhaust gasket..... [message #346176 is a reply to message #345970] Wed, 07 August 2019 16:33 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
They work great with stock manifolds but will not fit headers.

Emery Stora

> On Aug 2, 2019, at 10:04 PM, Carl Stouffer via Gmclist wrote:
>
> I personally have had VERY good luck using Dave Lenzi's embossed copper exhaust manifold gaskets. Installed per his detailed instructions, I have
> never had to replace one unless the manifold had to come off for some other reason. You can get them directly from Dave or from Applied GMC.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>


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Re: [GMCnet] Blown exhaust gasket..... [message #346191 is a reply to message #346175] Wed, 07 August 2019 18:25 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
https://www.gmcrvparts.com/product-p/gm12-030.2.htm

On Wed, Aug 7, 2019 at 2:38 PM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> The Thorley headers are made with a ceramic coating.
> Thorley no longer lists the headers in their catalog. 355y for 455 engine.
>
> They say they make about 10 sets per year in November for one customer.
>
> I had a leaking seam and they made a free replacement for me under their
> lifetime warranty.
> They interrupted their manufacturing schedule to make me one side right
> away.
> Great company.
>
> Emery Stora
>
>> On Aug 2, 2019, at 10:14 PM, James Hupy via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> My 403 has Doug Thorley headers, they are coated inside and out, don't
> know
>> with what, but they are still in good shape since 2008. The flanges are
>> very thick, don't know if current ones are like mine. They have remflex
>> graphite gaskets, still in place, and not leaking. Can't complain one
> bit.
>> Jim Hupy
>> Salem, Or
>>
>> On Fri, Aug 2, 2019, 9:05 PM Carl Stouffer via Gmclist > gmclist@list.gmcnet.org> wrote:
>>
>>> I personally have had VERY good luck using Dave Lenzi's embossed copper
>>> exhaust manifold gaskets. Installed per his detailed instructions, I
> have
>>> never had to replace one unless the manifold had to come off for some
>>> other reason. You can get them directly from Dave or from Applied GMC.
>>> --
>>> Carl Stouffer
>>> '75 ex Palm Beach
>>> Tucson, AZ.
>>> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
>>> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
>>> Eagles,
>>> Solar battery charging. GMCSJ and GMCMI member
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Blown exhaust gasket..... [message #346192 is a reply to message #345972] Wed, 07 August 2019 18:27 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
https://www.gmcrvparts.com/product-p/gm12-030.15.htm

On Wed, Aug 7, 2019 at 4:25 PM Jim Kanomata wrote:

> https://www.gmcrvparts.com/product-p/gm12-030.2.htm
>
> On Wed, Aug 7, 2019 at 2:38 PM Emery Stora via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> The Thorley headers are made with a ceramic coating.
>> Thorley no longer lists the headers in their catalog. 355y for 455 engine.
>>
>> They say they make about 10 sets per year in November for one customer.
>>
>> I had a leaking seam and they made a free replacement for me under their
>> lifetime warranty.
>> They interrupted their manufacturing schedule to make me one side right
>> away.
>> Great company.
>>
>> Emery Stora
>>
>>> On Aug 2, 2019, at 10:14 PM, James Hupy via Gmclist > gmclist@list.gmcnet.org> wrote:
>>>
>>> My 403 has Doug Thorley headers, they are coated inside and out, don't
>> know
>>> with what, but they are still in good shape since 2008. The flanges are
>>> very thick, don't know if current ones are like mine. They have remflex
>>> graphite gaskets, still in place, and not leaking. Can't complain one
>> bit.
>>> Jim Hupy
>>> Salem, Or
>>>
>>> On Fri, Aug 2, 2019, 9:05 PM Carl Stouffer via Gmclist >> gmclist@list.gmcnet.org> wrote:
>>>
>>>> I personally have had VERY good luck using Dave Lenzi's embossed copper
>>>> exhaust manifold gaskets. Installed per his detailed instructions, I
>> have
>>>> never had to replace one unless the manifold had to come off for some
>>>> other reason. You can get them directly from Dave or from Applied GMC.
>>>> --
>>>> Carl Stouffer
>>>> '75 ex Palm Beach
>>>> Tucson, AZ.
>>>> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final
>> drive,
>>>> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
>>>> Eagles,
>>>> Solar battery charging. GMCSJ and GMCMI member
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Blown exhaust gasket..... [message #346217 is a reply to message #346192] Thu, 08 August 2019 07:54 Go to previous message
Justin Brady is currently offline  Justin Brady   United States
Messages: 769
Registered: April 2015
Location: Bell Buckle, TN
Karma: 11
Senior Member
I'll second/third remflex. They will fill in any little voids or nicks in the surface and keep a nice seal.

Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
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