Blown exhaust gasket.....

6

6cuda6

Active member
Jul 1, 2019
945
163
43
59
Ontario, Canada
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
 
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
 
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
 
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 <

> 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
>
 
They work great with stock manifolds but will not fit headers.

Emery Stora

>
> 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
>
 
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

>
> 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 <

>
>> 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
 
https://www.gmcrvparts.com/product-p/gm12-030.2.htm

On Wed, Aug 7, 2019 at 2:38 PM Emery Stora via Gmclist <

> 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 <

> >
> > 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 <

> >
> >> 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
http://www.appliedgmc.com
1-800-752-7502
 
https://www.gmcrvparts.com/product-p/gm12-030.15.htm

> https://www.gmcrvparts.com/product-p/gm12-030.2.htm
>
> On Wed, Aug 7, 2019 at 2:38 PM Emery Stora via Gmclist <

>
>> 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 <

>> >
>> > 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 <

>> >
>> >> 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
> http://www.appliedgmc.com
> 1-800-752-7502
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
You must log in or register to reply here.
Get your shine on at www.cruzingear.co
GMCMI Spring 2026 Rally

Share this page

Share this page
Top Bottom
Back