< BOUNCE> Exhaust Manifolds

patrick flowers

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Sep 19, 1997
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[ADMIN Note - The multipart filter found its first victim. The
following was
sent in HTML. Please post in plain text only.]

> Date: Thu, 22 Oct 1998 11:25:59 -0400
> From: "Loren (Skip) Newhouse"
> To: gmcmotorhome
> Subject: Re: GMC: Exhaust Manifolds
>

>
> > OK. Should I heat them also. I Have a Mapp/Oxy set I got from Home Depot.
> > Gas only last about 10 min when cutting. A little longer when just
> > heating.
> > Rob Teed
> >
> > Rob,
>
> I recently had to remove my left exhaust manifold. I got lots of
> information and advise from GMCnet and from the GMC Motorhome International
> Newsletters. It was pointed out that the center bolt is the one that will
> most likely break. This is because the other four have a hole that exits at
> the spark plug indent and can be lubed with penetrating oil. (Some people
> have drilled a similar hole into the center bolt hole.) Put the oil in and
> give it time to penetrate, then heat the bolts and add some more oil. This
> should work. I was lucky, all bolts came out without breakage. Using the
> advise from the newsletter, I had the manifold resurfaced, cleaned the
> mating surface on the head with a wire brush and emery cloth and reinstalled
> the manifold using "Permatex" Ultra copper high temp gasket maker. I also
> used new grade 8 bolts with the old thick washers. So far it is working
> well. The copper gasket maker is suppose to transfer heat better that
> gaskets. good luck.
> Skip Newhouse 75 Avion Hagerstown Maryland
 
Thanks Skip,
The info came just in time. My friends got both
manifolds off. Both Cracked! Five bolts Heads
broke off. Put the penatrating oil where You said.
Hopefully all will go well.
Rob Teed

> -----Original Message-----
> From: owner-gmcmotorhome
> [mailto:owner-gmcmotorhome]On Behalf Of Patrick Flowers
> Sent: Thursday, October 22, 1998 4:30 PM
> To: gmcmotorhome
> Subject: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds
>
>
> [ADMIN Note - The multipart filter found its first victim. The
> following was
> sent in HTML. Please post in plain text only.]
>
> > Date: Thu, 22 Oct 1998 11:25:59 -0400
> > From: "Loren (Skip) Newhouse"
> > To: gmcmotorhome
> > Subject: Re: GMC: Exhaust Manifolds
> >

> >
> > > OK. Should I heat them also. I Have a Mapp/Oxy set I got from
> Home Depot.
> > > Gas only last about 10 min when cutting. A little longer when just
> > > heating.
> > > Rob Teed
> > >
> > > Rob,
> >
> > I recently had to remove my left exhaust manifold. I got lots of
> > information and advise from GMCnet and from the GMC Motorhome
> International
> > Newsletters. It was pointed out that the center bolt is the one
> that will
> > most likely break. This is because the other four have a hole
> that exits at
> > the spark plug indent and can be lubed with penetrating oil.
> (Some people
> > have drilled a similar hole into the center bolt hole.) Put the
> oil in and
> > give it time to penetrate, then heat the bolts and add some
> more oil. This
> > should work. I was lucky, all bolts came out without breakage. Using the
> > advise from the newsletter, I had the manifold resurfaced, cleaned the
> > mating surface on the head with a wire brush and emery cloth
> and reinstalled
> > the manifold using "Permatex" Ultra copper high temp gasket
> maker. I also
> > used new grade 8 bolts with the old thick washers. So far it is working
> > well. The copper gasket maker is suppose to transfer heat better that
> > gaskets. good luck.
> > Skip Newhouse 75 Avion Hagerstown Maryland
>
 
What are you going to replace them with? Have you considered the Thornly
headers and the copper gasket from Joe Mondello? Good ideas. If you do think
about getting them Ceramic Coated in and out. HPC does it in Utah. Chuck

> Thanks Skip,
> The info came just in time. My friends got both
> manifolds off. Both Cracked! Five bolts Heads
> broke off. Put the penatrating oil where You said.
> Hopefully all will go well.
> Rob Teed
>
> > -----Original Message-----
> > From: owner-gmcmotorhome
> > [mailto:owner-gmcmotorhome]On Behalf Of Patrick Flowers
> > Sent: Thursday, October 22, 1998 4:30 PM
> > To: gmcmotorhome
> > Subject: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds
> >
> >
> > [ADMIN Note - The multipart filter found its first victim. The
> > following was
> > sent in HTML. Please post in plain text only.]
> >
> > > Date: Thu, 22 Oct 1998 11:25:59 -0400
> > > From: "Loren (Skip) Newhouse"
> > > To: gmcmotorhome
> > > Subject: Re: GMC: Exhaust Manifolds
> > >

> > >
> > > > OK. Should I heat them also. I Have a Mapp/Oxy set I got from
> > Home Depot.
> > > > Gas only last about 10 min when cutting. A little longer when just
> > > > heating.
> > > > Rob Teed
> > > >
> > > > Rob,
> > >
> > > I recently had to remove my left exhaust manifold. I got lots of
> > > information and advise from GMCnet and from the GMC Motorhome
> > International
> > > Newsletters. It was pointed out that the center bolt is the one
> > that will
> > > most likely break. This is because the other four have a hole
> > that exits at
> > > the spark plug indent and can be lubed with penetrating oil.
> > (Some people
> > > have drilled a similar hole into the center bolt hole.) Put the
> > oil in and
> > > give it time to penetrate, then heat the bolts and add some
> > more oil. This
> > > should work. I was lucky, all bolts came out without breakage. Using the
> > > advise from the newsletter, I had the manifold resurfaced, cleaned the
> > > mating surface on the head with a wire brush and emery cloth
> > and reinstalled
> > > the manifold using "Permatex" Ultra copper high temp gasket
> > maker. I also
> > > used new grade 8 bolts with the old thick washers. So far it is working
> > > well. The copper gasket maker is suppose to transfer heat better that
> > > gaskets. good luck.
> > > Skip Newhouse 75 Avion Hagerstown Maryland
> >
 
Chuck,
I'm think I want to put stock manifolds on. The
rest of the Exhaust system looks brand new, and I
dont want to mess with it. Are You asking if I want
to ceramic the stock manifolds?
Rob Teed

> -----Original Message-----
> From: owner-gmcmotorhome
> [mailto:owner-gmcmotorhome]On Behalf Of Chuck Will
> Sent: Thursday, October 22, 1998 8:37 PM
> To: gmcmotorhome
> Subject: Re: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds
>
>
> What are you going to replace them with? Have you considered the Thornly
> headers and the copper gasket from Joe Mondello? Good ideas. If
> you do think
> about getting them Ceramic Coated in and out. HPC does it in Utah. Chuck
>

>
> > Thanks Skip,
> > The info came just in time. My friends got both
> > manifolds off. Both Cracked! Five bolts Heads
> > broke off. Put the penatrating oil where You said.
> > Hopefully all will go well.
> > Rob Teed
> >
> > > -----Original Message-----
> > > From: owner-gmcmotorhome
> > > [mailto:owner-gmcmotorhome]On Behalf Of
> Patrick Flowers
> > > Sent: Thursday, October 22, 1998 4:30 PM
> > > To: gmcmotorhome
> > > Subject: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds
> > >
> > >
> > > [ADMIN Note - The multipart filter found its first victim. The
> > > following was
> > > sent in HTML. Please post in plain text only.]
> > >
> > > > Date: Thu, 22 Oct 1998 11:25:59 -0400
> > > > From: "Loren (Skip) Newhouse"
> > > > To: gmcmotorhome
> > > > Subject: Re: GMC: Exhaust Manifolds
> > > >

> > > >
> > > > > OK. Should I heat them also. I Have a Mapp/Oxy set I got from
> > > Home Depot.
> > > > > Gas only last about 10 min when cutting. A little longer
> when just
> > > > > heating.
> > > > > Rob Teed
> > > > >
> > > > > Rob,
> > > >
> > > > I recently had to remove my left exhaust manifold. I got lots of
> > > > information and advise from GMCnet and from the GMC Motorhome
> > > International
> > > > Newsletters. It was pointed out that the center bolt is the one
> > > that will
> > > > most likely break. This is because the other four have a hole
> > > that exits at
> > > > the spark plug indent and can be lubed with penetrating oil.
> > > (Some people
> > > > have drilled a similar hole into the center bolt hole.) Put the
> > > oil in and
> > > > give it time to penetrate, then heat the bolts and add some
> > > more oil. This
> > > > should work. I was lucky, all bolts came out without
> breakage. Using the
> > > > advise from the newsletter, I had the manifold resurfaced,
> cleaned the
> > > > mating surface on the head with a wire brush and emery cloth
> > > and reinstalled
> > > > the manifold using "Permatex" Ultra copper high temp gasket
> > > maker. I also
> > > > used new grade 8 bolts with the old thick washers. So far
> it is working
> > > > well. The copper gasket maker is suppose to transfer heat
> better that
> > > > gaskets. good luck.
> > > > Skip Newhouse 75 Avion Hagerstown Maryland
> > >
>
>
>
>
 
> Thanks Skip,
> The info came just in time. My friends got both
> manifolds off. Both Cracked! Five bolts Heads
> broke off. Put the penatrating oil where You said.
> Hopefully all will go well.
> Rob Teed
>
> Rob,

Me again. I got a message from the GMCnet administrator telling me that my
message was trapped in the multifilter because I used the wrong language(HTML).
I retrieved the message and added the info about using milk of magnesia as an
anti-seize and sent it again.Skip 75 Avion Hagetstown MD
 
Hi Skip,
Yep,
I saw that the message had bounced, But I still
got it. I'll tell Ya, I really like this GMC, And
this newsgroup. I save all the Messages to My harddrive
then use " Find " in outlook to get old info that I
need. Thanks to Everyone for all their help.
Rob Teed 74' Painted Desert Lansing,Mi

> -----Original Message-----
> From: owner-gmcmotorhome
> [mailto:owner-gmcmotorhome]On Behalf Of Loren (Skip)
> Newhouse
> Sent: Friday, October 23, 1998 12:10 AM
> To: gmcmotorhome
> Subject: Re: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds
>
>
>
>

>
> > Thanks Skip,
> > The info came just in time. My friends got both
> > manifolds off. Both Cracked! Five bolts Heads
> > broke off. Put the penatrating oil where You said.
> > Hopefully all will go well.
> > Rob Teed
> >
> > Rob,
>
> Me again. I got a message from the GMCnet administrator telling me that my
> message was trapped in the multifilter because I used the wrong
> language(HTML).
> I retrieved the message and added the info about using milk of
> magnesia as an
> anti-seize and sent it again.Skip 75 Avion Hagetstown MD
>
>
>
 
I think they do that too. But at the very least I would consider at
least having them powder coated. It will help some. As far as messing
around with the exhaust system. It is not necessary. The tail pipe is
ok and the muffler recommendation of Flow Master will help your engine
breathe better. If you check with some of the GMC'ers you will find out
that you can raise your acceleration and horsepower a little by doing
those things. I have been messing around with my GMC since 1989. I
honestly would not have another motor home. But on the other hand
initial cost and maintenance and repairs (upgrades etc.) I have spent
about 5K a year just to drive it. That does not count the gas oil
and insurance, tires and general lubrication. I am retired now and the
cost may well put me out of the business if it keep on. I blew three
engines last year. The first was my original 455 "L" Block it was one
of the last from General Motors right out of the crate. That is why I
wanted to keep it and have it rebuilt. Any way Barber Olds in Salt Lake
City ordered an engine from The Motor Works out of Spokane Washington.
That motor lasted 300 miles because in the guarantee it specifies that
the oil cooler and lines will be replaced. I doubt seriously if they
put in the required cam and crank and oil restrictors, valve
rotators, line boered it and machined the rods to allow the oil to get
to the bearings. When the engine let go it was because of spun bearing
and three cracked rings in the 4 and 5 cylinder. I had been driving it
fairly hard 65-70 MPH and the oil probably was thrown into the rockers,
in doing this there is no oil in the lower pan to do what it is supposed
to do. Another lesson I learned nearly 9 years later while researching
my problems. The guarantee required the engine to be shipped back to
the Motor Works for their examination and repair. I doubt seriously if
they even did any thing other than turn it upside down and slap in the
new bearings. Incidentally when the engine was pulled apart the
bearing were out as much as .005 out. Any way that engine lasted 700
miles. In all I had between 8 and 9 K into them. When I finally got
home I had my original engine here and had it rebuilt by Tom Green of
Rural Machine. Joe Mondello provided allot of guidance and all the
innards. It is really a good strong engine. The Thornly headers on the
right side go out far enough so you do not have to worry about the oil
cooler lines being to close to the manifolds or headers. This is another
GMC problem in itself. The oil lines should be changed out because of
the heat they are exposed too. They may look fine but the material
inside does break down from heat. I replace my radiator about
three years ago and in doing so thought I was getting the whole
radiator. Not so. The cooler that is located below has not be made
for nearly 10 years and if you can find one buy them up. They are just
not around. I opted to have the cooler installed outside and it is
located near the transmission cooler. I have the old GMC oil cooler
for evidence in my upcoming law suit. One of the mechanics charged me
for a new oil cooler etc. It cost me nearly 800.00 if my memory serve
me right and several hundred to do the work. Any way to sum it
up. There just are nolonger any of these critters around. So if you
damage the bearings and the contamination circulates into the cooler.
You just have to dump it and start afresh. The Second time my GMC sat
in Beaver Utah for nearly 6 months awaiting the The Motor Works repair
and the mechanics time to put it in. In the process the intake manifold
was cracked and I had to find another one of them. Again the Tornado
is a hard beast to come by. If you find one you might just buy it and
park it somewhere for a doner. If you stay into this GMC thing for
any time you will be glad to have the parts.

I don't want to sound morbid but there are lots of things that can go
wrong with these coaches. You need to stay on top of you bearings.
They should be packed about 30K Recommend they be replaced. The hubs
and knuckles are press fit with the bearings so they sometimes wear too.
Especially if the coach has not been taken care of. Regular Maintenance.
Many years ago I took up Motorcycle riding. One of the guys I rode with
said, "Chuck, if your going to ride this thing you better learn how to
sevrvice it" I never forgot that. I have a Harley Davidson that I
completely re chromed, painted and restored. Any and all parts that
came off were replaced. Nuts and bolts etc. My GMC is just about
that way too. Every time you take something off to service it you find
it needs to be replace, repaired etc. My coach is I am happy to say like
new mechanical condition, Final Drive, Transmission with the Caspro
Gears and his final drive. I think his Shocks are the besst too. I
will never wear out the ones I have on them, KYB's but when funds are
available I will replace them. The steering box is probably worn too.
I greased mine every time I change the oil and I grease the pins every
time I stop at night. It sounds crazy but you will find out that general
maintenance is a must. I put those zirk covers on the fittings so I can
find them. There are thirteen of them in the front end. I usually miss
something. It is the one in the steering knuckles. There are two.

Back to your manifolds. If $$ is the problem I would just paint them or
have them coated. The HPC is on the WEB and the 800 number is 456-4721,
Dave or Cory are very knowledgeable and will help you allot.
By 4 now Chuck,
Eleganza ii
1978, Lompoc, CA.

> Chuck,
> I'm think I want to put stock manifolds on. The
> rest of the Exhaust system looks brand new, and I
> dont want to mess with it. Are You asking if I want
> to ceramic the stock manifolds?
> Rob Teed
 
Chuck,
I think We will all have a few war storys to
tell. I hope to see You on the road sometime.
We hope to have ours on the road by March. But
will have to retain the Orange paint till next
spring:(
See Ya,
Rob Teed 74 Painted Desert Mich.
 
When you find someone who will paint and do a good job let know I want
to change too. I'd like to get a more up to date graphics rather than
the BLAH DRAB ORIGINAL BROWN, BEIGE AND GOLD STRIPES. It is original
looking but I am not into that any more. My 56 F-100s are awaiting
paint now. I want to do the Big Window in the new Ford Plum color. The
little window is my wifes and she wants it the Mauve with that and Gray
upholstery. Tom is building an engine for hers now and a transmission.
That was the deal I had to settle for. My Harley for the two engines
(GMC and F-100). I hate to let it go but such is the way things are
when you run out of $$$ to repair things. By Chuck

> Chuck,
> I think We will all have a few war storys to
> tell. I hope to see You on the road sometime.
> We hope to have ours on the road by March. But
> will have to retain the Orange paint till next
> spring:(
> See Ya,
> Rob Teed 74 Painted Desert Mich.
 
I hope the FAA is not reading these messages. I don't think that milk of
magnesia is an approved anti-seize compound for use on aircraft. Anti-seize
is available from any auto parts store and it is not very expensive. I used
copper gaskets and red RTV and silver anti-seize when installing my Thorley
headers. I have not had any leaks since and I have put 9,000 miles on the
GMC. I would highly recommend anyone with manifold leaks to bite the bullet
and go the header route.

Russ Bethel
rbethel

- -----Original Message-----
From: Loren (Skip) Newhouse
To: gmcmotorhome
Date: Thursday, October 22, 1998 11:10 PM
Subject: Re: GMC: fwd:< BOUNCE> Re: Exhaust Manifolds

>
>

>
>> Thanks Skip,
>> The info came just in time. My friends got both
>> manifolds off. Both Cracked! Five bolts Heads
>> broke off. Put the penatrating oil where You said.
>> Hopefully all will go well.
>> Rob Teed
>>
>> Rob,
>
>Me again. I got a message from the GMCnet administrator telling me that my
>message was trapped in the multifilter because I used the wrong
language(HTML).
>I retrieved the message and added the info about using milk of magnesia as
an
>anti-seize and sent it again.Skip 75 Avion Hagetstown MD
>
>