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[GMCnet] Corrosion [message #276222] Sun, 19 April 2015 13:47 Go to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Hi,

as can be seen from http://possy.de/corrosion.JPG the black thingie
around on the drivers and passengers side with the position lights in
it, seems corroded.

Anyone has a BTDT (preferable with pics) on what to do to get rid of this?

Please ignore my parking skills ;)
--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA
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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Corrosion [message #276224 is a reply to message #276222] Sun, 19 April 2015 14:08 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Peer Oliver Schmidt wrote on Sun, 19 April 2015 11:47
Hi,

as can be seen from http://possy.de/corrosion.JPG the black thingie
around on the drivers and passengers side with the position lights in
it, seems corroded.

Anyone has a BTDT (preferable with pics) on what to do to get rid of this?

Please ignore my parking skills Wink
--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA
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. That is common in 73 to early 76 coaches the stainless rub rail wears thru the paint and the aluminum side corrodes . You would need to remove the rub rails sand and etch the damaged aluminum use body filler and finish sand then repaint when putting the rails back on and use some kind of tape to insulate the rail and keep it from rubbing thru the paint again would be helpful.



Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Corrosion [message #276234 is a reply to message #276222] Sun, 19 April 2015 17:10 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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Peer,

Sorry, your description makes no sense to me at all. Take another picture and have your wife point to the "black thingie."

Regards,
Rob M.

-----Original Message-----
From: Peer Oliver Schmidt GMC

Hi,

as can be seen from http://possy.de/corrosion.JPG the black thingie
around on the drivers and passengers side with the position lights in
it, seems corroded.

Anyone has a BTDT (preferable with pics) on what to do to get rid of this?

Please ignore my parking skills ;)
--
Best regards

Peer

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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] Corrosion [message #276243 is a reply to message #276234] Sun, 19 April 2015 19:11 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Location: Americus, GA
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Rob,

He's referring to the corrosion along the top of the beltline -- the "black
thingie" is the rubber rub strip.

Peer,

Removing the trim, stripping the paint, sanding out the corrosion, probably
applying some chemical treatment Sullie or someone else in the body
business can describe, and repainting is the only "solution". You'll find
it's very common -- I've even got a little beginning again under my 13 year
"new" paint job.

Ken H.


On Sun, Apr 19, 2015 at 6:10 PM, Robert Mueller
wrote:

> Peer,
>
> Sorry, your description makes no sense to me at all. Take another picture
> and have your wife point to the "black thingie."
>
> Regards,
> Rob M.
>
> -----Original Message-----
> From: Peer Oliver Schmidt GMC
>
> Hi,
>
> as can be seen from http://possy.de/corrosion.JPG the black thingie
> around on the drivers and passengers side with the position lights in
> it, seems corroded.
>
> Anyone has a BTDT (preferable with pics) on what to do to get rid of this?
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Corrosion [message #276247 is a reply to message #276243] Sun, 19 April 2015 20:16 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Ken,

I kinda thought that but wanted to make sure.

Peer,

To remove the rubber strip you'll probably have to flush it out as there probably is tons of dirt in behind it especially at the
bottom, IIRC I used a high pressure Karcher unit to clean it out. Once you get the rubber rub strip recess cleaned and are able to
pull the rubber rub strip out you will find that the stainless steel trim is either screwed and / or pop riveted to the main
horizontal body member. If it is screws it is a bitch to get them out as the screws are steel and the horizontal body frame member
is aluminum. Thirty plus years of dissimilar metal corrosion will keep them in there pretty well. You will wind up stripping the
cross out of the heads on a lot of them which will require they be drilled out. Been there done that.

Once you have it off you will be able to clean the corrosion off the horizontal body member and spray it with zinc chromate primer.

A common "upgrade" to that area is to replace the stainless steel trim with a piece of flat aluminum and using a rubber rub strip
from a later model. The aluminum strip needs to be small amount wider than the exposed part of the horizontal body member.

Use countersunk pop rivets and 3M - 5200 adhesive / sealer when you install the aluminum trim, it will never come off!

Run 1" masking tape down the body to mask off the side of the coach so you don't wind up with 3M-5200 all over it.

Regards,
Rob M.


-----Original Message-----
From: Ken Henderson

Rob,

He's referring to the corrosion along the top of the beltline -- the "black
thingie" is the rubber rub strip.

Peer,

Removing the trim, stripping the paint, sanding out the corrosion, probably
applying some chemical treatment Sullie or someone else in the body
business can describe, and repainting is the only "solution". You'll find
it's very common -- I've even got a little beginning again under my 13 year
"new" paint job.

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
Re: [GMCnet] Corrosion [message #276257 is a reply to message #276243] Mon, 20 April 2015 05:52 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Am 20.04.2015 um 02:11 schrieb Ken Henderson:
> Rob,
>
> He's referring to the corrosion along the top of the beltline -- the "black
> thingie" is the rubber rub strip.
>

Thanks Ken. That's exactly what I meant.

Removing strip is done by removing the caps, the lights and then pulling
out the strip, I assume?

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA

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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Corrosion [message #276271 is a reply to message #276257] Mon, 20 April 2015 08:31 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Peer Oliver Schmidt wrote on Mon, 20 April 2015 05:52


Thanks Ken. That's exactly what I meant.

Removing strip is done by removing the caps, the lights and then pulling
out the strip, I assume?

--
Best regards

Peer Oliver Schmidt



Be aware that once the caps and screws are out of that strip that it may/will start to shrink. On mine the strip on the LH side shrunk up 6 inches. On the RH side in front of the door it shrank 2 inches.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Corrosion [message #276274 is a reply to message #276271] Mon, 20 April 2015 08:50 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Registered: February 2014
Location: Germany and Scottsville, ...
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Senior Member
Steve,
> Be aware that once the caps and screws are out of that strip that it
> may/will start to shrink. On mine the strip on the LH side shrunk up 6
> inches. On the RH side in front of the door it shrank 2 inches.

thanks for the tip. What is the best way to prevent the shrinking? Work
in warm weather? Work in cold weather? Work fast?

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA

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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Corrosion [message #276279 is a reply to message #276222] Mon, 20 April 2015 09:18 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Location: Germany and Scottsville, ...
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Senior Member
Rob,
> [..]I slid the new strip [..]
where did you get the new strip from? Applied? If yes, do you have
direct link (I couldn't find it...)

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA

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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Corrosion [message #276280 is a reply to message #276271] Mon, 20 April 2015 09:17 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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Steve,

When I replaced the driver side I slid the new strip in from the rear, slid it all the way up to the front marker light then worked
my way back down the coach pushing forward as I went to compress it. I did not cut it to fit, I stuck about 8 inches excess through
a small snack Zip Lock Bag after cutting the sides of it off. I taped the bag with the strip in it to the side of the coach with
duct tape but not to tight to allow the strip to shrink. I left it like that for two years before cutting it off last fall. When I
was back there in February I noticed that it had shrunk about 1/2 inch, DAMN!

I used the old piece I had removed from the driver side on the passenger side and did the same thing but that didn't shrink.

Regards,
Rob M.

-----Original Message-----
From: Steve Southworth

Be aware that once the caps and screws are out of that strip that it may/will start to shrink. On mine the strip on the LH side
shrunk up 6 inches.

On the RH side in front of the door it shrank 2 inches.
--
Steve

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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] Corrosion [message #276286 is a reply to message #276224] Mon, 20 April 2015 10:40 Go to previous messageGo to next message
thesmith is currently offline  thesmith   United States
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How did they do it on the later coaches? Are they "better"?


Pete




roy1 wrote on Sun, 19 April 2015 14:08
Peer Oliver Schmidt wrote on Sun, 19 April 2015 11:47
Hi,

as can be seen from http://possy.de/corrosion.JPG the black thingie
around on the drivers and passengers side with the position lights in
it, seems corroded.

Anyone has a BTDT (preferable with pics) on what to do to get rid of this?

Please ignore my parking skills Wink
--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA
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. That is common in 73 to early 76 coaches the stainless rub rail wears thru the paint and the aluminum side corrodes . You would need to remove the rub rails sand and etch the damaged aluminum use body filler and finish sand then repaint when putting the rails back on and use some kind of tape to insulate the rail and keep it from rubbing thru the paint again would be helpful.




Cary, NC 1978 Center Kitchen Royale.
Re: [GMCnet] Corrosion [message #276288 is a reply to message #276286] Mon, 20 April 2015 10:58 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Sent from my iPad

On Apr 20, 2015, at 09:44, Pete Smith wrote:

> How did they do it on the later coaches? Are they "better"?
>
>
> Pete
>
>
>
>
> roy1 wrote on Sun, 19 April 2015 14:08
>> Peer Oliver Schmidt wrote on Sun, 19 April 2015 11:47
>>> Hi,
>>>
>>> as can be seen from http://possy.de/corrosion.JPG the black thingie
>>> around on the drivers and passengers side with the position lights in
>>> it, seems corroded.
>>>
>>> Anyone has a BTDT (preferable with pics) on what to do to get rid of this?
>>>
>>> Please ignore my parking skills ;)
>>> --
>>> Best regards
>>>
>>> Peer Oliver Schmidt
>>> PGP Key ID: 0x83E1C2EA
>>>
>>> '76a Eleganza II, VA
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>> . That is common in 73 to early 76 coaches the stainless rub rail wears thru the paint and the aluminum side corrodes . You would need to remove
>> the rub rails sand and etch the damaged aluminum use body filler and finish sand then repaint when putting the rails back on and use some kind of
>> tape to insulate the rail and keep it from rubbing thru the paint again would be helpful.
>
>
> --
> Cary, NC
>
> No Coach yet but dicided it will be wet bath.
>
> _______________________________________________
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Re: [GMCnet] Corrosion [message #276290 is a reply to message #276286] Mon, 20 April 2015 10:59 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Senior Member
That rub rail covers the seam where the SMC lower panels join the aluminum
upper panels. All three materials have a different coefficient of expansion
and contraction. By intentional purpose the rub rail serves as an expansion
joint. The constant movement eventually wears through the paint on the
aluminum upper body, exposing the aluminum to the stainless steel rub rail.
Corrosion then occurs. Complicated fix, several methods out there, none
perfect or forever. Got to get rid of any corrosion. Protect the aluminum
from further corrosion. Isolate the dissimilar materials. Paint to match.
Your methods might vary. Peter Huber had an aluminum or stainless steel
side molding made without the rubber strip. Highly polished and extremely
well fitted to the coach. Some of the best work I have seen. Others have
completely removed the rub rail and filled in the seam. I never have seen
one like that that did not crack after a few years. Like I said, no perfect
solution.
Jim Hupy
Salem, Oregon
78 GMC ROYALE 403
On Apr 20, 2015 8:44 AM, "Pete Smith" wrote:

> How did they do it on the later coaches? Are they "better"?
>
>
> Pete
>
>
>
>
> roy1 wrote on Sun, 19 April 2015 14:08
>> Peer Oliver Schmidt wrote on Sun, 19 April 2015 11:47
>>> Hi,
>>>
>>> as can be seen from http://possy.de/corrosion.JPG the black thingie
>>> around on the drivers and passengers side with the position lights in
>>> it, seems corroded.
>>>
>>> Anyone has a BTDT (preferable with pics) on what to do to get rid of
> this?
>>>
>>> Please ignore my parking skills ;)
>>> --
>>> Best regards
>>>
>>> Peer Oliver Schmidt
>>> PGP Key ID: 0x83E1C2EA
>>>
>>> '76a Eleganza II, VA
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>> . That is common in 73 to early 76 coaches the stainless rub rail wears
> thru the paint and the aluminum side corrodes . You would need to remove
>> the rub rails sand and etch the damaged aluminum use body filler and
> finish sand then repaint when putting the rails back on and use some kind of
>> tape to insulate the rail and keep it from rubbing thru the paint again
> would be helpful.
>
>
> --
> Cary, NC
>
> No Coach yet but dicided it will be wet bath.
>
> _______________________________________________
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>
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Re: [GMCnet] Corrosion [message #276292 is a reply to message #276279] Mon, 20 April 2015 11:21 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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As I remember there is a thin aluminum strip between the stainless piece and the plastic exterior piece that may be waisted away . If these parts are original pieces new replacement parts should be installed. Covering the back side of the stainless pieces with tape before re attaching will stop it from happening again. I know it happened to me on one side. I used the tape on the other side and it didn't happen again on that side.

Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Corrosion [message #276296 is a reply to message #276279] Mon, 20 April 2015 12:31 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Am 20.04.2015 um 16:18 schrieb Peer Oliver Schmidt GMC:
> Rob,
>> [..]I slid the new strip [..]
> where did you get the new strip from? Applied? If yes, do you have
> direct link (I couldn't find it...)
>
Is this the one: http://appliedgmc.com/prod.itml/icOid/1543

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA

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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Corrosion [message #276309 is a reply to message #276280] Mon, 20 April 2015 15:22 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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USAussie wrote on Mon, 20 April 2015 09:17
Steve,

I used the old piece I had removed from the driver side on the passenger side and did the same thing but that didn't shrink.

Regards,
Rob M.



I suspect the piece you moved was already done shrinking. Fortunately I had more rubber strip available so I only had to put a spliced on piece on the LH side.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Corrosion [message #276320 is a reply to message #276309] Mon, 20 April 2015 17:29 Go to previous message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
Steve,

Yep, that's why I used it on the sections behind and in front of the entry door. I still left some extra before I cut it off.

It appears that it NEVER stops shrinking!

For those of you with the later coaches that use the adhesive backed stuff does it shrink as well?

Regards,
Rob M.


-----Original Message-----
From: Steve Southworth

I suspect the piece you moved was already done shrinking. Fortunately I had more rubber strip available so I only had to put a
spliced on piece on the LH side.
--
Steve

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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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