Water leaks

[jim bounds1]

Wanted to bring up a subject: Water leaks!

Anyone who has watched the pressure test I use agrees that many leaks show
up that you would never think of and show some you though were OK. Even
with finding the se leaks there is never a guaranty that these are the only
ones there are and knowing them is only half the battle, now you have to
seal them.

I have had several instances recently that I feel compelled to talk about
this.

Because of the construction of our body, there are several flex joints
required. When you have different materials make up a skin, they will
react differently to the environment and flex differently as well.

These joints present a real challenge, gobbing them with gooey stuff does
not solve the problem. Lopping on more only makes a mess! You have to
understand the root of the problem and solve it. If the leak is caused by
lateral or sheer movement, you need to apply a product that will adhere to
the 2 nearby surfaces and shield the area that has to move and keep water
out. If the problem is adhesion of panels, a stronger adhesive on another
way to hold the panels together must be found.

You cannot expect one product or approach to seal all leaks and you cannot
expect guaranteed results every time.

Finding & sealing leaks is a real pain in the rear. It is especially
frustrating when you try the best you can and you still find leaks. It
makes you feel pretty useless, you did the work but the trouble did not go
away. It takes hours of testing, sealing & re testing and still leaks will
sometimes persist! If I charged for all the hours we take in looking for
leaks, the bill would be astronomical. I could not stay in business
sealing leaks alone, it always seems to be one of those loosing deals!

Those of you who have tight coaches, count your blessings. Those of you
that are in the hole here with me, take hart in knowing you are not alone!
There is no magic liquid but there are many people out there looking and
maybe someday a cure will be found.
Jim Bounds/Co-op Motor Works Orlando www.gmccoop.com

 

[gene]

Another part of the frustration is that things change. What once was
tight, now leaks. I was fine till this year, this last heavy rain now
shows me I have developed a leak somewhere that is running down the ceiling
liner and out an inside light

arggggg

gene

>Wanted to bring up a subject: Water leaks!
>
>Anyone who has watched the pressure test I use agrees that many leaks show
>up that you would never think of and show some you though were OK. Even
>with finding the se leaks there is never a guaranty that these are the only
>ones there are and knowing them is only half the battle, now you have to
>seal them.
>
>I have had several instances recently that I feel compelled to talk about
>this.
>
>Because of the construction of our body, there are several flex joints
>required. When you have different materials make up a skin, they will
>react differently to the environment and flex differently as well.
>
>These joints present a real challenge, gobbing them with gooey stuff does
>not solve the problem. Lopping on more only makes a mess! You have to
>understand the root of the problem and solve it. If the leak is caused by
>lateral or sheer movement, you need to apply a product that will adhere to
>the 2 nearby surfaces and shield the area that has to move and keep water
>out. If the problem is adhesion of panels, a stronger adhesive on another
>way to hold the panels together must be found.
>
>You cannot expect one product or approach to seal all leaks and you cannot
>expect guaranteed results every time.
>
>Finding & sealing leaks is a real pain in the rear. It is especially
>frustrating when you try the best you can and you still find leaks. It
>makes you feel pretty useless, you did the work but the trouble did not go
>away. It takes hours of testing, sealing & re testing and still leaks will
>sometimes persist! If I charged for all the hours we take in looking for
>leaks, the bill would be astronomical. I could not stay in business
>sealing leaks alone, it always seems to be one of those loosing deals!
>
>Those of you who have tight coaches, count your blessings. Those of you
>that are in the hole here with me, take hart in knowing you are not alone!
>There is no magic liquid but there are many people out there looking and
>maybe someday a cure will be found.
>Jim Bounds/Co-op Motor Works Orlando www.gmccoop.com
>
Genef -- 77PB/ore/ca
GMC MOTORHOME INFORMATION
mr.erf
http://www.california.com/~eagle/

 

[bdub]

Here's a little on going research for a cure.
http://www.gmcws.org/tech.htm

bdub

>Wanted to bring up a subject: Water leaks!
>
>Anyone who has watched the pressure test I use agrees that many leaks show
>up that you would never think of and show some you though were OK. Even
>with finding the se leaks there is never a guaranty that these are the only
>ones there are and knowing them is only half the battle, now you have to
>seal them.

 

[al chernoff]

Jim, and the receipient of your test.. what was wonderful is that some of them
I do not feel would cause much problem, but those that can pool and come in,
ie in the roof, or in the windows should be caulked. When you did mine, that
squirt bottle told quite a story. Since po had removed the pod, there were
lots of holes I had sealed when Tom Bradley and I did my new ceiling. Knowing
that they didn't leak after being sealed was great. Finding the lone one in
the front that always brought in a bit of water after a rain... when it
dripped down the center of the front seats was great also, as was finding that
it was not the running lights as suspected, but the one seam end on the
drivers side. plugging that one solved my rainy problems. The others ( the
multitude of others) will have to wait unitil the other 8,8094,234,234 things
get done.
al

> Wanted to bring up a subject: Water leaks!
>
> Anyone who has watched the pressure test I use agrees that many leaks show
> up that you would never think of and show some you though were OK. Even
> with finding the se leaks there is never a guaranty that these are the only
> ones there are and knowing them is only half the battle, now you have to
> seal them.
>
> I have had several instances recently that I feel compelled to talk about
> this.
>
> Because of the construction of our body, there are several flex joints
> required. When you have different materials make up a skin, they will
> react differently to the environment and flex differently as well.
>
> These joints present a real challenge, gobbing them with gooey stuff does
> not solve the problem. Lopping on more only makes a mess! You have to
> understand the root of the problem and solve it. If the leak is caused by
> lateral or sheer movement, you need to apply a product that will adhere to
> the 2 nearby surfaces and shield the area that has to move and keep water
> out. If the problem is adhesion of panels, a stronger adhesive on another
> way to hold the panels together must be found.
>
> You cannot expect one product or approach to seal all leaks and you cannot
> expect guaranteed results every time.
>
> Finding & sealing leaks is a real pain in the rear. It is especially
> frustrating when you try the best you can and you still find leaks. It
> makes you feel pretty useless, you did the work but the trouble did not go
> away. It takes hours of testing, sealing & re testing and still leaks will
> sometimes persist! If I charged for all the hours we take in looking for
> leaks, the bill would be astronomical. I could not stay in business
> sealing leaks alone, it always seems to be one of those loosing deals!
>
> Those of you who have tight coaches, count your blessings. Those of you
> that are in the hole here with me, take hart in knowing you are not alone!
> There is no magic liquid but there are many people out there looking and
> maybe someday a cure will be found.
> Jim Bounds/Co-op Motor Works Orlando www.gmccoop.com

 

[bob mclaughlin]

Jim,
I used to think there were only two cures for leaks, namely,
1. Ignore them.
2. Stay out of the rain.
Your e-mail adds one more way. Send your GMC and hoard of money to Jim
Bounds and keep him in business.
More seriously, mine leaks on my left knee when driving in the rain and in
the right rear. After trying to seal them several times I've decided to use
cure 1 above. Good Luck everyone.
Bob McL

- -----Original Message-----
From: owner-gmcmotorhome
[mailtowner-gmcmotorhome]On Behalf Of Jim Bounds
Sent: Wednesday, January 26, 2000 7:37 AM
To: gmcmotorhome
Subject: GMC: Water leaks

Wanted to bring up a subject: Water leaks!

Anyone who has watched the pressure test I use agrees that many leaks show
up that you would never think of and show some you though were OK. Even
with finding the se leaks there is never a guaranty that these are the only
ones there are and knowing them is only half the battle, now you have to
seal them.

I have had several instances recently that I feel compelled to talk about
this.

Because of the construction of our body, there are several flex joints
required. When you have different materials make up a skin, they will
react differently to the environment and flex differently as well.

These joints present a real challenge, gobbing them with gooey stuff does
not solve the problem. Lopping on more only makes a mess! You have to
understand the root of the problem and solve it. If the leak is caused by
lateral or sheer movement, you need to apply a product that will adhere to
the 2 nearby surfaces and shield the area that has to move and keep water
out. If the problem is adhesion of panels, a stronger adhesive on another
way to hold the panels together must be found.

You cannot expect one product or approach to seal all leaks and you cannot
expect guaranteed results every time.

Finding & sealing leaks is a real pain in the rear. It is especially
frustrating when you try the best you can and you still find leaks. It
makes you feel pretty useless, you did the work but the trouble did not go
away. It takes hours of testing, sealing & re testing and still leaks will
sometimes persist! If I charged for all the hours we take in looking for
leaks, the bill would be astronomical. I could not stay in business
sealing leaks alone, it always seems to be one of those loosing deals!

Those of you who have tight coaches, count your blessings. Those of you
that are in the hole here with me, take hart in knowing you are not alone!
There is no magic liquid but there are many people out there looking and
maybe someday a cure will be found.
Jim Bounds/Co-op Motor Works Orlando www.gmccoop.com

 

[jim bounds1]

[ADMIN NOTE - "Bounced" Rich Text, Jim ya' gotta' post in "Plain Text"
only. The junk in braces() below is why. Patrick]

JR,

Man , I could turn this post into a phone book!

I try to divide the openings I find into 2 categories:

ffff,0000,00001- NON stress
leaks- with these the opening is caused be
something not tightened down, a bad fit, naturally occurring holes,
missing parts, rotted away parts & holes from after market accessories.

Try to replace or install the missing parts, tighten up, or repair the
problem. Install closed end rivets in holes, plates over big openings
or
new parts where the old ones are damaged. Of course seal each repair.

If the sealer is inside away from weather & UV, I might use butyl calk
or
tape. This stuff stays soft and will fill in void especially under a
pressure fit situation. The trouble with butyl is that if it is exposed
to UV, it will dry out and get hard then flake off. It also breaks down
under repeated washings and petroleum products also break it down. It
will streak as it looses itself.

If the area is exposed and is visible, I use a high grade silicone
(clear
on painted colors, black on gasket seams). I use Dow Corning (yea, they
had to do something with that implant material!)#791 perimeter sealant.
It actually comes in several colors but I usually shock clear & black.
It can accommodate + or - 50% movement. I was introduced to this
product
by a friend & GMC owner Kelly. He is a lurker on the net and a very
knowledgeable man when it comes to water leaks- it is his business!

On out of the way surfaces but still open to weather (like the roof, I
use an elastic aluminized mobile home sealant. It is self leveling and
has UV inhibitors in it.

ffff,0000,00002 Stress related
failures- This is the tough area.
Gobbing stuff will not solve the problem and sometimes nothing will
repair it long term. The first step is to try to find a way to rebond
or
repair the damage done by the stress.

Pulled away panels may need to be riveted down and glued. I cut a hole
then bevel the edge to allow a rivet to come as close as possible to
flush when it is installed. I also use Sikaflex. This is a bonding
adhesive that really works well. I do not have faith (although the
company tells me to) that Sikaflex will do the job alone so I generally
rivet as will as glue. After the panel is back in place, you still may
want to use a sealant to top off the job.

In the case of rails, vents, etc. I have not made up my mind as to what
works best. SOP has been to bed rails with butyl, but I have seem good
men loose their life trying to make this system work. I am currently
trying the self leveling roof sealant under the rails. I am also trying
a silicone membrane material over the rail to span the moving joint
covering the problem area. School is still out on this idea, it is
rather expensive and only 2 out of 3 times this method has worked
sealing
the leak.

Now if you are painting the coach, the process changes. Use seam
sealer on any opening and on top of stress repairs as well. A thin coat
will expand with the movement and is paint able! Bigger holes can be
plated and seam sealed & riveted panels can have the rivets filled and
sanded smooth. As the windows and other gasket sealed components are
installed, you can add additional sealant under the seam to help with
the
seal.



All of this is very time consuming and even with all of this fuss, the
leak gremlins sit there and laugh at you refusing to stop! I tell
people
to be sure you have a couple of holes in the floor to let out any water
that still gets in as a precaution. They look at me a give a small
chuckle as if to say - cute.

I listen to everyone and am willing to try anything in the pursuit of a
dry coach!

I was just frustrated yesterday over several leak issues and the
frustration the customers had over them and needed to vent a bit.
Thanks
for your indulgence, I usually unload on my dog but it was so cold here
yesterday that I didn't have the heart on our predawn walk.

Sorry for getting so long winded, Gotta get back to work as many of the
netters here are waiting on their coach. To all of them, we are making
headway- really!

Hope this helps,

Jim Bounds

- ----------------

>Jim,

>

>What do you use to seal the water leaks you find? If more than one,
list

>what each is good for sealing. Thanks.

>

>JR Wheeler 78 Royale NC

>

>

Jim Bounds/Co-op Motor Works Orlando www.gmccoop.com