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simple sanctuary · 04-19-2014, 10:22 PM

Hello good folks~

Needing some advice on what sealant to use in various places as I renovate my first ever Airstream, an 81 Excella II which has plenty-o-leaks (though the seller said there were none, ha ha). I've read/heard various suggestions and honestly I'm confused.

I understand I need to remove old sealant first, not to use silicone, and that taping will help with a clean line. I saw that Vulkem is best for the roof and over the tops of the windows and doors and Parbond is good for seams and sides of windows. Then someone who repairs Airstreams for a living shared they use Trempro for everything (looks like that's the new version of Vulkem). And someone else I talked to swears by Elastomeric.

I don't want to mess up with such a big job and appreciate your support. What would you recommend for the following locations:
-around roof vents
-over windows and doors
-along seams on side
-around lights
-at the bumper (where a lot of water is moving in)
-any other key locations I'm missing...

Thanks tremendously!
Kim

batman · 04-20-2014, 01:00 AM

Kim,
There must be quite a few threads on sealants here on the forum.
However I would remove all of the old sealants from all seams with a plastic scraper or a piece of cow hoof you can get from the pet store, it will not scratch the aluminum.
Then reseal every seam and rivet head with Capt. Tolley's Creeping Crack Cure, It will wick into the seam like no other product I know of and dry's clear. It is the best for fine seams and rivet heads because of its wicking action.
After you have sealed every seam and rivet head with Capt. Tolley's then reseal the large gaps with Trempro 626 and Parbond on the rest of the smaller seams.
Trempro is gray, Parbond is silver/aluminum.

My 2 cents
-Dennis

dznf0g · 04-20-2014, 06:28 AM

What Batman said. Except I use Tempro 635 on the large seams. Eyebrows, gutters, etc. Capt. Tolleys is great stuff. For the roof openings, I went with Eternabond tape last time instead of sealer. Still use the Tempro on the TV antenna, Radio Antenna, and bath fan and tank vent.

I found quite a few rivet leaks with Tolleys this spring. I use Parbond on seams with 1/16" or less gap and Tempro on anything larger.

Take the time to tape everything off with painters tape for a professional looking job. Definitely worth the effort.

r carl · 04-20-2014, 08:15 AM

Trempro 644 is the one to use I think.

HiHoAgRV · 04-20-2014, 08:42 AM

I've switched over to only using Tempro. It sticks like crazy and stays flexible. In my experience, Parbond makes a nice line, flows well but after a year or so, cracks and leaks.

On the really small joints, I tape each side and work in the tempro. For removable items like clearance lights, I tape around them, remove the light and put tempro on it's base. reinstall and clean up the mess (thats where the tape really helps!!!)

After several years on a couple of trailers it has worked very well for me.

TinTin · 04-20-2014, 08:59 AM

The last post in this thread has a list of sealants:

http://www.airforums.com/forums/f44/...ry-116214.html

r carl · 04-20-2014, 10:47 AM

Quote:

Originally Posted by hihoagrv

i've switched over to only using tempro. It sticks like crazy and stays flexible. In my experience, parbond makes a nice line, flows well but after a year or so, cracks and leaks.

On the really small joints, i tape each side and work in the tempro. For removable items like clearance lights, i tape around them, remove the light and put tempro on it's base. Reinstall and clean up the mess (thats where the tape really helps!!!)

after several years on a couple of trailers it has worked very well for me.

x2.

Larry C · 04-20-2014, 11:19 AM

I'm not familiar with Tempro, but I've had excellent results with EternaBond for roof vents. I bought two rolls of th 5" wide, it's been on for 2 years, not a problem.
Larry

dznf0g · 04-20-2014, 11:30 AM

Hmmm, except where there is moderate movement between surfaces (like battery opening frames to skin) I've noted Parbond outlasting Tempro by 2 times, roughly.

Perhaps climate??????

Inland RV Center, In · 04-20-2014, 12:58 PM

Quote:

Originally Posted by simple sanctuary

Hello good folks~

Needing some advice on what sealant to use in various places as I renovate my first ever Airstream, an 81 Excella II which has plenty-o-leaks (though the seller said there were none, ha ha). I've read/heard various suggestions and honestly I'm confused.

I understand I need to remove old sealant first, not to use silicone, and that taping will help with a clean line. I saw that Vulkem is best for the roof and over the tops of the windows and doors and Parbond is good for seams and sides of windows. Then someone who repairs Airstreams for a living shared they use Trempro for everything (looks like that's the new version of Vulkem). And someone else I talked to swears by Elastomeric.

I don't want to mess up with such a big job and appreciate your support. What would you recommend for the following locations:
-around roof vents
-over windows and doors
-along seams on side
-around lights
-at the bumper (where a lot of water is moving in)
-any other key locations I'm missing...

Thanks tremendously!
Kim

You can use Vulkem, Sikoflex or Parbond.

Vulkem is heavy duty, slow dry.

Sikoflex is heavy duty, fast dry.

Parbond is light duty, basically for small seams, and moderate drying time.

Andy

Lance M · 04-20-2014, 01:38 PM

I think Parbond is useless. Maybe it is climate, but I agree with HiHo about Parbond. I have used and tried every sealant I can get my hands on and have narrowed my use to two 3M products; 540 gray and 5200 white.

dznf0g · 04-20-2014, 02:39 PM

Let me be clear relative to my use of Parbond. I ONLY use it for seams between skin and mounted items....like water inlet doors, Running lights, Electrical inlet, etc. Basically where I have a solid accessory to skin, very thin sealing seam. I don't use it for lower rub molding, gutters/awning rails, etc. where there are wider gaps subject to relative motion between panels. It is basically used for visible seams on the vertical panels which was originally sealed with Acryl-R. I think Parbond color looks better. However, I would never use parbond nor Vulkem on panel edge seals...only Acryl-R.
For those applications, I find Parbond excellent.

simple sanctuary · 04-20-2014, 10:58 PM

Wow, thanks everybody! I guess in the end, I won't know (let alone, form a strong opinion) until I try.

Traveling to Out of Door Mart tomorrow (about a 75-minute drive without my trailer--I don't have a tow vehicle anyway) to get some supplies and will try to pick the service folks' brain. Also hope to get tips on which seams really need sealing (wish there was a diagram somewhere which highlighted them)…like, do the vertical seams really need to be caulked? And, if I'm not missing any rivets, do I need to seal over them?

Sounds like Trempro 635 might be a good bet for the bumper (not a particularly big gap there but it is a vulnerable and actively leaking area).

Had not heard of "eyebrows" (area over the windows?) nor rub rails (maybe same as "belly band"?)…thanks for ever an expanding Airstream vocabulary.

**blmitch5** · 04-21-2014, 06:25 AM

Out of Doors Mart is very friendly and helpful. They will help you out.

dznf0g · 04-21-2014, 06:36 AM

rub rail = belly band and/or beltline molding.
Typically, the skin seams (where two sheets are riveted together) are sealed with Acryl-R and, if done well at the plant, don't leak for quite a few years. Eyebrows (rain gutters) over doors and windows are notorious leakers, both from rivets installed over rivets as well as the sandwiched aluminum material involved. Awning and rain gutters are also frequent reseal candidates, followed by rivets in general, awning mounting hardware and window glass.

At least that's my experience.

perryg114 · 04-21-2014, 06:58 AM

I tend to like the Parbond but I don't live in Texas. The Parbond is much more flexible and will run into cracks around window frames. In places where stuff flexes and there is relative movement is does a better job. I have used Parbond and then put Trempro over that. I use them both. I have had more problems with the Trempro cracking than the Parbond. I put the Trempro on some skylights and it lasted about a year then got hard and cracked.

Perry

dznf0g · 04-21-2014, 07:33 AM

Perry and I experience the same results. There are two areas where I haven't found a great solution. Both are from front end flex. Before I go on, let me say I am confident I don't have abnormal movement in the front end. The frame is healthy and I have never had a popped rivet in the front anywhere. It is normal (and needed) to have some A-frame flex while going down the road. But there is some movement transferred to the front end skin from flex. I have the inner batt box door frame edge where the skin has a tendency to oil can a tiny bit relative to the box door frame. This eventually leads to a break in sealers between the skin and the bead of sealer. I drove very small screws, from the inside, clamping the skin to the door frame and cured the curbside, but the streetside still separates

The other area is the lower inboard corner of the pano glass. The glass is not sandwiched to a frame, but rather is just glued (with Vulkem) into the inner surface of the outside frame. Over time, flexing in that area opens the seal in the lower inboard corner. I have tried digging out as much vulkem, from the outside as I can (about 1/16" and covering with new vulkem or Parbond. Both reseals only last about 2 years, and is only an "umbrella" over the separation of sealer and glass. This spring I am trying Tolleys as it wicks down all the way and fills the entire separation. We'll see.

batman · 04-21-2014, 07:08 PM

One more quick comment. I have noticed some discussion about the type of TremPro we are using 626, 635, 644, etc.. For example 626, and 636 are Polyurethane sealants, 644 is Silicone. Here is an excellent pdf breakdown on all the TremPro product from Fastenal. Check it out. http://www.fastenal.com/catalog_pages/2007/4-67.pdf

perryg114 · 04-21-2014, 07:34 PM

I used Trempro-635. 626 is supposed to be the original Vulkem formula. Both are urethanes.

Perry

reinergirl · 04-21-2014, 08:16 PM

Quote:

Originally Posted by dznf0g

Perry and I experience the same results. There are two areas where I haven't found a great solution. Both are from front end flex. Before I go on, let me say I am confident I don't have abnormal movement in the front end. The frame is healthy and I have never had a popped rivet in the front anywhere. It is normal (and needed) to have some A-frame flex while going down the road. But there is some movement transferred to the front end skin from flex. I have the inner batt box door frame edge where the skin has a tendency to oil can a tiny bit relative to the box door frame. This eventually leads to a break in sealers between the skin and the bead of sealer. I drove very small screws, from the inside, clamping the skin to the door frame and cured the curbside, but the streetside still separates

The other area is the lower inboard corner of the pano glass. The glass is not sandwiched to a frame, but rather is just glued (with Vulkem) into the inner surface of the outside frame. Over time, flexing in that area opens the seal in the lower inboard corner. I have tried digging out as much vulkem, from the outside as I can (about 1/16" and covering with new vulkem or Parbond. Both reseals only last about 2 years, and is only an "umbrella" over the separation of sealer and glass. This spring I am trying Tolleys as it wicks down all the way and fills the entire separation. We'll see.

I'm unfamiliar with the design of the battery box but is it possible to pull the frame and back it with a strip of eternabond doublestick tape and rivet/ screw it back on? I am amazed at how pliable and elastic the stuff is more than a year later ....