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rear window sealant

JRo

Well Known Member
Where do I get this fuel tank sealant for the rear window? I have some "pro seal" but it's clearly not workable enough to lay a thin bead.

Thanks,

Jim
 
Just curious. Why would you want to use pro-seal as opposed to clear RTV? My painter laid down two masking tape lines to define a 1/8" gap between them at the edge of the plex and laid in a bead of RTV. They smoothed it and pulled up the tape to give a clean great looking seal.

I really hate working with pro-seal, and unless it is required for fuel tank sealing I don't use it. Maybe I just have a unique resistance to it,but so far so good!
 
For that feeling of accomplishment!

Just curious. Why would you want to use pro-seal as opposed to clear RTV? My painter laid down two masking tape lines to define a 1/8" gap between them at the edge of the plex and laid in a bead of RTV. They smoothed it and pulled up the tape to give a clean great looking seal.

I really hate working with pro-seal, and unless it is required for fuel tank sealing I don't use it. Maybe I just have a unique resistance to it,but so far so good!

I more-or-less followed Van's SB instructions, using the specified Devil's Snot. Plenty of over-masking needed, of course. I loosened all the screws enough to wedge two layers of popsicle sticks between the polycarbonate and the turtledeck, loaded up a small syringe (without needle) with the evil snot, and positioned my favorite wife cross-legged in the back with socket wrench in hand to do the tightening as I gooped things up from one side to the other. From inside, she was able to monitor that the bead spread out properly when the screws were tightened. The snot is so viscous that it took considerable muscling to push a bead out of the syringe, so the entire process took close to an hour.

I don't know if replacing the devil's snot with RTV will work chemically or not--but it would have been a lot easier to squeeze in.
 
I have been told for many years that RTV/Silicone sealants will cause corrosion when used against aluminum. I really think Van's knows what they are talking about regarding this.
 
I have been told for many years that RTV/Silicone sealants will cause corrosion when used against aluminum. I really think Van's knows what they are talking about regarding this.
Another question I would have before making this decision is whether or not RTV/silicone is fuel resistant. Part of the reason we're doing this sealing is to protect the exposed edge of the window material from fuel - this is where the crazing comes from when fuel gets splashed onto the window. I'm pretty sure Pro-Seal will protect that edge, not so sure about RTV or silicone.
 
All the RTV / gasket maker products I am familiar with specifically say "not fuel resistant".
Though it would have made for easier installation, that is specifically why it was not specified.
 
You guys may be right about the fuel effects, but I haven't had any problems keeping the fuel off my window during fueling. My concern about smearing pro-seal or RTV between the plex and turtle deck surfaces is that it might make window replacement problematic if I ever have to put in a new rear window. The thin bead on top of the plex at the edge of the turtle deck looks good and keeps the rain out. The painters used a light grey RTV which may be fuel resistant, but so far so good!
 
sealant

The RV6 I had was sealed with a grey sealant I thought was pro-seal because of the color and consistency. The painter did it, I didn't know he was going to, but the entire canopy, tip-up front and back window, was sealed. He did a really good and neat job, and I thought it gave it a good look and finish.
 
Thinning Proseal

I make no statement as to whether this is a good use of proseal and I would certainly not use it as the primary way to seal the fuel tanks but proseal can be thinned with MEK. I have used it to paint over the tops of rivets that were otherwise sealed with straight proseal and to force into "loose" gas tank rivets. I will say that it "seems" to make no difference in the proseal in the long run. I mix about a third or more into the proseal (it takes a fair amount) and then us an acid brush to paint it on. It will require a bit of mixing before it suddenly goes into solution.

It does not seem to delay the drying time of the proseal appreciably but I have added additional MEK as the mixture starts to set up and it will remix just fine and further extend the working time. Again, I make no statement as to whether this is a good idea in the long run but is is a good way of making Proseal more workable and as a topping coat. I'm not sure about getting MEK in any form near Plexi, which is a separate issue.

In another project, I built my RV-10 wing tanks about four years ago and have had fuel in them for about a year with no issues so far. The MEK (substitute) that they now sell seems to work as well if not a little better than the original formula is this application. I have not tried the Industrial solvent that they now sell in place of MEK.

I have used the Proseal/MEK mixture successfully to seal gas tank weeping rivets. Place a rubber grommet over the leaking rivet with an inside diameter slightly larger than the rivet head. Fill the grommet with the thinned Proseal and hold a flat piece of aluminum (say .050 or thicker) on top of the grommet. Strike the aluminum piece with a mallet to force the mixture into the rivet opening. It takes more than just a light tap, be fairly aggressive with the mallet. I generally repeat the process two or three times just to make sure. Good luck.
 
If you want to lay a thin bead, but it in a heavy duty zip lock, cut off a tiny corner, and squeeze the thing. You may be amazed
 
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