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Fuel tank sight window prep

Tony_T

Tony_T

Well Known Member
Patron
I am about ready to glue and screw the sight window into the tank, and am wondering if the smooth plastic of the window should be abraided where the sealant is applied? I have taken pains to deburr the edges to eliminate crack starters.

After reading all the posts about this window, I think I actually like the idea of a sight window if it can be made trouble free, which we don't really know yet. But the window has no moving parts, no chance of hanging up and giving false reads and has no protrusions in the baggage area.

Anyway, did anyone sand the perimeter of the window to prep for sealant or would that weaken it?

Tony
 
Tony_T said:
I am about ready to glue and screw the sight window into the tank, and am wondering if the smooth plastic of the window should be abraided where the sealant is applied? I have taken pains to deburr the edges to eliminate crack starters.

After reading all the posts about this window, I think I actually like the idea of a sight window if it can be made trouble free, which we don't really know yet. But the window has no moving parts, no chance of hanging up and giving false reads and has no protrusions in the baggage area.

Anyway, did anyone sand the perimeter of the window to prep for sealant or would that weaken it?

Tony
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Very possible without knowing exactly how you would sand it.

I suggest following the instructions.
The sealant is making a gasket and the screws are doing the job of holding it in place.
 
Replace old window

What is the best approach to replacing the old window in the fuel tank. Ours was done before the "stop work" came out. It now has cracks.

Is it best to go through the top and remove all the rivets or to attempt reaching from the front? Front seems easier to get into but along way from what has to be worked on. Top seems like a lot of work with almost 100 rivets to drill out and replace but good access to the window.

Suggestions?
 
RGaines said:
What is the best approach to replacing the old window in the fuel tank. Ours was done before the "stop work" came out. It now has cracks.

Is it best to go through the top and remove all the rivets or to attempt reaching from the front? Front seems easier to get into but along way from what has to be worked on. Top seems like a lot of work with almost 100 rivets to drill out and replace but good access to the window.

Suggestions?
Click to expand...

I think Marty & John are going through the top so they can install a marine fuel gage. If I have a problem with mine that is what I'm going to do. I'll block off the site gage entirely and use the marine gage.
 
Tony, I scratched mine a bit with scotchbrite pad on the outer quarter inch. In my opinion I don't believe that would cause a problem. Proseal likes a little something to hold on to.
BTW great photos on your a pilot install. Thanks.
Dick Seiders
 
RGaines said:
What is the best approach to replacing the old window in the fuel tank. Ours was done before the "stop work" came out. It now has cracks.

Is it best to go through the top and remove all the rivets or to attempt reaching from the front? Front seems easier to get into but along way from what has to be worked on. Top seems like a lot of work with almost 100 rivets to drill out and replace but good access to the window.

Suggestions?
Click to expand...

I have done it twice working through the access cover on the front with no trouble.
It is possible, but depends on the level of hand dexterity you have.
I applied sealant to the heads of a couple screws, inserted them in opposite corner holes and taped them in place. Laid the tank on its side. Applied sealant to the window and laid it and the reflector in place (but do not push it down hard). Install a couple nuts to everything together. Then stood the tank upright and installed the rest of the screws. Use the tightening of the screws to evenly squeeze the sealant.
 
I am still wondering about cleaning up the surface of the (new) galss where the sealant oozed out into the holes. Is there a safe solvent to use for the cured sealant, or is rubbing it off with a sharpened popsicle stick the only safe way to do it?

Second question - aside from the glass issue - is there any solvent that will dissolve the cured sealant where there is excess around some of the rivet heads and seams? I would like to make the tank look better cosmetically before priming/painting.
 
BigJohn said:
Scott,

Is there a solvent that is known to be safe to use on the new glass material?
Click to expand...

There might be but I am not aware of any. The biggest problem is that there really isn't a good solvent for tank sealant.
That is the reason for the recommendation to let it cure (not just for a day, really let it cure) and then scrap it off.
I think it comes off pretty easy if allowed to fully cure.
 
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Clarification

I was answering the second part of John's question. I thought you meant finger prints etc away from actual sealing areas. I wouldn't put lacquer thinner near anything I wanted to stay sealed. It works great for finger prints and gobs away from any actual sealing areas. Definitely not near the glass, if you are installing it. Sorry if confusion.

John Bender
 
Tank finish...

BigJohn said:
Second question - aside from the glass issue - is there any solvent that will dissolve the cured sealant where there is excess around some of the rivet heads and seams? I would like to make the tank look better cosmetically before priming/painting.
Click to expand...

My tank, and pictures of most others that I have seen, looks awful with sealant everywhere. Marty has a picture of his finished tank, he shot it with rattle can texture cover-up and it looks fantastic, see his May 2009 blog (http://martysrv12.blogspot.com/2009/05/finished-painting-canopy-frame-and-tank.html).
Also, the rear carpet kit will cover it up (except the sight window area).

Tony
 
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We are just building our tank now. On the advice of staff at Van's, we are using Naptha to prep the metal for sealant. It also works to clean up sealant weep, at least before it is cured. Naptha is a very clean, low residue, aliphatic hydrocarbon mixture, aka Coleman Fuel. Aliphatic hydrocarbons are a major constituent of any motor fuel, so it should not effect the glass any differently than fuel would. It is less toxic than lacquer thinner, Acetone or MEK. It's also a little less aggressive as a solvent, so it takes a little more elbow grease if you use it to clean up sealant.
 
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