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Fuel tank sealant in cooler months

I ordered fuel tank sealant from Vans in the summer with the intent to finish while it was still warm out, but that didn't happen.

Where I'm at, the high is 44F and the low is 37F, and will trend colder - my garage is not insulated, but I installed a 240V hardwired electric heater last year which keeps it warm enough that I can work at night. I usually don't run the heater all the time. I don't have a thermometer out there to see how warm it actually gets with the heater.

The sealant is stored indoors at room temperature. The sealant expires in May 2022 I think. Should I just wait until spring?

I could also mix the small amounts I need inside, apply it in the garage, then bring the parts and/or tanks inside to let them cure. I don't think building inside altogether is an option.. the fam won't like the acetone and sealant smell, nor the noisy compressor... needs to be kept clean and that cats won't allow that, but I could store in a closed room while it cures.

Probably easiest to wait for spring and hope for a warm week. Or just selling the sealant I have and getting more next spring to restart the clock.

Sincerely,
Poor Planning
 
There are several ways to go...

1) Put the sealant in the fridge or freezer and build the tanks next spring.

2) Build the tanks in your garage, and let them cure naturally in the cool weather. Proseal eventually cures, so no harm should come from this approach. It'll just take a lot longer than if it was 80F in your garage.

3) Build the tanks in your garage and find a warm place to store them for a few days so they cure relatively quickly. For instance, you could bag them and put them in a spare bedroom.

All three methods will work and there are probably a few others that would be just as good. This is one of those situations where you have several paths to success - you just need to commit to one.
 
I just ordered some sealant from vans will be here next Monday, depending on the expiration date I would trade you cans, if that would help you out.
 
I am actually in favor of cooler temp for the tank sealant since it gives a longer period of time to work with it. Once it is applied, it will cure just fine only takes longer. If you want to speed up the cure time, just build a small area in your garage (put some blanket over the tank and a lamp). Especially when you get to the baffle portion, the longer working time with the proseal is a plus. I waited for a cooler day to do that part and now in a waiting stage to let it cure.
 
Just for another data point on cool curing, I built my tanks in a cool basement. Pictures show us wearing sweatshirts. Proseal balance and well mixed. My memory says it took more than a week before it would not take a fingerprint. Might have been 2 weeks but well, y'know how memory is. Leakless for 15 years.

And yes the freezer is your friend for extending pot life and storing unmixed.
 
Thank you all, and thank you, Jslow2, for the very kind offer.

I'm not so concerned about time to cure, I'm more concerned about the quality of cure/seal. Sounds like it will cure OK in the cold. I don't see a min temp. on the spec sheet, only that it must be stored below 80F. So I'll forage ahead given that I'm at the final stages of scuffing, cleaning, dimpling, cleaning again, then assembly. I plan to mix inside, then apply and rivet in the garage and bring the parts inside nightly. I think if stored in the right place the fam won't notice the sealant aroma :).

Thanks again!
 
You could store & mix sealant at room temp, than do the work outside. Wouldn't be hard to put together a plywood enclosure (or similar) over the tank for over night heated by a small electric space heater ($30 at Home Depot or similar) to keep it warm when not working on it. Heater could be used to keep you warm too while working on it.
 
Add a little water to Pro Seal makes it cure faster...

Hi all:

Some sealant tips from the corporate jet world...

1) Add a tiny bit of water to help it cure faster - we used to spit in the mix - gross, I know!

2) When you pull off the masking tape, use KY on your gloves - this avoids the giant ball of pooky tape you can't get off your gloves syndrome.

3) Use ONLY plastic scrapers to remove sealant and sharpen them constantly - we used old Learjet windshield pieces.


Regards,
James
 
Shelf life

I wouldn't worry too much about exceeding the shelf life by a little bit. It is common in the aerospace industry to re certify adhesives that have expired with a 6 month shelf life extension. Some materials wont extend, but Proseal seems to last forever, so i would not be hesitant to use Proseal 6 months past shelf life. Heck i have stuff 4 years past shelf life that I am using to seal up firewall; mixes fine, and cures just as slow as the fresh stuff in 50F weather. :)
 
Proseal life

Well, I've had some in the freezer for about the last 10 years. But, it sat on an open shelf for the first 15 years in my Mechanic shop. So, it is at least 25 years old. Both catalyst and Proseal.
Took it out last fall to test it.
Mixed according to directions. I seemed to set up just as fast as the 5 year and 6 month old stuff
Stuck like @&%& on my test pieces.
Now that said. I have the 6 month old stuff for the tanks I built.
I want and buy new for tank building.
But, that said. It seems to last a long time. If you are gluing stuff together or just sealing a crack or what ever,
I'm gonna keep the old stuff in the freezer for awhile longer.
See how it goes in 10 more years. Ha Ha Ha.
Art
 
Aside from the storage question, the one issue I've had with using the proseal in the cold is how stiff it is while mixing, and after. I started working on my first tank when it was about 30 degrees in the garage. The working time is a definite plus, but when the sealant is that cold (even after it was warmed up inside, it didn't take long to get very cold again in the garage), it doesn't flow well. I found that it was a little harder not to get air pockets while applying it to parts, and it definitely didn't squish out from under parts as easily as it did when it was warmer. In the end, I decided to wait until it's just a touch warmer to finish things up. I'd still take colder over hotter, but I've moved on to other things for now and will come back to the proseal when it's just a bit easier to work with.
 
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