Pro Seal shelf life??

[jdmunzell]

I ordered some new Pro Seal last year and the currently un-opened batch has a posted shelf life of May 2014. It has also been sitting in my air conditioned workshop/basement at a constant temperature of around 74 degrees. Events arose of the past months and I was not able to assemble my right fuel tank until now. This being the beginning of August 2014, would I still be safe in using this or should I order a new batch?

I would think a couple months past date in climate controlled environment it would still be OK.
Mix up a small batch, see how it behaves.
When I resealed my Mooney tanks I used expired sealant I got for free from Hawker.

[cajunwings]

Would probably work just fine, but for me I personally would use fresh pro seal on the tanks. Anything to head off trouble later. Last week I bonded some non critical parts with proseal that was expired about 24 months, took a little longer to cure but worked well enough.

Don Broussard
A&P, IA, ATP
RV 9 Rebuild in Progress

[DonFromTX]

I keep mine in the fridge, somewhere I thought I had heard that it will last almost forever if kept cold.

[aturner]

Unopened containers that are just a couple of months over their shelf life? I wouldn't blink an eye at using it, but that is just me. I'm still using a can of proseal and hardener left over from my fuel tanks for misc. gluing jobs, and it must be five years out of date, with containers that have been opened and closed countless times. Still sets up.

[vfrazier]

I would use fresh ProSeal on the tanks, but old ProSeal is useful elsewhere for a hundred different things.

I have a 12 year old can from building my Rocket in the shop fridge. I take it out regularly for spot jobs and it performs just like new as far as I can tell.

I am currently using it to seal holes in my RV-6 firewall, seal down the edge of the heatshield mat insulation, and plan to use it for the canopy to frame adhesive (with rivets too). It eliminates canopy squeaking, but I'd not claim it to retain the canopy bubble in flight.... I'm not that brave.

YMMV!!

[gmpaul]

I just used my Proseal, 13 months old it was starting to get stiff but worked fine. Like others have said store it in refg or freezer and it will last. Found out about cold trick the a few months ago.
G.P.

[plehrke]

Originally Posted by cajunwings

Would probably work just fine, but for me I personally would use fresh pro seal on the tanks. Anything to head off trouble later. Last week I bonded some non critical parts with proseal that was expired about 24 months, took a little longer to cure but worked well enough.

Don Broussard
A&P, IA, ATP
RV 9 Rebuild in Progress

Exactly what Don said. Just bonded parts last week with 2 year old proseal and cured fine but would not use old proseal to seal a fuel tank. To much trouble if found out later it did not seal properly.

[vfrazier]

Just to reiterate in case some overlooked my point...

I keep my 12 YEAR old ProSeal in the shop fridge (not the freezer) and it is still quite useful.