Sili-cant

If the +SIL is sandwiched between two impervious layers of coated sil it may take a while…

Is there a smear of +SIL that is exposed to the air? And is it also Not curing?

What is your temperature and humidity?

Never used the Gear Aid version but standard silicone dries faster in high humidity.

I have used a steam cleaner (at a distance) to cure some seam sealing for urgent jobs.

You can wipe off drips with Coleman fuel/white spirit or mineral turpentine (the type used to clean paint brushes from oil paints)

Seam grip is for PU coats.  Seam grip + sil is for sil coats.  What are the coats on the reinforcement fabric and the fabric being reinforced?  If the sil sealant is being applied to PU or other non-sil coats on either fabric, there will be not much of a bond..  The best bonds are Seam Grip to PU coats, or the PU side of the popular fabrics that now have sil coat on one side and PU coat on the other.  There is a BPL article about bonding sil to sil with sil glues, (not sil sealants) like GE sil glue, and you do get a bond, but it has much lower peel resistance than the PU to PU bonds. which are awesome. Suggest using one of the new sil/PU coated fabrics, and seam grip to bond the sides that are PU coated, and use sil sealer only for the sides that are sil coated.  One such fabric is Rockywoods 7D.  Also, even though the sealants are viscous (thick), the layer of sealant or adhesive should be thin to get a good bond, which takes some work.  I use popsicle sticks.

I missed the sil poly bit…

my comment was about silnylon to silnylon.

@scfhome referred to (maybe?) this article:

MAKE YOUR OWN GEAR: SEALING SILNYLON SEAMS

Getting silicone sealants to dry can be tricky. Someone mentioned that sandwiching it between two WP layers can cause some drying problems, and letting it get cold (freezing) can ruin it before setting. Usually, it needs access to warmth and humidity to break down a chemical inhibiter in the caulk letting it harden. Old sealant can go bad just sitting in an unopened tube because the inhibitor breaks down over time. It should smell like vinegar when used. Using mineral spirits/WG will effect drying times much.
Anyway, it sounds like you might have gotten a bad tube. You can try to remove this with mineral spirits and let it dry completely before trying again. You really shouldn’t try to use the seamgrip+sil on the next coat, though. Any remaining stuff in/on the fabric will cause a loose bond. Likely your best bet would be to sew these on and seal any seaming after. This is only a guess, though.

Thanks for the replies everyone. Sorry to leave such a negative post. The frustration got to me a bit. The seam grip+sil is sandwiched between two 1.1oz silpoly. I had it sitting in my basement, which likely increased the problem of it not drying. I’m going to use Franco’s idea of  the steam cleaner since I have one already. Fingers crossed!

Ryan,
The article I was referring to was by Jim Colten, published in BPL in 2010:

https://backpackinglight.com/myog-laminating-silicone-impregnated-fabrics/