If your Tyre was cracked? I'm not sure any kit would work properly, maybe the gunk? Assuming you mean the tyre was old and the rubber had perished?I used one of those puncture repair kits when I got my first ever flat tire while touring in South East England.
Used 2 entire bottles of those Motul Kits.
Suffice to say they don't work very well if at all in most situations. What I had were cracked tires with 2 tiny holes about 3mm wide, but they won't seal this.
I have used puncture kits multiple times during my tour and even in the city. Its easy to use, very reliable and I feel its a mandate to have one for your tubeless ones on long rides.Anybody used one of those plug kits for touring? Are they any good?
From my latest experience, I'll say, Stay away from Slime.i use slime in my tire's its worry free