3M Super Weatherstrip is an old favorite, black or yellow. When an old mechanic says "gorilla snot", he means 3M yellow.

Pliobond is another classic.

http://0363d88.netsolhost.com/WordPress/wp-content/uploads/2012/09/Pliobond-info-sheet.pdf

I use both, but tend to buy the 3M black for a one-shot job to get a fresh tube. Pliobond is less viscous and has a brush cap in the small cans. Shelf life after opening is better with Pliobond, and the packaging allows stirring and thinning with MEK.
 
3M Super Weatherstrip is an old favorite, black or yellow. When an old mechanic says "gorilla snot", he means 3M yellow.

Pliobond is another classic.

http://0363d88.netsolhost.com/WordPress/wp-content/uploads/2012/09/Pliobond-info-sheet.pdf

I use both, but tend to buy the 3M black for a one-shot job to get a fresh tube. Pliobond is less viscous and has a brush cap in the small cans. Shelf life after opening is better with Pliobond, and the packaging allows stirring and thinning with MEK.

Dan is exactly right; I prefer the yellow but also have black in the box. I keep Pliobond at hand for crank nose seals. With the 3M product you have a little bit of wiggle room for positioning and alignment; with the Piliobond you need to be dead nuts "on" when you assemble the parts.