rubber tape

[jonyyuma]

Electrical heat shrink tape is available on a roll, or buy it in tubes to slip over and heat.

 

[Soundguy]

Our maintenance guy at work uses a lot of liquid electrical tape. I haven't really used it, but he swears by it. You might try that.

i , many times will liquid e-tape a connection, then put heat shrink over it.

works good.. especially if you di it when it's still wet, makes a good water tight seal.

soundguy