Flyback with Missing Insulation

[DaveWM]

If it works I would leave it be.

Here is an example of flyback that works fine, not a predicta, but you get the idea.

If however you choose to redo the fly, I have heard that you have to be careful about what kind of silcone you use, to avoid chemicals in the product from attacking the fly.

From your description it does not sound bad enough to warrent fooling with.