fuel filter in petcock?

when i removed my petcock it looks like there is a filter. I don't think it is but I thought i would ask

Technically, it is a fuel filter.
But since that filter can distort slightly where it fits into the top of the petcock, it can allow debris to bypass it and enter the carbs.
That's why a good portion of us have added an in-line fuel filter for our bikes.
You can find them at just about any auto parts store for a couple of bucks.

yea I keep buying them. know my petcock is leaking i think the line is backed up now. its not pinched. i dunno i've spend about 30hrs of work on the bike sense i bought it and I just want to drive it. is it pretty easy to rebuilt the petcock?

First off, why bike are we talking about here?
It would be very helpful if you had that info listed in your profile.

It's not that dificult to rebuild a petcock, and the rebuild kits are fairly cheap (about $30).
But from my experience of rebuilding several petcocks that continued to leak afterwards, is it's just better to buy a NOS petcock (about $35 ~ $90 depending on the brand/model you buy) and be done with it.

I have a 81 kz650 csi(H1)

the leak is coming form a spacer by where the fuel line connects. there is a pin hole there. is that suppost to be there? I've thought about jb weld. is that a bad Idea?