Originally Posted by Frank
I rebuilt (well, tried) my 750 Holley because 1 backfire up through the old Holleys would blow out a power valve. Sometimes floats stick, sliders get stuck, you get vacuum leaks, jets clog, bowls leak, etc...
I've rebuilt my Holley 650 a few times. When I first got it I remember I think drilling and putting some type of screw in w/ a floating ball that kept the power valve from blowing. Maybe someone knows more, I can't remember it was so long ago when I put that in. But it works.
But as far as rebuilding, I've used BG's rebuild kit each time and never had a problem. It includes everything I needed. As far as the signs, spray it down w/ carb cleaner first, and look for leaks. I don't see how it could ever hurt to rebuild it if its been a long time.