Vacuum bleeding questions. (Page 1/1) Tallguy68 JAN 06, 04:56 AM Learning to bleed brakes using a vacuum pump. The vacuum pump that I purchased will only create five on the gauge in the negative. I don’t know what the measurement is but is that high enough? I hope that makes sense. But I’m thinking it should be 10 to 15 whatever’s, so I’m wondering if I got a bad vacuum pump. Also, any tips on making sure to get a good seal on the bleeder while you’re bleeding the brakes? I’ve done the deal where you put the silicone grease around the base of the bleeder plug, but still seems like I’m pulling air from around the plug, not from the braking system. Any tips? (1988 GT) Larryinkc JAN 06, 10:20 AM I use Permatex Rubber Sealant to renew the sealant on the speed bleeders in my brakes and it works good. Clean the bleeder screw threads good and give it time to dry before screwing them back in.