The air is drawn in past the threads of the bleeder
Mityvac is good for drawing through a change of fluid but for final bleeding
For final bleeding clear plastic tube on the bleeder apply pressure to the brake open the bleeder let fluid come out close the bleeder then release the pressure on the brake
During the process watch the clear tube to see if there are any bubbles in the fluid once no bubbles top up the master cylinder
Care has to be taken when bleeding if the brake pads are part worn when topping up the master cylinder leave sufficient level of fluid to accommodate new brake pads otherwise next time you push the pistons in the master cylinder may overflow it is not good to get glycol based brake fluid on paint as it is a very good paint stripper
Brian
Mityvac is good for drawing through a change of fluid but for final bleeding
For final bleeding clear plastic tube on the bleeder apply pressure to the brake open the bleeder let fluid come out close the bleeder then release the pressure on the brake
During the process watch the clear tube to see if there are any bubbles in the fluid once no bubbles top up the master cylinder
Care has to be taken when bleeding if the brake pads are part worn when topping up the master cylinder leave sufficient level of fluid to accommodate new brake pads otherwise next time you push the pistons in the master cylinder may overflow it is not good to get glycol based brake fluid on paint as it is a very good paint stripper
Brian