edwardthomson51@yahoo.com 1 Report post Posted March 22, 2021 hey guys i need sine advuce,,,, 1970 mustang coupe all manual drum brakes....i replaced everything from master cylinder to lines ....etc...... now i have to put in the brake fluid for the first time (going with dot 5)....and need to know - which is the best way to bleed them....i plan on using a mityvac but should i gravity bleed them first (since evreything is empty) ...ill bench bleed the master first...but eveything from the line distributor to the wheel cylinders is empty........ i have never replaced a whole system before so i want to do it right the first time...... thanks ed Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted March 22, 2021 I've had good results starting with gravity bleed first, then final bleeding with a pressure bleed. 1 Mach1 Driver reacted to this Quote Share this post Link to post Share on other sites
edwardthomson51@yahoo.com 1 Report post Posted March 22, 2021 THANK YOU BOB I THINK I AM GOING TO BENCH BLEED THE MASTER....THEN GRAVITY BLEED AND THEN USE MY MIGHTY VACCUUM TOOL I BOUGHT......AND SEE WHAT HAPPENS... ED Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted March 22, 2021 Please do not shake the container of DOT 5: it is highly susceptible to entrained bubbles. Quote Share this post Link to post Share on other sites
TexasEd 188 Report post Posted March 22, 2021 I've found you have to finish with a manual bleed because you will see bubbles in the bleeder hose from air getting in from the bleeder threads or from a hose leak on the connection to the bleeder. Maybe my vacuum pressure was too high but it was a lesson learned and a container of brake fluid wasted. Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted March 22, 2021 I've rarely had any luck with my Mighty Vac. It could be operator error. Quote Share this post Link to post Share on other sites
Mach1 Driver 560 Report post Posted March 23, 2021 12 hours ago, RPM said: I've rarely had any luck with my Mighty Vac. It could be operator error. Bob, with your Motive bleeder, when you take the adapter off the master cylinder, wouldn't it be full to the top and tend to run over? I guess it would be best to have the export brace off and use a C clamp to rig the adapter to the master...do you have power brakes? Quote Share this post Link to post Share on other sites
aslanefe 333 Report post Posted March 23, 2021 12 hours ago, RPM said: I've rarely had any luck with my Mighty Vac. It could be operator error. 13 hours ago, TexasEd said: I've found you have to finish with a manual bleed because you will see bubbles in the bleeder hose from air getting in from the bleeder threads or from a hose leak on the connection to the bleeder. Maybe my vacuum pressure was too high but it was a lesson learned and a container of brake fluid wasted. I modified bleeder screws by soldering the side hole shut and drilling the straight hole all the way through. Put them on to side I am bleeding and connect the vacuum, this way there is no chance of sucking air through bleeder while vacuum bleeding. After bleeding one side, I replace the modified bleeder screw with a regular bleeder before I proceed to next corner. Quote Share this post Link to post Share on other sites
Mach1 Driver 560 Report post Posted March 25, 2021 On 3/22/2021 at 11:12 AM, RPM said: I've had good results starting with gravity bleed first, then final bleeding with a pressure bleed. Bob, with the Motive Power Bleeder there is an adapter that replaces the top cap of the master cylinder, then the pump on the bottle shown above is used to pressurize the system. When you're done and remove the adapter isn't the master filled to the top, and doesn't that spill when the adapter is removed? I would think its likely that the top of the master cylinder isn't level and that would cause a spill when the top is removed. What is your experience- is this messy and likely to put your paint at hazard? Just asking because I'd like to paint the master so it isn't a rusty boat anchor when done. Quote Share this post Link to post Share on other sites
aslanefe 333 Report post Posted March 26, 2021 12 hours ago, Mach1 Driver said: Bob, with the Motive Power Bleeder there is an adapter that replaces the top cap of the master cylinder, then the pump on the bottle shown above is used to pressurize the system. When you're done and remove the adapter isn't the master filled to the top, and doesn't that spill when the adapter is removed? I would think its likely that the top of the master cylinder isn't level and that would cause a spill when the top is removed. What is your experience- is this messy and likely to put your paint at hazard? Just asking because I'd like to paint the master so it isn't a rusty boat anchor when done. As far as I remember, the hose from the power bleeder sticks out a little bit from the adapter/cap. So when you remove the pressure from the bleeder, some fluid moves from master to bleeder and the fluid level in the master drops below the cap level which eliminates spill when adapter is removed from master. But if you remove the adapter while bleeder is still pressurized, you will make a mess. 1 Mach1 Driver reacted to this Quote Share this post Link to post Share on other sites
edwardthomson51@yahoo.com 1 Report post Posted March 29, 2021 thanks everyone....... i have heard lots of good things about the mighty vac so i will see what happens with that....but i may try gravity bleed first ....i will watch for the bubbles when pouring from the bottle........ thanks ed Quote Share this post Link to post Share on other sites
