Motive bleeder question
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
Motive bleeder question
I bought one because many here seemed to love it.
Just finished replacing all lines and MC and tried the Motive pressure bleed out. What am I missing? It hooked up fine (the board and c-clamp version I read about here) and held pressure but nothing came out. I hooked up my old vacuum pump to the bleeder screws and out came the air and fluid. The pressure Gage on the motive dropped as it came out but only with vacuum on the bleeder. I tried more pressure, but still nothing without vacuum.
I thought you just pumped it up and opened the bleeder. What did I miss?
Just finished replacing all lines and MC and tried the Motive pressure bleed out. What am I missing? It hooked up fine (the board and c-clamp version I read about here) and held pressure but nothing came out. I hooked up my old vacuum pump to the bleeder screws and out came the air and fluid. The pressure Gage on the motive dropped as it came out but only with vacuum on the bleeder. I tried more pressure, but still nothing without vacuum.
I thought you just pumped it up and opened the bleeder. What did I miss?
Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
I have the cheapest pressure bleeder that works...I just drilled a hole in an an old master cyl cap, put an air fitting in it, attach the air hose, turn the pressure to 5 lbs and I'm in business, just have to be careful not to run the cyl dry.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
About the only thing that will prevent fluid from passing thru the MC is if the MC rod is not in the fully retracted position. Either out of adjustment, not seated correctly or too long a rod. Operate the MC, looking into it and make sure the piston cups retract fully past the little fill holes at the bottom.
Other than that, a porportioning valve will block fluid to either the front or rear system, but not both.
Lastly the flex hoses at all wheels can be collapsed, but that is not likely.
It does take a lot of fluid to fill any empty system.
You can flush with up to 80 psi, but bleed with the minimum pressure that pushes fluid.
Other than that, a porportioning valve will block fluid to either the front or rear system, but not both.
Lastly the flex hoses at all wheels can be collapsed, but that is not likely.
It does take a lot of fluid to fill any empty system.
You can flush with up to 80 psi, but bleed with the minimum pressure that pushes fluid.
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
All New
The booster, master cylinder, all metal lines, flex lines, bleeder screws and front calipers are all new. The vacuum pump pulled the fluid fine but the pressure from the motive seemed to do nothing. It did drop as I 'pulled' fluid but it 'pushed' nothing.
I don't remember the exact pressure readings on the motive but I tried it at 25%, 50% and 75% of what the dial showed.
The booster came with two rods, a short one in the booster and a longer one in a separate package. The longer one was way to long so I left the shorter one in place.
I don't remember the exact pressure readings on the motive but I tried it at 25%, 50% and 75% of what the dial showed.
The booster came with two rods, a short one in the booster and a longer one in a separate package. The longer one was way to long so I left the shorter one in place.
Last edited by dburgjohn; Mar 20, 2009 at 10:41 AM. Reason: add info
Limping across the line
Joined: Oct 2002
Posts: 5,299
Likes: 109
From: Peoria Az
dumb question but your Motive bleeder has fluid in it?
I went to Lowes depot and picked up a 6ft length of vynil tubing and use that between the Bleeder and MC.
Can you see fluid moving from the Motive bleeder to the MC?
DId you bench bleed the MC?
I went to Lowes depot and picked up a 6ft length of vynil tubing and use that between the Bleeder and MC.
Can you see fluid moving from the Motive bleeder to the MC?
DId you bench bleed the MC?
Pro
Joined: Apr 2006
Posts: 625
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From: Southern California
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Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
dry tank
no fluid in tank, only fluid in MC. I know it pumped up because I heard it leaking first time before I snugged down the C-clamp. Plus as I bleed it with vacuum I could see the pressure gage drop. It did not drop during my supper break. what gives?
MC was bench bleed was was done prior to install. The bleed is going as expected for a vacuum only bleed. The motive seems to be doing nothing. I just don't know why.
MC was bench bleed was was done prior to install. The bleed is going as expected for a vacuum only bleed. The motive seems to be doing nothing. I just don't know why.
Last edited by dburgjohn; Mar 21, 2009 at 12:23 AM. Reason: addl info
Pro
Joined: Feb 2005
Posts: 627
Likes: 5
From: Frisco TX
I'd try attacking this like you would an air leak in one of your vacuum hoses (ie - headlights). Start unhooking things to identify the culprit. Maybe start with the hard lines that connect to the master cylinder. If under pressure the fluid flows coming out of the master cylinder then you know the MC is good. Then re-hook up the lines to the MC and unhook after the proportioning valve. So on a so forth. It'll be a little messy but it should be effective. I'll bet you it's your proportioning valve. Good luck.
Racer
Joined: Feb 2009
Posts: 343
Likes: 0
From: San Diego CA
I'd try attacking this like you would an air leak in one of your vacuum hoses (ie - headlights). Start unhooking things to identify the culprit. Maybe start with the hard lines that connect to the master cylinder. If under pressure the fluid flows coming out of the master cylinder then you know the MC is good. Then re-hook up the lines to the MC and unhook after the proportioning valve. So on a so forth. It'll be a little messy but it should be effective. I'll bet you it's your proportioning valve. Good luck.
- Be positive to bench bleed properly
- make sure the brake pedal is returning to top
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
but if there was a blockage no fluid would have come out at the wheels. I got air then fluid using the vacuum pump. If there was a blockage I could understand not fluid movement but there was, just pulled not pushed.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
How are you connecting the Motive to the MC cover? If you are using a snap coupling, make sure the male and female are matching configurations. There are some combination's that will snap together, but the "shutoff" in the actual snap coupling does not release.
If it was the proportioning/differential valve, you should still get fluid out of one end of the vehicle.
If it was the proportioning/differential valve, you should still get fluid out of one end of the vehicle.
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
proportioning valve
I did pull the valve when I removed the old lines. I unscrewed the valve by accident because when I put the line wrench on, it came off rather than the line fitting removing from the valve. I put it back, cleaned it up and blew it out with air hose.
could I have damaged it in some way?
how do you test?
tried to bleed more today, pedal drops to the floor with nothing. Some fluid comes out of some bleeder screws.
what did I do to drive myself crazy before I got bit by Corvette bug?
could I have damaged it in some way?
how do you test?
tried to bleed more today, pedal drops to the floor with nothing. Some fluid comes out of some bleeder screws.
what did I do to drive myself crazy before I got bit by Corvette bug?
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
from what I read
looking at this and other forums I wonder if my use of the air hose could have blasted the piston in the valve and jammed it to one side?
Or the fact that when I tried to remove the line to the rear, the valve unscrewed into two parts. It did not seem damaged so I put it back together. The old rear line fitting was frozen to it and had to cut line and remove fitting after valve removed from car.
Or the fact that when I tried to remove the line to the rear, the valve unscrewed into two parts. It did not seem damaged so I put it back together. The old rear line fitting was frozen to it and had to cut line and remove fitting after valve removed from car.
Last edited by dburgjohn; Mar 23, 2009 at 03:41 PM. Reason: add info
