I have a Mityvac for vacuum testing. I have tried it a couple times for brake bleed, but air leaking past the threads in the nipple made it marginal at best. How do you avoid this problem?
Gravity Brake Bleed
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I've done a gravity bleed on my 97 Voyager with no problems. You don't even need to jack it up or take the wheels off if you don't want to. You can get clear tubing at Home Depot by the foot. I think you want 1/4 in. ID but you might buy a few feet of one size larger and smaller to be sure. Get the big bottle of brake fluid and an empty jar or bottle (jar is less likely to tip over). Open reservoir cap, put hose on bleeder, and open bleeder. The fluid will flow pretty slowly but its not so bad. When you see clean fluid, close the bleeder and move to the next wheel. It will seem slow if you are just sitting there staring at the hose so have another project going on at the same time (clean interior, oil change etc.) just be sure to keep the res topped off.
Yeah, I had all sorts of problems with the mityvac. Wont seal to the bleeder. Falls off the bleeder all the time. Just messy junk. Ive got a power bleeder now. Going to use that this weekend.
Originally Posted By: G.Frost
I have a Mityvac for vacuum testing. I have tried it a couple times for brake bleed, but air leaking past the threads in the nipple made it marginal at best. How do you avoid this problem?
Remove the bleeder valve and tightly wrap(stretch it thin) a couple rounds of Teflon tape on the threads, that will stop most of the air leak... Also helps to keep vac fairly low(about 6-8") higher vac will probably suck past the tape...
I have a Mityvac for vacuum testing. I have tried it a couple times for brake bleed, but air leaking past the threads in the nipple made it marginal at best. How do you avoid this problem?
Remove the bleeder valve and tightly wrap(stretch it thin) a couple rounds of Teflon tape on the threads, that will stop most of the air leak... Also helps to keep vac fairly low(about 6-8") higher vac will probably suck past the tape...
Originally Posted By: JamesBond
I've done a gravity bleed on my 97 Voyager with no problems. You don't even need to jack it up or take the wheels off if you don't want to. You can get clear tubing at Home Depot by the foot. I think you want 1/4 in. ID but you might buy a few feet of one size larger and smaller to be sure. Get the big bottle of brake fluid and an empty jar or bottle (jar is less likely to tip over). Open reservoir cap, put hose on bleeder, and open bleeder. The fluid will flow pretty slowly but its not so bad. When you see clean fluid, close the bleeder and move to the next wheel. It will seem slow if you are just sitting there staring at the hose so have another project going on at the same time (clean interior, oil change etc.) just be sure to keep the res topped off.
Good to know.
I did the passenger side doing the two person method. For the driver's side I couldn't get one lug nut off, even with my electric impact wrench. So, I'm going to take it to a shop near by and have them get that nut off and replace it with another. Then, I will bleed the driver's side this friday night.
I've done a gravity bleed on my 97 Voyager with no problems. You don't even need to jack it up or take the wheels off if you don't want to. You can get clear tubing at Home Depot by the foot. I think you want 1/4 in. ID but you might buy a few feet of one size larger and smaller to be sure. Get the big bottle of brake fluid and an empty jar or bottle (jar is less likely to tip over). Open reservoir cap, put hose on bleeder, and open bleeder. The fluid will flow pretty slowly but its not so bad. When you see clean fluid, close the bleeder and move to the next wheel. It will seem slow if you are just sitting there staring at the hose so have another project going on at the same time (clean interior, oil change etc.) just be sure to keep the res topped off.
Good to know.
I did the passenger side doing the two person method. For the driver's side I couldn't get one lug nut off, even with my electric impact wrench. So, I'm going to take it to a shop near by and have them get that nut off and replace it with another. Then, I will bleed the driver's side this friday night.
Originally Posted By: G.Frost
I have a Mityvac for vacuum testing. I have tried it a couple times for brake bleed, but air leaking past the threads in the nipple made it marginal at best. How do you avoid this problem?
Air leaking passes the threads in the nipple doesn't go back in to the brake line, brake fluid and some air are sucked into the Mityvac container so it should not be a problem.
Originally Posted By: Colt45ws
Yeah, I had all sorts of problems with the mityvac. Wont seal to the bleeder. Falls off the bleeder all the time. Just messy junk. Ive got a power bleeder now. Going to use that this weekend.
Did you used the long rigid hose comes with the Mityvac ? You should buy a couple feet of thick but flexible hose from Home Depot or Lowe's or a hardware store, the hose should be similar with the one comes with Motive Power Bleeder. Then there will be no more falling off the bleeder screw.
I used both Motive Power Bleeder and Mityvac 7201 on my cars, Mityvac is much easier, cleaner, faster ... to use than Motive. I was so satisfy with Mityvac 7201 I sold Motive.
The key for successful vacuum bleeding is don't pump the Mityvac more than 5-6 pumps, you don't want a weak vacuum but not too strong either.
I have a Mityvac for vacuum testing. I have tried it a couple times for brake bleed, but air leaking past the threads in the nipple made it marginal at best. How do you avoid this problem?
Air leaking passes the threads in the nipple doesn't go back in to the brake line, brake fluid and some air are sucked into the Mityvac container so it should not be a problem.
Originally Posted By: Colt45ws
Yeah, I had all sorts of problems with the mityvac. Wont seal to the bleeder. Falls off the bleeder all the time. Just messy junk. Ive got a power bleeder now. Going to use that this weekend.
Did you used the long rigid hose comes with the Mityvac ? You should buy a couple feet of thick but flexible hose from Home Depot or Lowe's or a hardware store, the hose should be similar with the one comes with Motive Power Bleeder. Then there will be no more falling off the bleeder screw.
I used both Motive Power Bleeder and Mityvac 7201 on my cars, Mityvac is much easier, cleaner, faster ... to use than Motive. I was so satisfy with Mityvac 7201 I sold Motive.
The key for successful vacuum bleeding is don't pump the Mityvac more than 5-6 pumps, you don't want a weak vacuum but not too strong either.
The weak vacuum(1 or 2 pumps) may not suck all the air leak from the threads in the nipple into the container and the bleeding rate is too slow, too strong vacuum may dislodge the hose from the nipple. From my experience bleeding brake fluid in 4 cars, I found that 4-5 pumps is the best compromise, it suck brake fluid at good pace and no air leak from the threads in the nipple getting back into brake system.
The least vacuum is best. As long as you get flow, you're OK.
Strong vacuum may spike and draw air around the wheel cylinder seals.
If the threads ever leak during vacuum bleeding it is of ZERO consequence.
Strong vacuum may spike and draw air around the wheel cylinder seals.
If the threads ever leak during vacuum bleeding it is of ZERO consequence.
The only consequence I had from air leaking past the threads is just pumping lots of air and very little brake fluid. I tried the Mityvak on an 05 civic and 88 Accord both with the same result; mostly air, very little brake fluid.
I fiddled a bit trying to tighten or loosed the nipple to minimize the air leaking. I didn't try putting teflon tape on the nipple threads though... (ended up using the peddle to pump it out.)
I fiddled a bit trying to tighten or loosed the nipple to minimize the air leaking. I didn't try putting teflon tape on the nipple threads though... (ended up using the peddle to pump it out.)
see my PM
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Originally Posted By: G.Frost
A word of warning if you are using the 'peddle pumping' method; do not push the peddle to the floor, only push as far as normal travel.
Particularly in an older car, you will swipe crud into the master seals and soon after be replacing/rebuilding the master cylinder.
That's why an alternative, reliable one-person method is so desireable; inevitably the helper turns out to be one's wife, girlfriend, kid or neighbor and they ALWAYS wind up with the pedal all the way to the floor, no matter how many times you tell them not to do it.
A word of warning if you are using the 'peddle pumping' method; do not push the peddle to the floor, only push as far as normal travel.
Particularly in an older car, you will swipe crud into the master seals and soon after be replacing/rebuilding the master cylinder.
That's why an alternative, reliable one-person method is so desireable; inevitably the helper turns out to be one's wife, girlfriend, kid or neighbor and they ALWAYS wind up with the pedal all the way to the floor, no matter how many times you tell them not to do it.
Originally Posted By: HTSS_TR
Originally Posted By: Colt45ws
Yeah, I had all sorts of problems with the mityvac. Wont seal to the bleeder. Falls off the bleeder all the time. Just messy junk. Ive got a power bleeder now. Going to use that this weekend.
Did you used the long rigid hose comes with the Mityvac ? You should buy a couple feet of thick but flexible hose from Home Depot or Lowe's or a hardware store, the hose should be similar with the one comes with Motive Power Bleeder. Then there will be no more falling off the bleeder screw.
I used both Motive Power Bleeder and Mityvac 7201 on my cars, Mityvac is much easier, cleaner, faster ... to use than Motive. I was so satisfy with Mityvac 7201 I sold Motive.
The key for successful vacuum bleeding is don't pump the Mityvac more than 5-6 pumps, you don't want a weak vacuum but not too strong either.
I ended up doing a sort of hybrid flush with the Motive.
I attached the Motive and pumped it up for a leak test.
While I had it pumped up I opened the bleeder screw on the master cylinder and drained that out a bit.
No leaks on the setup so I opened the Motive to fill and there were all sorts of black flakes inside!
I didnt have anything to clean it out with, so I just topped off the reservoir and just used the Motive to apply pressure.
I used a Mityvac container with a short piece of hose to attach to the bleeder. That way I could measure what I was taking out.
I found 170-180ml was safe between top offs of the reservoir. So that is what I took out of each wheel cylinder.
I think Im probably just going to use it that way. Then I dont have to worry about cleaning it out.
Originally Posted By: Colt45ws
Yeah, I had all sorts of problems with the mityvac. Wont seal to the bleeder. Falls off the bleeder all the time. Just messy junk. Ive got a power bleeder now. Going to use that this weekend.
Did you used the long rigid hose comes with the Mityvac ? You should buy a couple feet of thick but flexible hose from Home Depot or Lowe's or a hardware store, the hose should be similar with the one comes with Motive Power Bleeder. Then there will be no more falling off the bleeder screw.
I used both Motive Power Bleeder and Mityvac 7201 on my cars, Mityvac is much easier, cleaner, faster ... to use than Motive. I was so satisfy with Mityvac 7201 I sold Motive.
The key for successful vacuum bleeding is don't pump the Mityvac more than 5-6 pumps, you don't want a weak vacuum but not too strong either.
I ended up doing a sort of hybrid flush with the Motive.
I attached the Motive and pumped it up for a leak test.
While I had it pumped up I opened the bleeder screw on the master cylinder and drained that out a bit.
No leaks on the setup so I opened the Motive to fill and there were all sorts of black flakes inside!
I didnt have anything to clean it out with, so I just topped off the reservoir and just used the Motive to apply pressure.
I used a Mityvac container with a short piece of hose to attach to the bleeder. That way I could measure what I was taking out.
I found 170-180ml was safe between top offs of the reservoir. So that is what I took out of each wheel cylinder.
I think Im probably just going to use it that way. Then I dont have to worry about cleaning it out.
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Well even after bleeding the brakes, they suck [censored]. So, i decided to get the car up on a lift at my uncle's shop. And, noticed the rear brake lines are rusted up and exploded. There is brake fluid all over the underside near the gas tank. So, I'm in the process of changing the brake lines for the rear. No wonder, the brakes suck.
Originally Posted By: css9450
Originally Posted By: G.Frost
A word of warning if you are using the 'peddle pumping' method; do not push the peddle to the floor, only push as far as normal travel.
Particularly in an older car, you will swipe crud into the master seals and soon after be replacing/rebuilding the master cylinder.
That's why an alternative, reliable one-person method is so desireable; inevitably the helper turns out to be one's wife, girlfriend, kid or neighbor and they ALWAYS wind up with the pedal all the way to the floor, no matter how many times you tell them not to do it.
Put a piece of 2x4 under the pedal and they won't push it to the floor.
Originally Posted By: G.Frost
A word of warning if you are using the 'peddle pumping' method; do not push the peddle to the floor, only push as far as normal travel.
Particularly in an older car, you will swipe crud into the master seals and soon after be replacing/rebuilding the master cylinder.
That's why an alternative, reliable one-person method is so desireable; inevitably the helper turns out to be one's wife, girlfriend, kid or neighbor and they ALWAYS wind up with the pedal all the way to the floor, no matter how many times you tell them not to do it.
Put a piece of 2x4 under the pedal and they won't push it to the floor.
Originally Posted By: hypervish
Well even after bleeding the brakes, they suck [censored]. So, i decided to get the car up on a lift at my uncle's shop. And, noticed the rear brake lines are rusted up and exploded. There is brake fluid all over the underside near the gas tank. So, I'm in the process of changing the brake lines for the rear. No wonder, the brakes suck.
While you're under there fixing lines, take a good look for any other rusted out lines. The hoses at the front might be worth replacing even if they look good considering how often they fail. Either front hose can develop an aneurysm which will give a low pedal and for some reason the left front has a habit of collapsing. A left front brake hose turning into a check valve is pretty much a Dodge thing. Regardless of whether you need to do any repairs beyond the one line it's good practice to stand hard on the brake for a couple of seconds with the engine running once or twice after the bleed. Anything weak enough to blow out on the road will blow out when you're safely stopped instead.
Well even after bleeding the brakes, they suck [censored]. So, i decided to get the car up on a lift at my uncle's shop. And, noticed the rear brake lines are rusted up and exploded. There is brake fluid all over the underside near the gas tank. So, I'm in the process of changing the brake lines for the rear. No wonder, the brakes suck.
While you're under there fixing lines, take a good look for any other rusted out lines. The hoses at the front might be worth replacing even if they look good considering how often they fail. Either front hose can develop an aneurysm which will give a low pedal and for some reason the left front has a habit of collapsing. A left front brake hose turning into a check valve is pretty much a Dodge thing. Regardless of whether you need to do any repairs beyond the one line it's good practice to stand hard on the brake for a couple of seconds with the engine running once or twice after the bleed. Anything weak enough to blow out on the road will blow out when you're safely stopped instead.
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