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Harbor freight brake bleeder

red1100

Forum Mentor
Anyone use this unit? I'm trying it on a Cavalcade front caliper set and just cant seem to get all the air out. Run a bunch of fluid through it and lever better but not what it should be.
 
Used mine just the other day. They dont last forever but arent expensive to replace either
 
I have one and it works fine, more sturdy and cheaper than Mityvac. I use little zip ties on the hose over the bleed nipple to keep it firmly in place and put some grease on the threads so I don't get false reading of air bubbles coming through. Then I pump up and have a helper keep the fluid topped up, and slightly pull the brake in a bit. I can bleed the GS twin front brakes quick and easy, but the CB750 single caliper is near impossible to get the air out, and it's very frustrating. I had the same issues years ago on my first CB750. Some brakes just don't seem to want to cooperate.
 
Years ago I swapped the the fork legs side to side on my 74 GT 750 to reduce swinging inertia forward of the triple yoke centerline.Putting the calipers closer to the triples centerline makes swinging the bars back and forth easier. But I couldn't get the air out of the calipers. After a while I realized swapping calipers side to side put the bleeders below the top of the caliper piston which made it impossible to bleed. Had to take the caliper off the leg, set it on the rotor at the top and then bleed. It worked.
 
I have the brass HF vacuum pump and it's fantastic. The plastic Mityvac is expensive and complete garbage.

Wrap the gauge in a few layers of clear tape before using it; you're going to drop it at some point, and that stupid gauge is extremely brittle.


Couple of things if you're having trouble bleeding:

1) Air always gets in via the threads around the bleeder. I generally wrap the threads on the bleeder with a few turns of teflon pipe tape to stop this. If you're reasonably neat, there's no danger of teflon bits getting into the system (and even if they do, they're certainly not going to hurt anything in the caliper). Some use grease, but I'd rather not risk contaminating my brake fluid with grease.

2) You have to "bench bleed" the master cylinder if it's been emptied. Pumping with the lever and pulling fluid through with a vacuum pump won't get this air out. If it's already mounted on the bars, remove the lever, find something non-damaging to push with (a wooden dowel, a but driver, a screwdriver wrapped in tape, etc.) and then slowly push the piston alllllllll the way in and back several times. You'll burp those last few bubbles out of that weensy bypass hole at the bottom. If you push too fast, you'll get a jet of brake fluid in the chops.

3) Once you have all the air out, sometimes you have issues with the seals retracting the pads a little too much, so you need more than one pump, or the lever is at the bar before the pads contact the disk. Two common causes of this are crappy aftermarket rebuild kits (the imitation seals in these are dangerous junk; buy OEM only). and crud left in the seal groove. You have to get in there with your best eyeglasses and a sharp pointy tool and get every last bit of gunk out of the corners.
 
A trick some folks use is to fully pull the lever in wrap it or tie it to the bars, turn the bars all the way to the left so the MC is at its' highest point and leave it overnight. The trapped air gradually works its' way out. I have used this procedure on my Honda wings and it worked for me.
 
I have the HF bleeder that you hook to an air compressor. It is fan-freaking-tactic. It's basically the same thing that
Motion Pro sells for $100. HF costs around $30. Ill never go back to manual bleeders

Mad
 
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When I was rehabbing my 450 a few years back i came across the "reverse bleeding method" where instead of filling the system with fluid from the master cylinder down you pump it full from the bleeder upward. It worked quite well on the single disk setup and has also been used with success on my dual disk Goldwing. For about $2 worth of parts you can make your own and can't beat it!

s-l1600.jpg
 
Brake Bleeder

Brake Bleeder

I don't believe this is a HF special...borrowed it from a friend.

IMG_5861_zps287616a6.jpg


IMG_5862_zps1c6e7c69.jpg


IMG_5863_zps050cea0f.jpg


I'll ask him what brand it is...it worked great!

Ed
 
It’s a MityVac. Apparently sold at HF for $44, not a knockoff.

Ed

****
 
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That's how I do it on my mountain bikes, I think I'll try it on my Honda.

When I was rehabbing my 450 a few years back i came across the "reverse bleeding method" where instead of filling the system with fluid from the master cylinder down you pump it full from the bleeder upward. It worked quite well on the single disk setup and has also been used with success on my dual disk Goldwing. For about $2 worth of parts you can make your own and can't beat it!

View attachment 62512
 
I don't believe this is a HF special...borrowed it from a friend.


I'll ask him what brand it is...it worked great!

Ed

Well, um, it says Mityvac right there on the gauge...

Long-term, that plastic Mityvac pump is garbage. For one, the plastic is vulnerable to brake fluid; you know, the stuff you're working with... no, brake fluid shouldn't contact the pump, but stuff happens. For another, the seals inside that pump are junk and wear out quickly.

The cheap brass-bodied pump from HF lasts a lot longer. In fact, Harbor Freight does sell that exact crappy plastic Mityvac pump for $45, right next to their superior brass version for $25. They also sell a higher-end "Maddox" brass pump. I don't know anything about that.


None of them will tolerate brake fluid or dirt in the seals; I usually install a large clear plastic fuel filter between the pump and the fluid cup to act as a reservoir, keep dirt out (dirt's usually not a problem with brake systems, but it can be an issue with testing vacuum actuators and such), and to give me a little extra warning if fluid is starting to get slurped into the pump, like if the cup tips over. As it usually does...


That pneumatic brake bleeding kit from HF looks very interesting too and the reviews are great -- I'll probably pick one up next time I'm doing brake stuff.
https://www.harborfreight.com/brake-fluid-bleeder-92924.html


I've never been impressed with reverse bleeding compared to vacuum bleeding. But do whatever you're comfortable with, I guess.

One very important distinction is that reverse bleeding should ONLY be done with a new or newly rebuilt system. NEVER reverse bleed to do a flush on a system that's been in use very long; otherwise you're sending whatever is happening in the calipers up to the far more sensitive master cylinder.

On most (but not all) newer ABS bikes (check the manual), conventional bleeding works fine for flushing, but folks have had issues trying reverse bleeding on systems that haven't been flushed recently; even very mild gunk from the calipers can play havoc with ABS components, and sometimes there are check valves and whatnot that don't take kindly to or allow reverse flow.
 
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Well, um, it says Mityvac right there on the gauge...

Long-term, that plastic Mityvac pump is garbage. For one, the plastic is vulnerable to brake fluid; you know, the stuff you're working with... no, brake fluid shouldn't contact the pump, but stuff happens. For another, the seals inside that pump are junk and wear out quickly.

The cheap brass-bodied pump from HF lasts a lot longer. In fact, Harbor Freight does sell that exact crappy plastic Mityvac pump for $45, right next to their superior brass version for $25. They also sell a higher-end "Maddox" brass pump. I don't know anything about that.


None of them will tolerate brake fluid or dirt in the seals; I usually install a large clear plastic fuel filter between the pump and the fluid cup to act as a reservoir, keep dirt out (dirt's usually not a problem with brake systems, but it can be an issue with testing vacuum actuators and such), and to give me a little extra warning if fluid is starting to get slurped into the pump, like if the cup tips over. As it usually does...


That pneumatic brake bleeding kit from HF looks very interesting too and the reviews are great -- I'll probably pick one up next time I'm doing brake stuff.
https://www.harborfreight.com/brake-fluid-bleeder-92924.html


I've never been impressed with reverse bleeding compared to vacuum bleeding. But do whatever you're comfortable with, I guess.

One very important distinction is that reverse bleeding should ONLY be done with a new or newly rebuilt system. NEVER reverse bleed to do a flush on a system that's been in use very long; otherwise you're sending whatever is happening in the calipers up to the far more sensitive master cylinder.

On most (but not all) newer ABS bikes (check the manual), conventional bleeding works fine for flushing, but folks have had issues trying reverse bleeding on systems that haven't been flushed recently; even very mild gunk from the calipers can play havoc with ABS components, and sometimes there are check valves and whatnot that don't take kindly to or allow reverse flow.

That pneumatic bleeder is what I have. It's outstanding.

Mad
 
Well, um, it says Mityvac right there on the gauge...

Long-term, that plastic Mityvac pump is garbage. For one, the plastic is vulnerable to brake fluid; you know, the stuff you're working with... no, brake fluid shouldn't contact the pump, but stuff happens. For another, the seals inside that pump are junk and wear out quickly.

The cheap brass-bodied pump from HF lasts a lot longer. In fact, Harbor Freight does sell that exact crappy plastic Mityvac pump for $45, right next to their superior brass version for $25. They also sell a higher-end "Maddox" brass pump. I don't know anything about that.


None of them will tolerate brake fluid or dirt in the seals; I usually install a large clear plastic fuel filter between the pump and the fluid cup to act as a reservoir, keep dirt out (dirt's usually not a problem with brake systems, but it can be an issue with testing vacuum actuators and such), and to give me a little extra warning if fluid is starting to get slurped into the pump, like if the cup tips over. As it usually does...


That pneumatic brake bleeding kit from HF looks very interesting too and the reviews are great -- I'll probably pick one up next time I'm doing brake stuff.
https://www.harborfreight.com/brake-fluid-bleeder-92924.html


I've never been impressed with reverse bleeding compared to vacuum bleeding. But do whatever you're comfortable with, I guess.

One very important distinction is that reverse bleeding should ONLY be done with a new or newly rebuilt system. NEVER reverse bleed to do a flush on a system that's been in use very long; otherwise you're sending whatever is happening in the calipers up to the far more sensitive master cylinder.

On most (but not all) newer ABS bikes (check the manual), conventional bleeding works fine for flushing, but folks have had issues trying reverse bleeding on systems that haven't been flushed recently; even very mild gunk from the calipers can play havoc with ABS components, and sometimes there are check valves and whatnot that don't take kindly to or allow reverse flow.

Ahhh, heck, I don't remember the name brand of it...even though it was marked on the white gauge, I couldn't make it out.

I've only ever used one of those once so the name had escaped me.

The guy I borrowed it from is a Boeing Engineer who helped me do the valve clearance as well.

The info you provided is a good advice and should help anyone taking on this task.

Ed

****
 
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I think I'll get one of those Pneumatic bleeders too.. Wonder how much CFM you need on your compressor for it to work well.

I think a bonus with those things is that if you can get continuous flow you should be able to flush without needing to trigger the ABS pump. Some newer bikes & cars need you to trigger the pump in order to bleed it through otherwise....
 
You don't need a ton of air pressure to do the bleeding. But you have to really watch the fluid level in the reservoir. It goes down FAST !

Mad
 
The metal one. Plastic handles break easy. Neithets gonna last forever and be sure you don't lay it down in a manner fluid can get into the hose from the canister to the pump
Fluid raises holly hellll on the pump oring.
 
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