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| − | I have tried pressure power bleeders and they can be quite a mess. Brake fluid hurts very bad when you get it in your eyes and will take paint off. Having it pressurized isn't my idea of a fun time. Having brake fluid under vacuum is much more idiot proof.
| + | ==Overview== |
| | + | These instructions will allow a person to successfully vacuum bleed a hydraulic brake or clutch system. |
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| − | What you need: | + | ==What is needed:== |
| − | -Vacuum pump
| + | *Vacuum pump |
| − | -Glass jar with lid
| + | *Glass jar with lid |
| − | -Clear tubing
| + | *Clear tubing |
| − | -Brass fittings
| + | *Brass fittings |
| − | -All this should cost around $20
| + | *All this should cost around $20 |
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| − | ==Vacuum Pump== | + | ==Vacuum jar== |
| | + | Most any jar can be used; the one shown is an old spaghetti sauce jar with drilled holes in the lid and some brass fittings in it. Use rubber washers to get a tight seal. Using a canning jar like made by Ball or Mason will work well; they have a lid insert with a rubber seal. |
| | + | *[http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0490a.jpg Jar and lid with fittings] |
| | + | *[http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0492a.jpg Underside of jar lid with fittings] |
| | + | *[http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0494a.jpg Pneumatic vacuum pump] |
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| − | You can get inexpensive venturi (need an air compressor to operate) vacuum pumps made for AC work from Harbor Freight. The one I have is just like the first link but is red and had a R12 fitting on it. The vacuum fitting is 1/8-NPT on the other side.
| + | ==Fittings== |
| | + | Shown being used are 3 male 1/4-NPT x 1/8 barb fittings, 1 female 1/4-NPT x 1/8 barb fitting, 1 female 1/4-NPT x 1/8-NPT coupler, and 1 female 1/4-NPT 90° fitting. Also put a ball valve on the pressure input side. The valve is needed to control the vacuum. |
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| − | [http://www.harborfreight.com/air-vacuum-pump-with-r134a-and-r12-connectors-96677.html Harbor Freight vacuum pump]
| + | ==Vacuum pump== |
| | + | There are several brands of hand held vacuum pumps available. The most recognised is probably the Miti-Vac unit. |
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| − | ==Glass Jar==
| + | You can also get inexpensive venturi (need an air compressor to operate) vacuum pumps made for AC work from Harbor Freight. The vacuum fitting is 1/8-NPT on the other side. |
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| − | I used an old spaghetti sauce jar, drilled some holes in the lid and put some brass fittings in it. I needed to use washers to get a tight seal.
| + | {| |
| | + | |[[File:Miti vac kit.jpg|thumb|center|400px|Miti-Vac bleeder kit p/n MV8500]] |
| | + | |[[File:Hf air vac pump.jpg|thumb|center|400px|Pneumatic Venturi type vacuum pump similar to what's sold by [http://www.harborfreight.com/air-vacuum-pump-with-r134a-and-r12-connectors-96677.html Harbor Freight]]] |
| | + | |} |
| | | | |
| | + | ==Warnings== |
| | + | There are a few issues with vacuum bleeding. First is sucking air around the bleeder valve threads. The solution is to use Teflon (PTFE) tape or Teflon thread sealer on the threads. If some air leaks past the threads this isn't much of an issue as long as mostly brake fluid is in the bleeder hose. Throttling down the vacuum pump also helps. |
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| − | [http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0490a.jpg Jar and lid with fittings]
| + | Be sure to keep an eye on the fluid level in the master cylinder reservoir as it will go down quickly. If you are flushing out old brake fluid use a turkey baster (that will never be used on food again) to remove the old brake fluid from the reservoir. Refill with fresh fluid before resuming bleeding. |
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| | + | {{Warning|Most brake fluid will severely damage painted surfaces if exposed for long. Remove and wash using a lot of clean water and mild soap, rinse clean.}} |
| | + | {{Warning|If you are using engine vacuum for bleeding the brakes, then this means the engine is running . Anytime the engine is running unattended by a driver, chock the wheels, put the transmission in Park and/or set the parking brake. Good ventilation is essential!}} |
| | + | {{Warning|Be safe: If the vehicle is raised off the ground, use jackstands and chock the wheels, use Park and parking brake as needed.}} |
| | + | {{Warning|The only thing (chemical) that should ever make contact with brake fluid is the same type of brake fluid.}} |
| | + | Also see [[Health and safety in the shop or garage]]. |
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| − | [http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0492a.jpg]Underside of jar lid with fittings]
| + | ==How to use the venturi-type vacuum pump== |
| | + | Hook up a hose from the brake bleeder to the fitting on the jar with the short piece of hose inside the jar. Hook the other fitting on the jar to the vacuum pump. Hook up the vacuum pump to your compressor. A ball valve can be used on the compressor side to throttle down the amount of vacuum. |
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| | + | ==Using a hand held vacuum pump== |
| | + | Leave the engine bay alone, go to an auto parts store and buy a hand-operated vacuum pump that includes all the fittings needed to bleed a hydraulic system, or from Amazon.com, etc.: Cost is about $30 made of plastic resin, $35 for the brass version, ca. 2012. |
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| − | [http://s36.photobucket.com/albums/e24/Triaged/Misc/?action=view¤t=IMG_0494a.jpg Jar assembled ready for vacuum bleeding]
| + | Regardless of the type of vacuum source used, remember to vent the master cylinder by loosening the cover. If you leave the lid locked down when you are trying to bleed, the fluid won't flow. |
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| − | ==Fittings== | + | ==Using a syringe== |
| | + | A large syringe (30–100cc) can be used to draw out the fluid. These syringes do not have needles and are disposable. |
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| − | I used 3 male 1/4-NPT x 1/8 barb fittings, 1 female 1/4-NPT x 1/8 barb fitting, 1 female 1/4-NPT x 1/8-NPT coupler, and 1 female 1/4-NPT 90° fitting. I also put a ball valve on the pressure input side. The valve is needed to control the vacuum.
| + | ===Alternative vacuum source=== |
| | + | This might not be 'recommended' by the auto manufacturers, but engine vacuum has been successfully used instead of a pump. No compressor or pump is required, just the jar and some hoses. If using the engine as a vacuum source, do make sure you are using '''manifold''' vacuum at the sourcing port and not ported vacuum. |
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| − | ==Note==
| + | Make sure to connect directly to intake manifold vacuum (below carburetor or throttle body), do NOT go through any valves,solenoids, etc. that may be damaged if brake fluid enters them (although the jar should prevent that). |
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| − | This might not be 'recommended' by the auto manufacturers, but I have successfully used engine vacuum instead of a pump. No compressor or pump is required, just the jar and some hoses.
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| − | Make sure to connect directly to intake manifold vacuum (below carburetor or throttle body), do NOT go through any valves,solenoids, etc. that may be damaged if brake fluid enters them (although the jar should prevent that.) | + | |
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| | If you do get brake fluid past the jar and into the engine, a little bit won't hurt, just STAY AWAY from the exhaust pipe! Burning brake fluid STINKS!!! | | If you do get brake fluid past the jar and into the engine, a little bit won't hurt, just STAY AWAY from the exhaust pipe! Burning brake fluid STINKS!!! |
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| − | Not recommended for Diesels, because they have a vacuum pump, normally with a rubber diaphragm. Brake fluid could damage it. | + | Not recommended for diesels because they have a vacuum pump, normally with a rubber diaphragm. Brake fluid could damage it. |
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| − | ==Use==
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| − | Hook up a hose from the brake bleeder to the fitting on the jar with the short piece of hose inside the jar. Hook the other fitting on the jar to the vacuum pump. Hook up the vacuum pump to your compressor. I used a ball valve on the compressor side to throttle down the amount of vacuum.
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| − | There are a few issues with vacuum bleeding. First is sucking air around the bleeder valve threads. The solution is to use Teflon (PTFE) tape or Teflon thread sealer on the threads. If some air leaks past the threads this isn't much of an issue as long as mostly brake fluid is in the bleeder hose. Throttling down the vacuum pump also helps.
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| − | Be sure to keep an eye on the fluid level in the master cylinder reservoir as it will go down quickly. If you are flushing out old brake fluid use a turkey baster (that will never be used on food again) to remove the old brake fluid from the reservoir. Refill it with fresh fluid and start bleeding.
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| − | I didn't have much luck with either Teflon tape, or sealer, seems that movement of the bleeder valve disrupts the seal. I used silicone grease that would move with the valve, due to the use of Dot 5 brake fluid. Maybe lithium would work with Dot 3 fluid. With the 3/8" vacuum hose I was using, I had to carefully regulate the vacuum source to keep from over running the 3/16" brake line, and causing more air in the suction line.
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| − | [[Category:Brakes]]
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| − | ==Alternatively==
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| − | Leave the engine bay alone, go to an auto parts store and buy a hand-operated pump *with* all these fittings or online from Amazon.com: $30 made of plastic resin, $35 for the brass version.
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| − | | + | |
| − | [[Pressure Brake Bleeder Set Up]]
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| − | Good post, if using manifold vacuum, do make sure you are using manifold vacuum at the sourcing port and not ported vacuum. Mechanics that don’t know the difference; probably shouldn’t be messing with this anyway. If you are using the manifold for bleeding the brakes, then this means the engine is running which is not always safe or efficient. This also means if the car is on the lift, you are moving the car up and down or using a ladder to access the car, which is just silly.
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| − | When flat stalling and doing the fronts and the car is on stands, and you open the door to start or pump the brakes etc…., you can tweak (bend) the frame. This is especially true on older Plymouths, and GM F-Bodies. I lost count of how many cars I have seen with binding drivers doors that were not caused by weak door pins or hinges, but by a bent frame because of a failed previous sloven repair.
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| − | To seal the jar easier if you make a jar as you described, use a mason jar. The lid removes, is easier to drill and seal the fittings and the top comes with a cast in gasket.
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| − | One of the biggest problem most mechanics make is forgetting to take the top off of the master cylinder. If you leave the lid locked down when you are trying to bleed..., the fluid won't flow. You don’t have to take the top all the way off, just open the top and loosely set it back down. This is also true of the cap style that screw off. Setting the top or tops back on the master loosely keeps dirt from getting in the fluid.
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| − | Another easy way to bleed is to use clear tube from the pet (fish) section of a discount store. The clear vinyl will snuggly fit over the tip of the bleeder, you can see the air bubbles, and use a horse syringe, 30 – 100 cc to draw out the fluid. These syringes do not have needles and are disposable. The pet section should also have the petcock valves designed to go into the clear vinyl, check back in the fish section. Its all cheap and disposable.
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| − | You can also remove a vacuum reservoir from a salvage car and use this reservoir as a portable source, use the clear tubing, and the petcock to open and close the line. You can then charge this with manifold vacuum, close the line and then shut off the engine before you start the repair of the brakes. This way you have portable vacuum without having to keep engine running.
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| − | Always bleed the brakes from the furthest point from master cylinder first. The master is typically on the driver side (left side) firewall so you would bleed in following order: Passenger (Right) Rear, then Driver (Left) Rear, Stop, come to the front, refill the Master, then bleed the Passenger (Right) Front and then the Driver Side (Left) Front. At conclusion check the fluid level, button up the tires, torque spec the lug nuts, remove the stands, drop the car, and then check pedal position, pedal travel and then test drive.
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| − | For rear drums you will need to reset the star adjuster prior to the road test, this is easy to do by driving in reverse and consistently lightly stabbing the brakes. This lets the star adjuster set the proper distance between the shoe facings and the drum.
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| − | I like using the hand vac because it has other uses in diagnosing other vacuum operated items, but I do use a jar like you mentioned. The "jar" that comes with the hand vac is too small and plastic and gets filthy after constant use. Using a mason jar, I can save the top I made and get a new jar and locking ring when it gets too dirty, or breaks.
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| − | You mentioned possibly using Lithium to seal the threads…
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| − | DO NOT do this. The only thing (chemical) that should ever make contact with brake fluid is the same type of brake fluid. This is why the OEM uses the copper ring as a line gasket at the caliper and all other connection are flare or double flare fittings. If you are having sealing issues in the bleeder threads, this usually means the threads or the bleeder is dirty or partially plugged.
| + | ==Tips== |
| | + | Another tip is to use clear tube from a home fix-it store (Ace, Lowes or Home Depot, etc.) or the pet (fish) section of a discount store. The clear vinyl will snuggly fit over the tip of the bleeder; you can see the air bubbles. The pet section should also have the petcock valves designed to go into the clear vinyl, check back in the fish section. Its all cheap and disposable. |
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| − | What you can do is get some fresh bleeder screws from the parts store and make pairs of these with the tubing already attached securely to use as fittings you keep with the bleeder setup you have. Most bleeders should be metric threads, all made prior to 1982 GM will be SAE, Ford and MOPAR is a toss-up as they purchased what was cheapest to get the car through the assembly line, but most cars after 1982 should now all be metric and there are only a few sizes of these.
| + | You can also remove a vacuum reservoir from a salvage car and use this reservoir as a portable source, use the clear tubing, and the petcock to open and close the line. You can then charge this with manifold vacuum, close the line and then shut off the engine before you start the repair of the brakes. This way you have portable vacuum without having to keep engine running. |
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| − | I think NAPA has all these in their Balkamp or Weatherhead line. I used to rebuild all the calipers and wheel cylinders, but with prices today, I just buy the “Loaded Pair Calipers” for the front, and new wheel cylinder for the rears if they are drums or new calipers if they are rear disk, (some cars don’t have Loaded Pairs for the rear).
| + | Always bleed the brakes from the furthest point from master cylinder first. The master is typically on the driver side firewall so you would bleed in following order: passenger rear, then driver rear (refilling the master cylinder as needed), then bleed the passenger front and then the driver front. At conclusion check the fluid level, button up the tires, torque the lug nuts to spec, remove the stands, drop the car, and then check pedal position, pedal travel and then test drive. |
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| − | It is also a good idea to just keep a modest amount of new bleeders in your toolbox anyhow. Most mechanics hate comebacks and a leaky old bleeder can cause this as well as a car accident due to failed brakes. When a customer drops a few hundred for a good quality brake job, there is no reason to nickel and dime them on reusing the old bleeders. It’s the same reason you use fresh valve stems when you change tires.
| + | For rear drums you will need to reset the star adjuster prior to the road test, this is easy to do if the vehicle is equipped with self-adjusting rear brakes by driving in reverse and consistently lightly stabbing the brakes. This lets the star adjuster set the proper distance between the shoe facings and the drum. |
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| − | Likewise new calipers and wheel cylinders come with new bleeders. Messing around with the old bleeders wastes time.
| + | ==Bleeder screws== |
| | + | You can use fresh bleeder screws to make pairs of brake bleeders with the tubing already securely attached to keep with the bleeder set up you have. Many bleeders are metric threads; all GM made prior to 1982 should be SAE; Ford and MOPAR is a toss-up; most cars after 1982 should be metric. |
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| − | [[Category:Undeveloped articles]] | + | ==Also see:== |
| | + | *[[Pressure brake bleeder set-up, homemade]] |
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| | [[Category:Brakes]] | | [[Category:Brakes]] |
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