brake bleed sequence

What is the standard brake bleeding sequence including the master cylinder?

Reply to
norm
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Master should be bench bled. Bled totally independent of the system. Generally done with master in a vise, but can be done with an assistant if the master is already in the car. There is a kit, plastic fittings & hoses that connect to the master. Fill the master with fluid, submerge the hoses & pump the master till all air bubbles stop. Connect master to the system, top off with fluid & begin bleeding at the farthest wheel first. Right Rear, Left Rear, Right Front & Left Front. Check Fluid level in master after each wheel to insure master never goes dry.

MIke

Reply to
MCL

Caveat: Exact sequence is going to vary by vehicle.

For example, on my current ride, that means bench-bleed and connect the MC, go to right rear and bleed it, then right front, then left front, and all done. Yes, I'm completely aware that this sequence totally ignores the left rear - and with good reason: Late 70s/early 80s Mazda

626s had a weird rear brake setup - Instead of a bleeder on the left rear, the hole that would house a bleeder on that wheel is connected to the hard-line that runs the full length of the rear axle to reach the right rear wheel, with a lone bleeder on the right side - no "Tee" in the line at the axle like most other vehicles - brake line routing is MC

--> LR --> RR --> bleeder, meaning that bleeding the right rear bleeds the left rear at the same time.)

Reply to
Don Bruder

The logic I've always heard is "furthest wheel from the master cylinder first." (After the master cylinder itself.) I guess this might mean a mirror image of our procedure when dealing with home-market cars from right-hand-drive countries.

As you aptly mention, the shop manual supersedes conventional wisdom. Speaking generically without regard to any particular make/model/year, it should especially be consulted with regard to antilock systems, just to see if they have managed to complicate even this fairly simple task.

The original poster is probably well aware of this, but it seems worth mentioning anyway: after putting it all back together he should start the engine in park or neutral, verify a normal pedal feel, and make those first few stops from low speed under the most forgiving conditions available. That "Earl said it's sorta like steppin' on a plum" feeling is deeply ingrained in muscle memory, as it probably is for a lot of us, and I'm glad I went through this embarrassment in the privacy of my own driveway before assaulting the public roads!

I'd further recommend the Mityvac hand vacuum pump

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or something of that nature to the homemechanic, though there are various pet procedures for solobrake-bleeding and some of them are cheaper. Maybe the tube-and-jarmethod works if you're more coordinated than me or something. It comeswith a thick booklet about other ways the ability to pull a bit ofvacuum on demand can be useful, mostly underhood. Cheers,

--Joe

Reply to
Ad absurdum per aspera

And I thought I might be the last C.W. McCall fan left on earth :)

"We went down and 'round and 'round and down till we run outta ground and bashed into the side of the feed store, in downtown Pagosa Springs..."

Reply to
Don Bruder

I looked at Earl an' his eyes was wide His lip was curled and his leg was fried And his hands was froze to the wheel Like a tongue to a sled in the middle of a blizzard And I said Earl I'm not the type to complain But the time has come for me to explain That if you don't apply some brake real soon They're gonna have to pick us up with a stick an' a spoon

Reply to
komobu

Snip>

That "Earl said it's sorta like steppin' on a plum" feeling is deeply ingrained in muscle memory,

unsnip>

Wolf Creek Pass, I love the tune, "sorta rolled around and lit the cuff of Earl's pants", "But them chickens were stacked to 13'9". Hoo boy, what a ride!!!!!

Seroiusly, don't end up in the side of a feedstore in downtown Pegosa Springs, by not adequately testing the brakes after the bleeding, Like ad states.

Reply to
Knifeblade_03

I ALWAYS step on the brakes as hard as I can (with the engine running, if the car has PB) before even taking the car down off the jackstands, after doing any substantial amount of brake work. If you're going to blow a line/hose/whatever, better to do it in your driveway than in a panic brake situation.

I'm not a big fan of the Mityvac, but I love my Motive Products pressure bleeder, I've used it on everything from Porsches to Studebakers. Makes bleeding easy and a one man job. I always use a length of windshield washer tubing over the bleed nipples, dangling into an empty 20 oz. bottle, to a) keep the brake fluid from eating the paint on the backing plates (yes, I am one of those guys who cleans and paints everything that I work on.) and b) allow me to see air bubbles, or lack thereof, coming out of the wheel cylinders. I also put vacuum caps over the bleed screws after I'm all done to keep them from rusting and seizing (if you want to be elegant, your friendly local VW dealer sells little rubber caps for just this purpose, which are a little more substantial and also easier to R&R with your fingers.)

good luck,

nate

(just bled the brakes AGAIN in my '55 Stude last weekend after swapping from a 3.31:1 open rear to a 3.73:1 limited slip... I bet I have the cleanest brake fluid of anyone I know! And what's worse, I still have to detail the LF backing plate, which means I'll have yet another bleed to do in the future!)

Reply to
N8N

I always put the snorkel into the bleeder hole and blast out any brake fluid then blast that with air then cap it to keep it from rusting.

Reply to
Scott Buchanan

Some cars have Dual Diagonal brakes. Left Front and Right Rear on one circuit Rt Ft + LR on other. Theory, if you blow out a hydraulic system, you still have one front, and one rear brake.

Gravity bleeding rocks, jack up front, open rear bleeder, let gravity expel the air. Close rear bleeders, jack up rear, open front bleeders. Takes about 10 minutes per end to get air, but it does go !

Reply to
Paul

doesn't work with bottom hinged pedals :( master cylinder needs to be a couple inches higher than the wheel cylinders...

nate

Reply to
Nate Nagel

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