I was just reading "the book" and wondering about the right bleeding sequence for my '71 Skylark. It says to start with the wheel closest to the MC.. I always assumed to start with the farthest one... What is the right way for our cars?
I have gone to gravity bleeding and do two at a time. I start with the back, and then move to the front. Works well, with just me.
I have bled a lot of brakes. Furthest to closest, closest to furthest. 2 person, no person gravity, no person vacuum bleed and no person "Speed bleeders" and no person "Speed bleeders". By the fastest and most efficient has been 2 person Speed bleeders (ten minutes) but without an extra person, it takes about 20 minutes, and that's moving slow (getting under and back out is the longest when your on retirement wages...) Use a small tube and a catch, crack the bleeder about 1/2 turn, press stroke the pedal a few times and your done. I did "go back around" and found it was unnecessary. The little buggers are worth every penny.
My friends with 442's claim they have to use a tool on the proportioning valve to hold the switch. I never did that. Anyone here have to?
If you have disc brakes in the front (cant find one that fits the drum)it will prevent the brake light from illuminating
https://www.opgi.com/brake-systems/...alve-bleeder-1964-88-gm-vehicles-ch31499.html It goes I'm the place of the cap with the wire on it.
They tell you to do that in the Buick Chassis manual, AND, it isn't the Proportioning Valve, it's the Hold Off Valve.
Nope. Correctamundo, it was a combination valve, Hold off, Brake Warning, and Proportioning valve in one.
Yes, you can get away without depressing the pin. It makes bleeding the front discs a bit easier if you do though.
When I did the front disc brake conversion I used the tool, only because the proportioning valve was dry to start with. I don't know if it helped or not though, as they bled out fine with it in there.
It really depends on what you're doing. If you've replaced all the lines, then a Motive pressure bleeder sans fluid (and mess) is the way to start, finishing with a foot guy and bleeder guy.. If replacing a caliper or wheel cylinder and the system doesn't run dry, a foot and a bleeder guy still is the way we do it, in no particular order. If replacing a master cylinder, dead-head bleed on the bench first. On a GM system with the above proportioning valve, sometimes you'll have to re-center the shuttle valve to get the red brake light off. Usually you you push in on the metering valve stem to bleed but many times it's seized, or push in after if you forgot and find it seized anyway. Then you'll have to open an opposite end bleeder to re-center the shuttle valve to get the light off. If you think these are hard, try bleeding a 19+ 1500 Silverado!
We have to make things up as we go sometimes. Even today's service information serves for comedic value at times. Case in point, we have had at least 3 19+ Silverados in the shop from body shops who have replaced the frame. Following brake bleeding procedures to the T would have had us replacing the ABS/Power assist "still" under the hood for $3k+. We knew that wouldn't have helped. Thinking outside the box got it done. I'm not sure how the "muffler monkeys" are going to handle these vehicles in a few years.
Unless the valve gets slid into the contact position (brake light is on, goes off when you disconnect the lead at the combination/splitter valve) then there is no reason to fuss with it. I don't recall ever having to depress that valve to bleed the brakes on that vintage A body. It's also checked when you get weak/no fluid at the front/rear brakes while attempting to bleed the brakes. In 1969/1970 the balance valve was located in the splitter block on the frame on all models, regardless of disc or drum brakes. A change occurred for the balance valve in 1971, when the combination valve assembly was introduced on the disc brake equipped cars. The 69/70 disc brake cars used a Hold off valve mounted under the master cylinder that was eliminated.. this valve assembly also had a rubber cap to reset the valve, but again, I have never had to depress it that I can recall.. With a pressure/vacuum bleeder, I always start with the wheel farthest away from the master cylinder, that being the right rear.. the left will bleed out very quickly, the only air left is in that individual LH line from the splitter valve on top of the rear end. The front uses individual lines once you get past the splitter/combo valve, so I have never seen it make any difference which side I started with. Pressure/Vacuum bleeders are the only way to go.. if you do any amount of brake service work, you need to own one.. they are inexpensive. I have had both the pressure pot that pushes fluid and the vacuum bleeder type that sucks it, the pot goes a little quicker, but you have to be careful putting the adapter on the master cylinder, so brake fluid does not squirt all over your car.. No brake pedal stomping required, as long as you properly bleed the master cylinder before you start. JW
