toledo uses compressed air for suction... I wonder if this is a better way than having the pressure on the MC.... ? Might be less messy, and you would not need a specific adapter...
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I use a MytiVac to suck the brake fluid through the system, starting with the right rear.
Jason
We use a MytiVac Pro for our initial bleed but find that we still have to manually bleed the last bit and sometimes it takes an initial drive to gather all the small air and manually bleed it out.
I use similar vacuum pump for the main fluid exchange.. but just like Carey states, I still follow up with the manual bleed process --person 1 pumps brake pedal 3-5 times and holds while person 2 opens bleeder (with hose to bottle) then closes bleeder. repeat as necessary. (usually at lease 2x /wheel)
Yes, start at wheel furthest from master cylinder then move to next furthest. (usually that's passenger rear, driver rear, passenger front, driver front but there could always be an oddball exception)
We tried, mightily, to use a Multi-Vac in the "Old-School" days and sometimes it worked, OK but most of the time we had to follow that up with someone pushing the pedal and another turning the bleeder. This was when my Dad had a bunch of school buses. Bleeding the right rear on a bus that has a brake line 3-1/2 MILES LONG is a pain in the Patoutie.
We got a powered brake bleeder from the Snap-On guy for exorbitant bucks but, MAN! Did it ever work!
Fill it with a gallon of new fluid, hit it with 15 lbs. of air pressure, attach it to the master cylinder and start bleeding. Even on a school bus with looong brake lines, all four wheels could be bled in under an hour with no follow-up pedal pushing.
I built a home brew pressure brake bleeder from a bug sprayer a few years back and it works just fine on my speedster with a 1-quart load of fluid. Several outfits on Amazon sell them in the $50 - $75 range.
@Gordon Nichols we too used a pressure bleeder, screw to the reservoir, add a little pressure, and pump a bunch of fluid through the system. It works, in my opinion and experience, better than vacuum. That said, the manufacturers have changed the threads on the reservoir cap several times. They come with a cap installed, so to them it doesn't matter, you always have the proper cap, but doing this in volume was an exercise in futility playing "guess the cap of the month"...
@chines1 posted:@Gordon Nichols we too used a pressure bleeder, screw to the reservoir, add a little pressure, and pump a bunch of fluid through the system. It works, in my opinion and experience, better than vacuum. That said, the manufacturers have changed the threads on the reservoir cap several times. They come with a cap installed, so to them it doesn't matter, you always have the proper cap, but doing this in volume was an exercise in futility playing "guess the cap of the month"...
I agree I had a leak on my cap once so thus my request… and the roulette game is no fun.
@chines1 GM was the worst, sort-of. They cast the reservoir as part of the MC with a flat metal or molded plastic cover over the fluid, depending on year. They would change the dimensions/shape of the reservoir from time to time so, of course, your old bleeder cover no longer worked. 🤬 Ford trucks had a similar concept, but different and incompatible and needed their own bleeder adapter. Our Snap-On bleeder came with a box full of covers and adapters to fit just about anything - Literally a couple of dozen different ones when we only needed two or three. After my Mom passed and I cleaned out the shop, I found that box with almost 2 dozen unused adapters. 🙄
Snap-on later fought back with one, Big-A$$ cover, roughly a rectangle, that would fit just about anything but clamped on with this Rube Goldberg clamping contraption that would have worked great as a vacuum seal, but under +12 psi it always seemed to leak.
This is the time of year I would start my "Summer Job" of driving new school buses from the factory in Highpoint, NC, to Worcester, MA. It was a 16-hour ride at the governor max speed of 55mph, or a 14 hour ride once we pulled the vacuum hose off of the governor and plugged it with a BIC pen. Then we could cruise at 70-ish. 😉 GM and Ford got about 7-8 MPG at speed (350 or 351 gas engines), and International Harvester always got 10 mpg no matter what with a 400 CI mill.
@Gordon Nichols posted:driving new school buses from the factory in Highpoint, NC, to Worcester, MA. It was a 16-hour ride at the governor max speed of 55mph, or a 14 hour ride once we pulled the vacuum hose off of the governor and plugged it with a BIC pen. Then we could cruise at 70-ish. 😉 GM and Ford got about 7-8 MPG at speed (350 or 351 gas engines), and International Harvester always got 10 mpg no matter what with a 400 CI mill.
Another similarity Gordo, I drove school buses in HS.. first year my assigned bus was an IH, manual & but did have power steering. The next year I was assigned an automatic... until some else's bus needed service. Then for some reason I got the 'service bus' and they got mine. Again manual and this time no power steering either 🙄 (at least the governor was tuned up to 45 on that bus.) As it was a "paid" ride back & forth to school, mpg didn't concern me. 
Yeah, those 45mph governors were some Federalista’s dream of safety and probably caused more accidents than they saved. Imagine one or more buses going somewhere on an Interstate and obstructing traffic at 45mph. New bus rolling frames shipped with governors as standard from the factory until a majority of states outlawed them as a hazard. The dealer we got buses from in Massachusetts (where I had a Summer job) disabled them on all new arrivals. All it was, was a plate fitted under the carburetor with a pair of vacuum-operated throttle plates in it that would restrict air flow at higher speeds to keep the bus below 45mph. It also slowed the bus to half speed on long uphills. MAJOR PITA!!!
@chines1 posted:@Gordon Nichols we too used a pressure bleeder, screw to the reservoir, add a little pressure, and pump a bunch of fluid through the system. It works, in my opinion and experience, better than vacuum. That said, the manufacturers have changed the threads on the reservoir cap several times. They come with a cap installed, so to them it doesn't matter, you always have the proper cap, but doing this in volume was an exercise in futility playing "guess the cap of the month"...
When I completely redid my brakes and clutch, I did both ends (pressure at the master, suction at the slave/drum) and that worked pretty well. But in the end, I still had to do a manual 2 man bleed to get both pedals just right.