Patrick03

Not sure which one to get for a dual master cylinder.

https://www.motiveproducts.com/collections/domestic-bleeder-kits

66BlkBB

What year master cylinder are you working on????

Patrick03

Well that is a good and valid question to ask. The car is a '64 with a single master cylinder. I bought a dual master cylinder, but can't remember what year I selected. Let me check the usual sites I buy stuff from and see if I can find my order. Otherwise, I'll check tonight when I get home.

Crunch527

I think this one...

https://www.motiveproducts.com/colle...nd-marine-kits

I have an older version that had the plastic adapter flange...it leaked like a bitch...fluid everywhere...I would have to create a "Mc Guyver" contraption to get enough clamping pressure on the flange and even then it would only hold about 5 psi. The hooks and chains aren't worth a damn.

The version above looks newer and appears to have a metal flange and therefore, this one may seal better...just know the underside of the master cylinder isn't flat and it makes it challenging to get good clamp pressure on the top of the flange if it leaks like mine does.

Besides that HUGE flaw, the system works ok.

gsholz

I had an older Motive bleeder with the modern European screw on adapter. After reading that the Motive adapter for the single '64 master cylinder does not work well, I built my own. I cut down onw of my wife's plastic cutting boards to a 4 inch square and screwed/glued a hose adapter into it. Using a C-clamp to seal with a foam gasket. Voila!

Jackfit

You may be better off with Speed Bleeders, they allow you to pump brake fluid out without letting air in.

I just did all four wheels by myself with no spills as I hooked up a hose line to bleeder , into a soda bottle.

Just add fluid as it goes down in MC...

Jack

JohnZ

I've used the Motive Power Bleeder for over ten years - here's my setup for a '67 dual-reservoir master cylinder. First thing I did was to throw the chains away and used a 6"-long piece of 1-1/2" square tubing to spread the clamp load on the adapter and a 6" C-clamp to provide the pressure seal to the top edge of the master cylinder. This is THE sure-fire way to bleed Corvette disc brakes; makes it a one-person job, takes about ten minutes (after removing the wheels).

bluestreak63

Throw away the chain and j hooks they give you. Could never get the cover on the single MC to seal. I use a couple of 4inch carpenters clamps. No more air leaks at the MC.

Crunch527

Spreading the clamping pressure is the KEY...

Welcome back John!!

Cheers,

Frank

Patrick03

Thanks for all great info guys. Think I'm all set now.


Patrick

DSR

I have a Motive Bleeder, but have not used it the last few times on my '65 with a dual master. I found that just opening a bleeder at the brake caliper, the system would drain the master cylinder in a few minutes without even pumping the brake pedal. Brakes work good.
Dave

dserge

I have used John Z's set up for the Motive bleeder and I love it. Best Corvette brakes I have had in years.

vark_wso

The Motive model 0105 adapter (like John's) will also work with OEM '65-66 power brake m/cyl's. The adapter ports will fall over the two open cavities, although not perfectly on-center. A large C-clamp over each opening will provide a good seal. C-clamp ends should be padded with something like a rubber cup or piece of leather, adding friction to prevent slipping on the curved bottom of these m/cyl castings.

GTOguy

I stopped using power bleeders in industry over 30 years ago. Simply not needed to do a great job. I bench bleed the master cylinder and gravity bleed the system. There's a market for everything, I guess. Pneumatic gasket scrapers used to be a big sale item, too, until a bunch of parts kept getting destroyed. YMMV..........

bluestreak63

But doesn't gravity bleeding take a while?

427/42566 coup

I use my wife and grandson's Right foot for bleeding brakes

DSR

like GTO guy said once you bench bleed a master cylinder . Bleeding the lines only takes a few minutes. I can't remember exactly it's been a long time since I had to do it. With a caliper bleeder open it would take maybe five minutes to drain the master cylinder reservoir.

bluestreak63

So I've bench bled my single MC, are you saying then I can just open up the bleeder, based on the sequence in the shop manual, drain the MC, but not completely, refill, close the bleeder and move onto the next one and repeat? Drain the MC, close the bleeder, refill, etc. and that will get all the air out? And it would take like 20 minutes?

DSR

Yes , worked for me. I have stainless lines but I don't think that would make any difference.

GTOguy

Sometimes it takes 20 minutes, sometimes it takes longer. But, yes. If the master cyl is bench bled of all air (I do mine with a syringe injecting fluid into the outlet ports on a half full reservoir until all air bubbles are gone....takes about one minute), all you need to do the entire system bleed is crack open a bleeder, leave the cap off the MC so you can watch the fluid, and let it drain out of the wheel cylinder/caliper nipple until you get a steady stream of drips and no air. No pedal pumping required. My '61 Corvette took less than 15 minutes to do, and it had been sitting for decades. As an ASE certified Master Auto technician, I can tell you, myself and all of the other professional techs I work with have no use at all for power bleeders.....we simply know better.