When you release the pressure in the Motive tank  the air at  the top of the pressurized master cylinder reservoir will be forced  back down the hose and bubble out of the tube that goes into the fluid.  That's what I meant.   Pinching  off the hose will prevent this, or just don't open  the Motive tank until bleeding is done, which means having a good amount of fluid in the tank when you start.   It's a great product and I've used it many times on all my vehicles.  I also use it to pressurize the Vanagon cooling system for leak testing.

Stuart

-----Original Message-----
From: Neil N <musomuso@gmail.com> 
Sent: Tuesday, May 5, 2020 9:49 AM
To: Stuart MacMillan <stuartmacm@gmail.com>
Cc: vanagon@gerry.vanagon.com
Subject: Re: Questions about brake bleeding

HI Stuart.

On 4/11/17, Stuart MacMillan <stuartmacm@gmail.com> wrote:

> .... If you have to add more when you crack the cap you'll bubble air 
> into the fluid remaining and will need to wait several hours or toss it.

I'm not familiar with the Motive pressure bleeder.

re: "add more". Are you referring to refilling the Motive tool and not in regards to adding more fluid into the master cylinder reservoir?
i.e. when cracking the cap on the Motive, air bubbles get introduced into brake fluid in the Motive tool?

I use a home made "air" pressure bleeder. I've not noticed air bubbles created in the master cylinder reservoir when topping it up during the bleeding process.

Thanks,

Neil.

--
Neil n

VE7TBN

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