I installed a SSBC rear disc conversion on my chevelle. Which it had all around drum brakes but i decided to go all around disc i still had the drum brake proportining valve on the car so when i went to bleed my brakes. I started to bench bleed the master cyclinder on the vise stand fluid ran threw the plastic lines no air bubbles. Master Cyclinder full of fluid i installed it on the car and started to bleed my front the front brakes bleed fine. Great fluid pressure so i went to the rear using a one man brake bleeding kit. But was not getting no fluid to the rear. So im thinking the portioning valve might be closed and not allowing fluid to get pass it so i took off the line at the portionting valve and no fluid in the line at all so i took off the line at the master cyclinder and no fluid was not even coming out the master cyclinder at all so started to pump the brakes and no fluid shot out of the rear line port on the master cyclinder at all. So i tried it on the front line port and fluid shot all the way across my garage so im thinking it was a bad master cyclinder and so i got another on and it did the same thing can anyone help me on this problem. Please excuse my puncutation i get tired on periods here and there

There is a stroke rod adjustment on the master cylinder input shaft. The rod may need to be moved for a longer stroke. Look at the rod from the brake pedal. Is there another position to move the rod if so try that. Coworker had the same thing happen on this setup.
P.S. Some people get upset about punctuation when you can barely read the post.