it's best to bench bleed it but you don't need to take it back off. it will bleed regardless.

If you have a system that's fighting you I use the vaccum pump and have someone push the brakes the old fashioned way. that always seems to do it.

 

I had some trouble with not getting fluid to the calipers when I replaced the master, and I solved it by pumping and holding the pedal, and cracking loose the line at the master cylinder, and then quickly tightening it.

Did you let the pin back out on the pressure differential/metering/proportioning valve after bleeding?

 

Is that a new type of valve and pin setup? I've never heard of loosening it at the hex fitting. I would think that would simply allow air into the system and not get you what you need.
You should be able to either pull, or push the pin (whichever way yours works) against the spring and hold it in place. Never knew you could loosen and re-tighten to hold it in place.

Just out of curiosity, do you have a pic of your proportioning valve? It's new you said? Is it an aftermarket brass thingy shaped like the original?
I thought those were all "pull type" valves rather than pushing the pin.

Good luck.

Paul

 

 

with the one I just put on my son's truck, I pulled the the switch out and installed a plastic pin that came with the proportioning valve and bled it. The pin holds the valve from moving so it doesn't block the lines your not bleeding. Ihave seen the tool for the type your talking about and I believe it pulls it out.

 

Yes, I've never seen one from the aftermarket that pushed in. All the ones we've sold over the years like that have been pull-out types.
The tool alans77 is talking about is also for bleeding, but it's for the electrical switch (dash warning light) to keep the shuttle centered.
The spring loaded thingy that you are supposed to pull out (the push type were only factory on the heavier 250's and 350's I believe) are a "delay valve" that holds off pressure from getting to the front brakes for just a moment while the rears not only have time to perhaps catch up, due to needing more travel to the friction surfaces, but also to stabilize the vehicle during braking maneuvers. Think along the lines of trailer brakes being used to stabilize a heavy towed load by applying them first, before pushing the main brake pedal. Same concept to keep the rear from fishtailing.

But that same feature also has the possibility of limiting flow to the front brakes when bleeding. Hence the instructions to pull (or push) the valve pin.
The reason I prefer manually adjustable valves now, is that the aftermarket brass ones were a pain in the butt. The generic ones never had the stock size threads in them, so adapters were always needed. And the delay valves were prone to leaking. Often!
If the combination valve was made for a specific vehicle, then the fittings should be fine. But the leaking valve was still a possibility.

Paul