Master Cylinder 1977 - Fluid Jumping

I had my master cylinder replaced and replaced some brake lines. It has had a very spongy pedal since then. I have bled multiple times but still the pedal is very spongy. The guy that replaced the master cylinder said that he bench bled. I thought that I would double check so I jacked up the truck to try to get the master cylinder as level as possible. I can see the master cylinder through the vent in the hood while pressing lightly on the pedal. While doing this fluid seems to jump up and spill over a little in the small bowl in the master cylinder. On occasion, some was spilling on the big bowl. Two questions:
1. Is this normal? or is this air still escaping?
2. Could I have possibly worn out something in the master cylinder through my multiple bleeds?

It does have power brakes - front disc, rear drum.

Thank you,
Jim

Yes, the master cylinder will squirt fluid until the piston passes the inlet port. Perfectly normal.

Air will make your brakes spongy but they will usually pump up and lift/harden after a few strokes. If yours are not able to pump up then it must be something other than air.
I have gotten a bad mc from the parts store before. It took me all day working to believe it was a bad mc but that is what it ended up being.

Thanks for the replies. The pedal will pump up. Just spungy and will take about half of the stroke before it feels like they are engaging.

I did have the front calipers changed at the same time. Any chance air can get caught up in the calipers?

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There's always a chance air is still in the calipers or even in the rear brake cylinders/lines.
I would check the calipers to make sure the brake bleeders are on the highest side of the calipers if not the calipers may be on the wrong sides and you'll need to swap them.
Also weak brake hoses can cause spongy feeling brakes as they swell when pressure is applied.

I wish I would have seen this post before I brought that other one back to life! I'll ask again here. On the metering/pro portioning block, do you have to pull the pin and keep it pulled out to properly bled the brakes? The old Ford factory Manuals say you do. Mine of course is stuck fast as far as I can tell. Other than that I'm having the same problems JimR is having. Ugh this is keeping me from getting the inspection done so I can be driving the Bronco. Thanks!