Yet another brake question

In reply to 44Dwarf :

Oo! That would be a delightfully straightforward answer...

In reply to Ransom :

My thinking is that it goes from free play to no movement in the last 1/2" travel, will check that this afternoon when I get home. That sounds like it indicates air in the system, which based on how many items have been replaced/removed is a distinct possibility, I have bleed the system probably 20 times since I have had this car.

In reply to 44Dwarf :

That would be a nice treat, I don't recall seeing a second hole on the pedal arm, but certainly worth another dive under the dashboard.

I am pretty sure there are actually 2 ways to adjust the pushrod on a second gen.  

There is the pedal adjustment as well as the rod itself actually being adjustable.  a half inch of adjustment is a METRIC CRAP TON.  I would expect the brakes to go from mushy to locked up (without pushing on the pedal) with that much adjustment.  A half inch of adjustment at the rod would be like 2 or 3 inches at the pedal.

There is something else going on here..

Can you try to gravity bleed?

Lemme get out my pictures and stuff...

44Dwarf said:

Is it possible you have a pedal from the manual brake version of the car? the pedal ratio is different.  You may just need to move the attachment point so the rod travels further per the pedal travel.  Some MFG put both holes in the pedal some don't.

44

I don't think there was a manual brake version of this car. Only different amounts of pistons on the brakes, but all had power assist as far as I know.

So after 2 seasons of chasing this problem it turned out to be something easy.  The brake light switch is adjustable and it also changes how far the brake pedal returns at rest. My son the auto tech figured it out in about 5 minutes today. It was adjusted all the way out, with it re-adjusted the pedal starts out a little closer to the floor thus having less overall travel. It will be so nice to have confidence in my brakes again. Thanks again to all the suggestions.  

OK, problem solved so my comment may be redundant .

All this talk of push rod adjustment for tavel is wrong.   It is only for pedal free play after the master cyl. has returned to it's rest position.  

Congrats on sorting it out!

Iceracer, the pushrod stuff was more about trying to sort clearly incorrect behavior than travel directly. E.g. sorting out whether the extra travel was because it wasn't fully releasing the mc, etc etc...

I'm kicking myself for not getting past "there's something funny going on", and want to kick Mazda for making the brake light switch affect travel.

iceracer said:

OK, problem solved so my comment may be redundant .

All this talk of push rod adjustment for tavel is wrong.   It is only for pedal free play after the master cyl. has returned to it's rest position.  

Go yell at a brick wall.  You will get more satisfaction than trying to explain that to the internet.  I've just given up.

How did adjusting the brake switch make the pedal have different travel in regards to car running or car not running?

If the brake switch was holding the pedal up, it should have had free play with the booster working or not.

The adjustment  moved how far back off the floor the pedal comes when it is released. It had been set to be at it's  farthest position possible. By moving out,  I now have less initial travel before the engagement point. It makes perfect sense  now, I just didn't  know to look for it. I had finally decided I was just imagining the way the old car pedal felt as with the brakes fully applied the pedal was at about the same point. I could confirm that as my "heel/toe"  method did not change.

My question is why didn't it have a ton of free travel with no vacuum assist?