Brake pedal too stiff

[Wombat]

Today my brake pedal suddenly became too stiff with no free play. I can feel that the car is not rolling freely, in fact when I jack it up I find that all the wheels have significant resistance to turning by hand. There was no warning or special event, this just suddenly started. I don't want to drive the car until this is sorted out because I don't want to overheat the brakes.

My beetle has four after-market wide-five disk brakes from the wonderful John Sherman at Volks Conversions (Australia), with a dual-circuit master cylinder. I haven't adjusted/bled/touched anything for about a year so there is no recent messing about which could have caused the problem.

Any ideas what could be causing this?

[Piledriver]

Small rocks, mud and junk and combinations thereof get into the pedal area, despite out best efforts, even on a T3 with the cover.
There is a pedal stop bolted to the floor with a lip, and stuff can get wedged between that and the pedal arm stop area.

If the pedal has no free play, the pistons won't clear the fluid entry ports and cylinder cannot vent//refill.

Break out the shop vac and a common screwdriver to use as a pick to break up the crud.

If that doesn't fix it and adjusting the pushrod doesn't help (mark the original setting or measure with it removed) it could be junk in the brake fluid blocking the ports. (least likely, esp with an otherwise fresh system)

[Ol'fogasaurus]

How long since you looked at the soft lines in back? They can swell, when old, even to the point of swelling shut.

Moisture in the lines (remember that brake fluid is usually hydroscopic) can also do a number on you. Look at the brake fluid and it should be clear. Inspecting/bleeding/flushing the system on a regular basis (not daily but, depending on where you live might mean yearly or a bit longer) is something often forgotten. Moisture can also cause the MC or the slave cylinders to become inoperative or sluggish.

Anyway, in case you hadn't thought about it, a couple of things to check.

Lee

[rrb6699]

check your e-brake too. if you want to feel this same thing just pull up on your e brake and your pedal will be a lot "higher" when pressed.

[Marc]

Small rocks, mud and junk and combinations thereof get into the pedal area, despite our best efforts, even on a T3 with the cover.
There is a pedal stop bolted to the floor with a lip, and stuff can get wedged between that and the pedal arm stop area....

99% of the time this is the cause. If the "compensating ports" (where the fluid enters from the reservoir) aren't uncovered with the pedal "up", pressure builds as the brake fluid warms/expands, leading to brake drag and the brakelamps staying on...and the drag only heats the fluid further, so the worse it gets, the worse it gets

The M/C pushrod length is factory-adjusted and as a rule should not be tampered with until all other potential problems have been ruled out. There should be 1mm (.040") freeplay in the pushrod, which translates to 6mm (about ¼") at the pedal.