ABS Brake Accumulator 101

While doing a brake bleed on my 348 I noticed when finished, if I had the ignition on, but not the engine running, everytime I pressed the brake pedal, the accumulator pump would run briefly. Everbody knows that sound.. you hear it before you fire up the engine, but after the engine is running you can't hear it. It seemed strange that it ran at every pedal press, but who knows how it had been like that? If you're not bleeding brakes, you don't sit around with the key on pumping brakes.
Anyway, I started investigating, and if anybody's interested, here's what I found: the ABS and brake system is by Teves which I thought rhymed with "Jeeves", but is actually pronounced "Tev-ez". Similar systems were on a bunch of cars at the same time period.
If you Google "Thunderbird ABS 1989" you'll find a good review of the system by a Patrick Duffy. Turns out my symptoms were a sign of a dying accumulator. It's that black baseball-like thing you see when you open the hatch to get to the left front fender fuses. If the diaphram inside and nitrogen gas charge behind it aren't working right, then the pump has to run briefly with each pedal press which will shorten the life of the (presumably expensive as hell) pump. The good news is you can buy just the accumulator ball. I got one for a Thunderbird Supercoupe from a place called spinningwheelmotorsports.com for $150.00. It comes with installation instructions. It's VERY important to depressurize the old old one before removing. Pressures are over 1000 PSI. Now the pump only runs after 5 or 6 pedal pumps.
So next time you hop in your car, before you fire her up, turn the key on 'till you hear the pump run and stop, then hit your brake pedal a few times. If you hear your pump run each time, you know what to do...