Page Forty-Nine - Stop and Steer

 

It’s been a minute, but here’s what I’ve been up to.

Disc Brake Calipers

It might surprise you that sixty years, with however many of them spent outside or in various soggy environs, can grow gobs of rust, shocking I know.  Alphie’s calipers were pretty much frozen with rust, but the Organ Donor’s were abjectly fossilized.

Rusty with one piston freed.  The other piston is solidly stuck!

With enough leverage and skinned knuckles, I was able to pry Alphie’s calipers apart.  And I thought I would break down the Organ Donor’s for extra parts, at least for the bolts, silly man.  But no amount of force was breaking apart what chemical reactions had welded together.  The Organ Donor’s calipers are ballast at this point, blunt murder weapons.

The hardest part was freeing the pistons from their holes.  As you may know, whereas modern disc brakes use floating calipers (meaning they slide on pins, allowing them slide back to center after each peddle push), Alpine calipers are fixed using a piston on each side of the disc with a balance port between the caliper halves to equalize the hydraulic pressure, which is how they re-center.

Now, if a piston is stuck, you can use air pressure to push it out.  BUT after one piston busts loose (which it did rather violently, making one Alpine mechanic jump a wee bit and make noises), the other piston stays comfortably snug in its hole.  The air pressure now simply vents out the hole where the freed piston once lived.

I tried various methods of holding the free piston in place to get air pressure to the other side, but to no avail.  Finally, and because I could see that the old pistons were manky and because I could order shiny new stainless-steel ones, I decided that drilling a hole in the stuck ones (remember, there are two calipers) and tapping them with threads offered the best chance to free them from fossilized bondage.

I drilled and tapped threads in the hole.
A bolt pushed the piston out where nothing else would

My concern was that I would 1) drill through the piston and into the caliper wall, 2) strip the threads, requiring me to drill bigger holes and 3) muck up the bottom of the piston holes with a bolt pushing out the stuck piston.  As it happens, 1) I didn’t drill into the caliper wall because I was watching it very closely, 2) the threads held dutifully, and 3) neither the drilling nor the bolt pushing against the caliper wall mucked up anything.  Go team me!

I sacrified the piston, but there's only a small scar on the caliper bottom

With lots of bead blasting, powder coating and cast-iron paint (because the color of the cast aluminum powder was too bright for my tastes), the calipers are happily clean and ready for new pistons and gaskety sealy parts.  (The shiny ss pistons are backordered, but when they get here, everything will be spanking!)

Brake Servo

Power Brake Booster for my American readers.  Brake fluid is icky stuff; it corrodes almost everything it contacts, collects water, turns to jelly, and generally makes a bloody mess.  Tearing down the servo takes many rags and a few spray cans of brake cleaner.

Just a heads-up, there’s a big spring in the can part of the servo that, when you loosen the last screw on the backing plate, will shoot everything out the back, making your favorite mechanic jump and make noises, again, just FYI.  And there’s usually loads of smelly old brake fluid in there from decades of leaking seals.  It smells terrible too.

Grungy and gross, the dissambled parts of a Girling brake servo

Cleaning everything up is gross but simple.  Removing the valves from the valve body is the big chore.  Again, the brake fluid and everything it corroded in the aluminum valve body makes an impressive glue, and the parts are small and won’t survive heavy-handed prying and banging.  I soaked the valve body with all its innards in WD 40 for a couple of days and used mostly air pressure to break everything loose.  The lower valve jumped out easily.

But the high-pressure control valve, or more specifically the end plug behind the control valve, at the back of the valve body was stuck like a mosquito in amber.  Soaking didn’t work.  Spraying copious WD 40 in it and on it didn’t work.  Brake cleaner didn’t work.  Puffing 120 psi of air pressure, nothing.  What finally worked was gently slipping a very thin feeler gauge between the valve body and the end plug O-ring braking the adhesion between the aluminum wall and the O ring’s rubber,  then pumping in lots-o-air pressure finally blew it out.  Oh, and when it finally blew out, your mechanic jumped and made noises yet again.

Cleaned painted and powder coated parts with a (second) rebuild kit

Finally disassembled, I cleaned, bead blasted, powder coated and painted all the parts (from two servos so that I had more parts from which to choose – yeah, I did the feeler gauge/air pressure, jump when it broke loose thing twice.  It went a bit easier the second time because I knew what to do.)

Another heads up, don’t cluelessly rip out the big leather seal that seals around the can because the rebuild kits don’t have a new one.  (One should at least glance through the rebuild kit before going at it.)  I had to order a second much more expensive kit that had a leather seal in it.  Thanks Harmon Classic Brakes for having a kit with a leather seal.  Eh, live and learn.

Spanking!  (We'll have to wait until I have
Alphie running to know if it works!)

With new seals, new stainless-steel hardware and slickly painted/powder coated parts, I built me a shiny new (looking) power brake servo!

Steering Box

Tearing down the steering box is simple but be sure to count the ball bearings!

The bearings at the top and base of the steering shaft are loose bearings that spray out everywhere when you take the bolts out.  I should have been expecting it, but nope.  I looked in the parts manual to find out how many bearings went where.  They’re a big pain to get back in too, just FYI.

Dissasembled and cleaned

I finally found a trick.  I would load the individual bearings for the top of the shaft and use a spring clamp at the bearing race to hold the bearings in place while I loaded the lower bearing in their race.  I used one bolt and a huge fender washer to hold the bearing race and shaft in place while I loaded it in the car.

Sporting some slick paint and powder!

So, (just FYI) with the engine and front suspension in place, you can’t wiggle the assembled steering box, shaft, and outer shaft sleeve into the hole in the firewall, I discovered.  I had to remove the outer shaft sleeve, insert it into the firewall hole (with new grommet in place) and thread the shaft through the tight space between the engine and wing (fender) well and into the outer shaft sleeve to get the steering box nestled into its bracket on the frame.

Sparkling and finally in its spot

With one bolt through the steering box and into the bracket, I removed the bolt and fender washer, slid the outer shaft sleeve in place and fitted the three 5/16” bolts to secure the whole thing back together.  By the way, fit the steering column into its bracket under the dash before tightening all the bracket bolts because I had to wiggle the steering box in its bracket to get the steering column seated in the right place under the dash.  It’s the little stuff that makes ya crazy(er).

Installed and ready to impale

Next, I’ll tell you about getting fossilized U joints out of a drive shaft that sat under a tree for thirty (plus some) years.