Imperial Journey

I’m a glutton for punishment. That’s the only possible explanation!

My plan is to get the Imperial back on the road in the summer of 2020. This means having the car mechanically complete – body/paint and interior will be later projects.

Having completed the front end work, the next step is to do the rear end. At a minimum this meant removing the rear end/differential and replacing seals (the differential is currently leaking). If I’m going to do that, I might as well have the rear end completely rebuilt and make sure there are no surprises buried inside.

After pulling the rear end out I was studying the bottom of the car and mentally planning the routing of exhaust, installation of new sway bar, dealing with the gas tank, etc.  As I mentioned in the article Shiny Bottom I had only painted back to the rear wheel wells. I realized that I would never be able to do the rest of the bottom after putting the suspension, exhaust, and gas tank back together…

Krud.

Allow me to re-iterate: KRUD! Krud on a shingle with a side of despair!

So, pull out the heat gun and scrapers and go back to one of my most hated jobs: removing undercoating.

The same old drill:

1. Heat and scrape for bulk removal.
2. Wire brush and sand for more removal.
3. Clean with solvent and scrubbing pads.
4. Final clean with solvent and rags.
5. And, finally, paint!

Did I mention that this is on the bottom of the car?

Of course, step 4 and 5 revealed rust that had been hidden… So, working in the cramped space under the car:

• Make a cardboard template.
• Make another more refined cardboard template.
• Make yet another cardboard template.
• Use the cardboard template to mark out the rusted area to cut out.
• Use the cardboard template to mark out the patch panel to cut out. Bend the patch panel to the proper contortions to match the body.
• Fit the patch panel.
• Make another patch panel and try fitting it again. Repeat until declaring in frustration “close enough!”.
• Weld the patch panel in place.
• Discover that the rust extended beyond the patch. Make a new patch to extend the first patch.
• Repeat for the next rusted area.

Fortunately all of these rust spots were relatively small and in the areas you would expect – overall the car is remarkably solid and rust-free for its age. But this was still a nuisance and work I hadn’t planned for.

Part of the challenge here is that I’m trying to do this right – precision fit the patch panel and butt-weld all the joints. It would be a lot faster and easier to cut the patch panel over size, overlap it over the hole, and weld it in place. After all, this is the bottom of the car and no one will ever see it!

Doing it the right way here gives me practice for work that will show, so it is worthwhile taking the extra time and frustration here for better results later on when it will show. At least that is what I keep telling myself…

After all of this, do one last cleaning pass with solvent, dig out the painting equipment, and spray the paint! As usual, two coats of epoxy primer and two coats of paint.

The biggest surprise was that I had exactly enough paint to finish the second coat. I was positive that I would run out before that point. Instead, I ran out when doing the last bit of touch-up. Why do I suspect that I will pay for this later?…

That brings us up to today: After 6 weeks of torture, the entire frame and bottom of the car has been painted! No more paint or body work is required at this point – I can now focus on putting the car back together and getting it on the road.

Next: Tanks for the Springs

The Imperial has a large heater box mounted on the firewall inside the engine bay. This heater box contains the air conditioner evaporator, heater core, fresh air inlet, and blower fan.

The heater box is made of a fiber reinforced plastic – you can tell by the strands of fiber visible on the surface. As you would expect of 50 year old plastic in the hot under hood environment, it has not aged gracefully. Fortunately it is still solid. Unfortunately it is looking tired and weathered.

The obvious thing to do is paint it, like I’ve been painting everything else in the engine bay.  The issue with this is that the textured surface would look horrible – the fibers would print through the paint and make it look like a poorly prepared surface. This closeup shows the visible fibers.

You can’t sand it, as this would just expose more fibers and damage the existing finish.

Preparation for paint would require multiple coats of high build body primer, with sanding between each coat. The final result would be a completely smooth surface – which would look good, but would not look original.

Searching the Internet, I found references to surface renewal treatments for plastic. These claimed to actually soak into the plastic, retaining the original surface texture and details. I decided to try Eastwood’s Plastic Resurfacer, which claims to “reflow and resurface faded and chalky surfaces”.

After thoroughly cleaning the heater box I applied several light coats according to the instructions.

The end result is quite good – the heater box still has the factory texture, but now looks like a new piece. Time to install it and move on to the next project!

Next: More Shiny Bottom

To improve the handling of the Imperial I’m upgrading the front sway bar to 1″ (from the factory 3/4″) and adding a rear sway bar.  While going from 3/4″ to 1″ doesn’t sound like that big a change, the new bar is over three times stiffer than the old one! Torsional rigidity goes up as the fourth power of the radius, so small changes make a big difference.

I had ordered the new front sway bar over a year ago. Now that the front suspension is in place I can install it. The process is to remember where I stored it, unbox it and check all the pieces, read the minimal generic instructions, and test fit it.

And, of course, it doesn’t fit…Not a complete surprise; it is hard to get anything for an Imperial, and some tweaking to make it work is part of the “fun”. You have to periodically remind yourself that you are doing this for fun!

The mounting hardware puts the front of the sway bar right in the middle of the lower strut arms, which are a critical part of the suspension. I spent several hours trying multiple different ways of mounting the sway bar, but had interference no matter what I tried. Even when I dropped the front of the sway bar for clearance I still had problems with things hitting at some point during suspension travel.

After taking a break – of a week or so – I decided that the next step was to get the car off of the jackstands and onto its tires so that the suspension was in its normal position. Part of the problem was due to trying to fit things with the suspension drooping as far as possible.

With the car at a normal ride height, it was time to extend the front mounting hardware. The sway bar came with a 3/16″ mounting plate, another 3/16″ spacer plate to clear the bolt head, a bolt, a sleeve, and two suspension bushings.

Front sway bar mounting bracket as received

Lowering this involved getting a longer bolt and adding washers and other spacers. I kept adding spacers and trying to install the sway bar until it worked. I finally reached the point where I could install the sway bar and it didn’t hit anything through the entire suspension travel. Life is good!

Well, sort of good. I ended up with two 1/2″ nuts and six washers as spacers. While this worked, it looked like – and was! – a complete kludge.

Sway bar bracket with spacers

Nope, this wasn’t going back on the car! Time to head over the the WorcShop and use some of the equipment I mentioned in the previous post. If you have a machine shop, use it!

The bracket with spacers provided all of the dimensions I needed. I started off by cutting some 3/8″ steel plate to size and drilling holes for the base. Why 3/8″? Because it is overkill and I found a chunk of 3/8″ plate in the scrap bin. Next was to cut some 3/4″ diameter rod to length and drill it and tap it in the lathe. Finally, use the 300 amp shop welder to weld the rod to the plate. And voila – a custom sway bar mounting bracket!

Custom bracket

Mount everything on the car for one last trial fit:

Test fit on car

In this picture you can see the front bracket as well as the rear bracket – the rear bracket can be identified by the two yellowish grade8 bolts.

While the front brackets were fine, the sway bar was just a little too wide in the rear. I decided to space out the rear a little by replacing the 3/16″ mounting plates with 3/8″ mounting plates. Yes, I may enjoy playing in the machine shop just a little bit…

Complete set of brackets

A bit of paint and the final assembly. One more item off the list and on to the next!

Final installation on car

Next: Plastic Fantastic

The previous post covered the installation of the new disk brake rotors and calipers. The next step is to hook everything up.

As previously mentioned, I’m upgrading from the original single master cylinder to a dual master cylinder. This both provides additional safety in case a brake line or wheel cylinder fails and also provides a proper balance between front and rear brakes.

Since the power brake booster is almost sixty years old, I sent it out to Power Brake Booster Exchange for a rebuild and installation of a new master cylinder. They confirmed that I’m going with front disk/drum rear brakes and provided the correct master cylinder. I also had them return the original master cylinder – I’m saving all of the original parts in case someone wants to return to a factory configuration in the future.

Once the booster and master cylinder were installed it was time to run new brake lines. I’ve had brakes fail on older cars due to pin-hole leaks from rusty brake lines. Fortunately the failure was gradual, but it left me stranded overnight on the side of the road on a long trip. This has lead me to a philosophy of completely replacing all parts when doing brakes on old cars.

In the past I’ve used regular steel brake lines. They work well, but they are difficult to bend and prone to rust. I’ve read about new cupro-nickel brake lines – an alloy of copper and nickel, which is used on many new cars. Cupro-nickel is completely corrosion free, so it will never rust out. It is also supposed to be easy to work with. Unlike steel brakelines which come in straight segments which are typically 5’ or 6’ long, cupro-nickel comes in 25’ rolls. This allows you to run a single continuous brake line with no fittings – another way to minimize leaks!

The cupro-nickel line is indeed easy to work with. I tried a couple of different techniques for bending it, and ended up doing most of the work with a set of bending pliers which have radiused jaws:

These pliers make it easy to make bends wherever you need them without crimping the brake lines.

Armed with these tools I first routed the line for the right wheel. This required forming a large arc to match the front cradle of the engine, and then routing the line past the A-frame mounts, over the frame rail, and up to the bracket for the flex hose. This job went surprisingly well.

Using steel lines this would have required two or three pieces – and I probably would have had to re-do it two or three times! The cupro-nickel is easy to tweak and adjust. I’m pretty well sold on these new brake lines.

The front brakes require a T-fitting to split the line from the master cylinder into lines to the left and right wheels. So, decide on a good place to mount the T-fitting, adjust the brake lines to it, and install everything. Of course, you have to remember to install the nuts on each segment of line before you flare the ends…

Speaking of flaring, brake lines require a double flare – which I hadn’t done before. So I purchased a fairly highly rated flaring kit, cut some short lengths of brake line, and started making practice flares. I wasn’t happy with the results – the flares were frequently off-center and poorly shaped.

There is another style of double flaring tool that is supposed to be easier to use – almost idiot proof, in fact. This style is more expensive and requires separate tool for each size of line. Since stopping is important and the tool was less than $50, I decided to give it a try.

It turns out that the reviews were right – the tool is easy to use and produces good flares. It is self centering and self adjusting: just follow the directions and it “just works”. The ability to flare a line on the car is surprisingly useful – run and fit the line, cut it to length, flare it in place, and tighten the fittings.

Speaking of fittings, I mentioned that it is necessary to install the nut before flaring. I remembered to do this, and was rather proud of myself. When running the lines to the master cylinder I just stuck the end of the line in the master cylinder port to get everything dry fitted. I then installed the nut, flared the end – and discovered that the nut was the wrong size! This was the same size nut that worked everywhere else, but not on the master cylinder.

Fine. Dig around the collection of brake line nuts and find one that fit. Cut the flare off of the line, remove the old nut, insert the new nut, and flare it again. Fortunately there was enough line to still reach the master cylinder, so this wasn’t a real problem.

Now being paranoid, I found another nut the same size and tried it in the other port on the master cylinder – and it didn’t fit! So, dig around in the fittings, and find another one that fits. NOW install the nut on the line, flare it, and screw it into the master cylinder.

After thinking about this for a few minutes, it almost makes sense. Using different size fittings on the ports prevents people from switching the front and rear brakes, which would result in seriously unbalanced braking. Something else to watch out for on future brake jobs…

In any case, everything is now hooked up to the master cylinder:

The last bit is the rear brake line, running along the frame rail. The silver wrap on the line is a stainless steel spring that protects the brake line from rocks and other hazards. It is used everywhere the lines are exposed to flying rocks and similar threats.

At this point the brakes are almost done. I need to add brake fluid and bleed the air out of the lines. I also need to rebuild the rear brakes. The rear brakes are a challenge due to the special tools needed to remove the rear drums. I may just pull out the whole rear end and have it rebuilt.

Next: The WorcShop

5,000+ pounds of classic American steel requires substantial authority to both start and stop. The massive 13″ drum brakes that came from the factory were up to the task when the car was new. Today is a different story, unfortunately. The braking was actively scary, with the car pulling badly to one side.

Yes, rebuilding and adjusting the brakes would make a big difference. But you would still have the factory single master cylinder. So I decided to upgrade to front disk brakes and a dual master cylinder.

Fortunately a disk brake conversion kit is available from AAJ Brakes. They recommended getting the basic kit and buying the standard parts locally – it seems that shipping for ~50 pounds of hub, rotor, calipers, and other assorted pieces gets expensive. The basic kit includes a pair of massive caliper brackets along with assorted bolts, spacers, installation instructions, and a parts list for sourcing everything else from your local parts store.

The parts list calls out an interesting collection of parts, including 73-74 Ford F100 rotors, 71-76 Impala calipers, and 76 Monte Carlo brake hoses. I purchased all of the parts and put them on the shelf.

After getting the rest of the front suspension assembled, the new caliper brackets installed easily. That should have been my clue that things were about to go sideways…

I pulled the F100 rotors off the shelf, opened the box, and noticed that they were removable rotors. Which is great, except that you need a hub to go on the spindles. So, back to the parts store to get a set of hubs to go with the rotors.

Open up the new hubs, position them over the spindles, and have immediate questions. The inside of the hub is huge – there is no way that the bearing and seal will fit it, and it doesn’t seem to match the spindle at all. Also, there are a set of splines inside the hub that don’t seem to match anything on the car. After staring at this for a minute, the light bulb clicks on: these look like 4wheel drive hubs!

So, back to the parts store. The counter guy says that these are the only hubs listed. I ask him to check for 2wheel drive. His next words were “Would you look at that! As soon as I specify 2wheel drive it brings up a completely different listing.”

The 2wheel drive hubs were an integrated hub/rotor assembly that fit perfectly. Actually installing them was a 15 minute job, with 10 minutes of that spent packing the wheel bearings with grease.

Here you see the new caliper bracket, rotor, and caliper. You can also see the rough routing of the brake line. A future article will cover routing and installing the brake lines and finishing off the stopping system.

Next: Stop It! Part Deux