Permatex

My Alfa is a mostly completely original car, meaning that it’s never been “restored”, not in the sense that classic cars are restored with all-new cosmetics and completely overhauled mechanicals. Yet with 65,000 miles on it (and counting), there have been maintenance and wear items needing attention.

The car is wearing about 90% of the paint and 100% of the interior with which it left the factory. The engine, gearbox, and rear axle are likewise the same assemblies that Tony, Vito and their fellow factory workers installed. During the past 51 years, the car has gotten new tires, brakes, belts, hoses, bulbs, shocks, clutch, tune-up parts, and fluids. I’m very conscious of my role as “steward” of this car, and hope that when it eventually moves to its next owner, the preservation efforts will continue.

As you may know from reading this blog, I’m not shy about putting several thousand miles a year on it, and if the paint gets a little worn or slightly chipped from my enjoyable time behind the wheel, so be it. But I would never consider repainting the car. Likewise, should a major engine component fail, I’ll repair it as necessary, but I’m not going to seek out a larger engine from another Alfa. I’m continually striving to maintain that balance whereby I get to enjoy the car while only fixing what needs fixing.

Earlier this year, I discovered that the reverse light didn’t work. The truth is, in the 5 years I’ve owned the car, I don’t think I had ever checked the back-up light. Its inoperative status gave me the impetus to remove the light assembly (there’s only one, below the rear bumper) and get it working again. The overall goal was not to replace it, but refurbish it, reusing as many of the original components as possible.

**Bezel, housing, lens, and broken hardware after removal from car**

The first challenge presented itself when two of the four fasteners snapped during removal. The clear lens was held in place by two Philips head screws, and half of one stayed in the housing. The housing itself used two studs with nuts, and one stud broke in half. Unlike the recessed screw for the lens, the broken stud projected far enough above the housing that a pair of locking pliers got it out the rest of the way.

**Closeup of housing. Note broken screw on left, and hardened white gasket.**

The gasket beneath the lens had been some kind of rubber that had turned to stone. It’s likely that it had never been disturbed until now. The chrome housing was somewhat pitted, and looked like it would respond to some metal polishing. The rubber bezel, mounted between the housing and the painted rear valence, would be treated to a trick I successfully deployed during the Isetta restoration: using Meguiar’s #40 Rubber Reconditioner, the bezel would be submerged and soaked for several days, hopefully returning some of the rubber’s pliancy.

**I had my doubts about salvaging the lens; the old gasket was that hard.**

While that sat in its bath, I tackled the removal of the old gasket. This was more of a fight than I anticipated. Not wanting to damage either the housing or the lens, I started with a plastic scraper, but made little progress. Next, I tried various solvents, attempting to soften the material. WD-40 had a minor effect on it, so I kept at it with that, fearful that anything stronger would also harm the lens. The most effective removal tool turned out to be a single-edge razor blade, but this took time. Eventually, both surfaces were rid of the hardened white material.

Instead of purchasing a replacement gasket, I fashioned one from sheet cork which I keep just for such purposes. I tacked it in place using non-hardening gasket glue. Three days in the conditioning bath brought the rubber bezel mostly back to its former glory.

**I’ve had great success with Permatex #2 non-hardening sealant; note LED bulb in place**

My best shot at finding the metric hardware I needed was the local ACE Hardware store, Post Hardware on Route 22 in Somerville NJ. They had the correct screws for the lens, but not the studs. So instead, I bought bolts with the right thread pitch, and hacksawed off the bolt heads. Viola! Metric studs.

**There’s a reason they say that ACE is the place**

The broken screw was drilled out, and retapped with my metric tap and die kit. The studs were installed with a dollop of thread-locking compound. The old incandescent bulb was replaced with an LED bulb from CARiD.com. As the repair books state: “reassembly is the reverse of disassembly”.

**I may use the tap & die set infrequently, but it’s great to have**

As you can see, the back-up lamp burns brightly. There’s just one more thing to report, but before I do, I must ask you to think like an Italian. You see, when I first tested the refurbished assembly, it still didn’t work. And that’s when I remembered: in 1967, as far as the Italians were concerned, a driver didn’t need the back-up light to illuminate every time you put the car in reverse! After all, it would provide little or no help in daylight. But if the headlamps are on, indicating it’s dark out, THEN a reverse lamp would prove helpful. So the back-up light is wired to come on only when the light switch is on. I’ll be taking a night cruise just to confirm how well I can see behind me….

**Nice and bright (as long as the headlights are on)**

My Mazda Miata workshop manual is an aftermarket publication, not the official factory book, but it’s been very helpful. It’s well researched and written, and the photography is adequate. It’s written in the style of “we’re in a shop with an example of this car, and we are documenting our actual repair procedures”. This approach certainly lends an air of credibility to the book.

In reading the section on heater core replacement, this service manual states (and I’m paraphrasing): “the entire dashboard must be removed from the car. We know of no work-around”. The manual was published in the mid-1990’s, at the dawn of the public’s access to the Internet, and it is obvious that were it to be updated today, information gleaned from various online forums would be incorporated, including a heater core work-around.

I was able to remove and reinstall my Miata’s heater core WITHOUT removing the entire dashboard. In fact, an underdash panel held in place with two screws, a heater box cover held in place with two screws, and several hose clamps were the totality of what was removed for successful heater core retraction. (The driver’s seat was also unbolted and taken out, only to provide greater comfort when working under the dash.)

**Old (foreground) and new (background) heater cores. Old one has been cut; new one, not yet.**

The secret to this success came from an online forum, www.miata.net. For those who dismiss the Internet (especially automotive forums) as a waste of time, populated by flamers and trollers, one must wade through the waste to find the gems. And this was a gem: a poster at the Miata forum had discovered that cutting one heater core pipe would reduce total work time by hours (in my case, days). I used a Dremel tool to cut the pipe, and I had the old core out and in my hands, dashboard intact.

The concept is this: Mazda built this heater core with one short pipe and one long pipe, soldered to the core itself. The short pipe uses a piece of hose and a clamp to connect to a pipe running through the firewall. The long pipe goes directly through the firewall, and it’s this long pipe which necessitates dashboard removal, so that you have room to swing the core around and maneuver the long pipe out. However, if you cut this long pipe, then join the two pieces together with a hose and clamps, there’s no need for the major disassembly and reassembly.

**Hoses and clamps on pipes will be connected once core is in place**

(Interesting sidenote: for the NB (2nd generation) Miata which started in 1998, the factory switched to TWO short pipes, for easier removal of the core.)

The tricky part during reinstallation was determining the EXACT best place to cut the new pipe. First, it is not in my nature to take a hacksaw to a new $150 part. Should that part be defective, its warranty would be, as they say, over. The goal was to cut the pipe as short as possible while still leaving room for two hose clamps. I temporarily installed one hose clamp to ensure that I’d have room for it, then drew a line along it, which became the cut line. It worked.

**Permatex 300: non-hardening sealant designed to work with antifreeze**

In the interest of doing this job so that it would not ever leak, I spent an additional $4 on another factory heater hose so that I would have the perfect ID hose for the job. I also bought a $3 jar of Permatex sealant designed to work with cooling systems (and waited 12 days for its arrival) to be absolutely sure that I’d get no drips. I hate drips. It was overkill, but I’m glad I used it.

**Auxiliary drive belt, in spite of looking pristine, was replaced**

The new heater core slipped into place easier than I anticipated. Working in the tight quarters under the dash was a pain, but a #2 Philips screwdriver bit in a ¼” ratchet wrench (instead of a screwdriver) was the trick to get to all the Philips screws. While this was going on, all the underhood work was wrapped up, including all new coolant hoses, new thermostat, and two new auxiliary drive belts. As recommended in the forum post, the car was started and run before buttoning everything up, to make sure it was all dry. It was.

New core in place: harness was main obstacle

Friday of last week, the job was completed, and I drove the Miata for the first time this season. It welcomed me like an old friend. It’s nice to know that I can look forward to a summer’s driving season without worrying about cleaning the windshield after every drive.

richardscarblog

All automotive, all the time

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