Category: Customization

Last week I performed some thorough diagnostics on the motor: checked the vacuum, tweaked the tune on the carburetor, looked at the timing, etc. In the end, the high rpm hot misfire persisted—maybe even got a little worse, as I managed to coax a backfire during one test run.

While I’m not 100% convinced it’s an internal engine issue, I strongly suspect it. (It’s unlikely, but it could still be an ignition issue in the distributor or plug wires.) Digging deeper, I pulled the valve covers and the rocker arm assemblies. There were no bent pushrods and nothing looked terribly amiss at this level, except perhaps an odd wear pattern on the rocker for the #8 exhaust valve. That cylinder was also the low outlier when I did a compression test some years back.

The diagnostic flowchart goes down the rabbit hole at this point, but one strong possibility is an out-of-spec camshaft. So, with help from my son, the engine came out of the car yesterday.

I’ve pulled engines from at least 5-6 cars over the years, and each one of them has been a challenge in some way. The tight fit in the Thunderbird engine compartment had me relying on every bit of that experience. (And I gained even more in this evolution.)

Getting the hood and accessories off was routine, and with the radiator out, the front of the engine is remarkably easy to access. Likewise when the hood came off things like the throttle arm and bellhousing bolts—notoriously difficult to reach—were right there for the taking.

Underneath, the exhaust flange bolts are buried in deep, greasy recesses, and even though these had been removed a few years back when the transmission came out, they were completely frozen. I ended up removing the 16 exhaust manifold bolts instead. (Many were, surprisingly, only finger tight! I guess the exhaust guy I used doesn’t believe in lockwashers).

While lifting the motor, we got hung up on the transmission cooler lines (hate those things, but no damage done) and the motor mounts snagged on the now free-floating (but unremovable) exhaust manifolds. After some head-scratching, we worked it free and the lift had just enough height to clear the radiator support. (The car being up on ramps to facilitate work underneath.)

There’s a paradox to the engine removal in the T-Bird. The motor has to come up  a few inches to clear the motor mount studs, but it has to come forward an inch or so at the same time in order to clear the studs on the torque converter. It’s difficult to do both at once. In my case, the converter came partway with the motor and some 4 quarts of transmission fluid poured out the bellhousing until I pushed it back in. I’m not sure if that’s normal on a COM transmission or if I mucked up the front transmission seal.

In any event, with the lifting out of the way, the real work is just beginning.

 

I still figure to be about two weeks away from backing down the driveway.

Space in the garage is gradually clearing out as parts are being assembled, but the real change will come when the dash goes back into the car. That monster has been lurking in the garage for far too long–as has the old doppelganger, which is heading for the scrapyard when this is all done.

Moving the old dash around the garage, I managed to damage both the defroster ducts, which were made from cardboard originally, but have transformed into a brittle, crumbly substance. The new dash had one duct left on it, also damaged. Reproductions are produced, but they are about $100(!) new, about a third of that for good used, so I’m making an attempt to restore what I have. They are hidden, so don’t have to look pretty.

My initial thought was to reinforce the ducts with fiberglass and resin–which would probably work, but I was steered in the direction of epoxy instead of resin, potentially thinned down with acetone. In theory, it will penetrate the old cardboard and bond better.

The same person also directed me to TAP plastics for materials. I stopped by to get some epoxy in bulk and discovered it was a DIY candy store: full of tools and materials for projects I hadn’t even thought of yet. I left with epoxy . . . and a few “extras.”

Over the last week the new dash was painted/dyed, the instrument cluster was installed and the stainless trim was snapped back on. I also pulled the wiring harness off the old dash. I will replace the light bulbs and repair the wiring at the alternator gauge, then tap into the harness for power to a modern radio/head unit. With the restored ducts and the replaced wiring, the dash will be ready to go back in the car.

When I purchased the T-Bird–wow, almost a year ago now–the double-jointed throttle linkage was flopping around under the hood and the gas pedal didn’t connect properly with the linkage under the dash. I cobbled together a fix and left the matter for another day.

Today, in fact.

Missing from the linkage equation was a throttle stop plate, which attaches to the upper bellhousing bolt. It doesn’t connect to the linkage, just gives it something to bang up against. (Why it was designed this way, I don’t know; it seems overly complex to me.) I got a replacement from Thunderbird Headquarters after confirming with the helpful folks on the VCTI forum that I was on the right track.

Turns out, this is a lesson in the dangers of non-stock modifications. The top bellhousing bolt came off easily, even with the linkage in place, but I couldn’t get the stop plate to fit at all. The transmission on my car is not original, and while it belongs in the same family as the one that should be there, it’s a poor fit. Like everything else that bolts to the tranny, the stop plate needed to be modified. I removed a substantial bit of metal to clear the bellhousing and install the plate.

I installed and removed both the plate and the linkage assembly a few times before getting the fit right. It’s a long stretch down there behind the motor. Even with long arms, it was a tiring reach.

 

The finished assembly.

Once correctly in, there was the matter of a connection to the carburetor. It’s a straight rod from the end of the linkage to the throttle actuator, but it has to be the right length. Too short and the gas pedal doesn’t properly connect. Too long and you can’t open the throttle all the way.

I “fabricated” a new connector rod from straight aluminum rod; basically cutting it to length and notching it where the set screws attach to provide a little extra security to those connections.

The throttle response on my test drive was vastly improved. I was just going to go around the block, but I realized immediately that before, even with the gas pedal all the way down, I was at half-throttle at best.

To the expressway!

Wow. This car is fast. Much faster than I thought. Next stop, though, the gas station.