1953 Cadillac 60-Special "The Muskogean Phoenix"

[kudims]

Interesting video, and a very beautiful car. So it looks like at least for this video anyway, that you started in June of last year?
 How long have you been working on your car?
 Excellent results!

 Rick

We purchased it in early June 2023. Everything before brakes and propeller shaft was done before April 2024.
Then, April-May 2024 - brakes, suspension; June 2024 - engine. And more is coming...

[Cadman-iac]

We purchased it in early June 2023. Everything before brakes and propeller shaft was done before April 2024.
Then, April-May 2024 - brakes, suspension; June 2024 - engine. And more is coming...

I was wondering, because of all the work you showed, I knew it wasn't easy and probably took a while to do.
 It'll be like a new car when you're done. Great job!

 Rick

[kudims]

I was wondering, because of all the work you showed, I knew it wasn't easy and probably took a while to do.
 It'll be like a new car when you're done. Great job!

 Rick

Probably it will look like a new car with a subtle hint of patina 

[kudims]

Continuing with the engine topic

For those of you who watched the video I posted above, this post should be straightforward. For anyone who hasn't, the short version is: there was an oil leak at the rear of the oil pan, and it needed to be fixed.

What can leak at the rear of the oil pan?
The "obvious" suspect is the rear main seal. I installed a two-piece neoprene seal instead of the traditional rope packing. Imagine my surprise when a $45 seal started leaking. No time to sulk, though: we have to drop the pan again and solve the problem.



I removed the rear main bearing cap, pulled out the seal. Visually, it looks okay, but the mating surface between the two halves appears melted or deformed—possibly from insufficient assembly lube. I used engine oil instead of grease; maybe a thicker grease would have been a better choice.



Not sure if you can see, but the seal's edge is deformed.



Waiting for the "Sneaky Pete" rope-seal installer from Amazon was not an option, so I fabricated my own out of stainless steel. This is the blank...



...and here's the almost-finished tool.



It hooks into the rope packing like so. The frayed edges had to be taped up, or else it wouldn't pass through the channel above the crankshaft.



When pulling the rope seal in, you have to rotate the crankshaft so you only fight friction from the block side.



Overall view of the work area. Nice to see everything is still clean.



Do not trim the rope packing flush; gently push it back in with a thin screwdriver or chopstick-like tool to ensure a proper seal. Nothing should protrude beyond the mating surface.



Same procedure for the packing in the main cap.



A drop of sealant on the ends of the rope, plus red anaerobic sealant on the main cap parting line.



I reused the old pan gasket since it wasn't torn. Cleaned it thoroughly and added some sealant.
Reassembled, took a test drive... and found oil trickling down the rear of the pan again. My "joy" knew no bounds.

I started Googling the topic of rear seal leaks on 331 and 365 Cadillac engines. Folks try all sorts of tricks: layering gasket material under the neoprene seal for a tighter fit, or just throwing up their hands—how can it leak again right after a rebuild? The only solid tip I found was that a Cadillac rear seal = a Chrysler 318 rear seal (with slight modifications).

Fel-Pro makes the Chrysler seal, which gives me more confidence than the artisanal seals marketed specifically for 331 Cadillacs. Plus, it's $12 instead of $45.

So I placed an Amazon Prime order for:

FEL-PRO BS 40245 Rear Main Seal Set
FEL-PRO OS 5363 C-2 Oil Pan Gasket Set
Lisle 27000 "Sneaky Pete" Tool
Meanwhile, I removed the pan and main cap yet again, thoroughly confused.



I had a theory about why the rear leaked, and this scene indirectly confirmed it. The rope packing is bone-dry.



A dry rope can't possibly leak streams of oil. You'd see oil residue if that were the culprit—but there's none.

Leaving you in suspense for a moment, we move on to removing the upper half of the seal.



The tool.



Thread the corkscrew into the old seal.



Pull it out like uncorking a bottle (at least I've got experience with that).

Note that many people write about loosening other bolts of crankshaft to lower it down. Never do this, if your transmission is mounted to the engine! It can bend or brake the input shaft and bearings + seals




The new neoprene Chrysler seal.



Extra "ears" need trimming.



Install instructions.



The seal halves have a "lock" shape, unlike the simpler butt-joint on the "artisanal" Cadillac seal.



This time, I smeared grease on the seal lip and crankshaft surface, checking 10 times that the seal was oriented correctly—lip facing into the engine.



Now I hope the mystery is solved: The oil pump supplies oil through the rear main bearing cap into the block's oil passage with no dedicated gasket or seal in that spot. The only thing stopping oil is precision machining, but let's be honest, even the best machining can't guarantee zero leaks—especially in the highest-pressure area. So (my theory) the oil was seeping between the main cap and block, then either entering the seal area and leaking out or going straight to the pan gasket interface and pooling at the lowest point by the rear seal.
Ideally, you'd have a machinist cut a groove around that main cap for an O-ring. I just used red anaerobic sealant around the mating surface.



New pan gasket.



Pan cleaned to a shine once again.

Tests so far have gone well. In previous attempts it would leak immediately. Now it's dry on the engine side, but I found a separate leak from the front transmission seal (or it may have been there all along, hidden under layers of grime and oil). No big deal, I'll have to pull the transmission and replace that seal. Work twice, oh well.



Ideally, it should look like this: clean, dry, and comfortable to work with.

After 7 months and 500 miles driven on a highway, the rear end of the engine is still dry. So, it makes me confident that I have found the route cause for leak. Please spread this knowledgeable tip among Cadillac owners




And this is the oil I use. High-zinc for flat bottom lifters is a must



I compiled a list of parts and local prices. As for the labor, you can judge for yourselves. I'll just mention that having a shop replace a rope-style rear main seal alone can cost around $1,000.

[kudims]

Fixing the Transmission Leaks

In our ongoing saga, the last episode ended with some encouraging news about curbing the rear main seal leaks. At the same time, however, it became clear that the Hydra-Matic is leaking from the front. Not just seeping or dripping, but almost pouring out.

In modern automatics, a front leak would typically point to a failing front seal. But in a 1953 Hydra-Matic, the culprit could be:

(a) The gasket between the crankshaft and flexplate
(b) The gasket between the flexplate and the converter housing
(c) The transmission front pump gasket
(d) The front seal
There's no way to know for certain beforehand, so I went ahead and bought an entire seal-and-gasket kit for $80 (versus the $15 single front seal). No harm in having extras.

Removing the Transmission



A peek at the gasket kit.

The transmission weighs over 100 kg (it's all cast iron—bellhousing, tailhousing, and main case), so you need a serious rig to remove and install it.



This Amazon-sourced transmission-jack adapter has adjustable tilt—absolutely critical, as you'll see.

Buckle up—here we go.



The car is lifted about 18 cm (7 in) off the ground. From experience, that's usually enough to access Phoenix's "abdomen." The weird cap on my head? It's an incredible piece of gear I used to underestimate. With it, you can stand under any kind of oil shower, or even rest your head in an oil puddle, and your hair stays protected.
I drain out the fresh, clean fluid (nearly 15 L) into a clean container, remove the driveshaft, starter, unbolt the left exhaust downpipe (otherwise the flywheel cover won't come out), remove the filler/ dipstick tube, speedometer cable, shift linkages... that should be everything.

Next, I unscrew the 28 bolts that secure the converter housing (the "torus" or "torque converter") to the flexplate.

Then I change into clean clothes and climb inside the cabin.

Accessing the Top Bellhousing Bolts



Under the carpet, there are two access covers for the top bellhousing bolts. People on the forums call these "lost technologies of an earlier civilization," and I can't disagree.



The covers themselves, being removed for the first time ever.



A jack under the transmission, plus a second jack (with a plywood crosspiece) under the engine oil pan so it doesn't get dented or scratched.



Unbolt the rear transmission mount and slowly roll the jack backward. Unlike modern transmissions, once those 28 converter bolts are removed, the converter itself only moves rearward by about 1–2 mm. Past that, you have to shift the transmission back and lower it so the input shaft can pull out of the crank bushing.





Commencing Apollo-Soyuz separation.



Gradually lowering it, passing through the dense layers of the atmosphere. A thin paper gasket sits between the converter housing and the flexplate, which has disintegrated into flakes.



How you feel after such a procedure...

Disassembling the Converter



The "torus" can be taken apart. The turbine wheel is held by a nut; the pump wheel by a snap ring.



Converter housing.



Damper springs. By the way, leaks can also come through these rivets.



Removing the bellhousing. This lets me thoroughly clean and paint the upper area, which was unreachable when the transmission was in the car.



Cleaned and painted the top of the transmission too, since we're here. Finally got to the seal that needs replacing.





Might as well wash and refresh the inside of the tunnel. Following 1950s GM practice: drips, runs, and uneven coverage are all "factory correct."



The extracted front seal, with its original part number.



Transmission without the front seal. Notice it has three shafts. They sure don't build them like this anymore.



Installing this SKF 25950 seal.





Lubricating the seal bore with plenty of red grease. The seal's inner area also needs lube because there's a cast-iron sealing ring inside (similar to a piston ring) plus a conical surface for compressing that ring. Must be installed carefully—no scoring or ring breakage.



A perfect example of why you need a tilt-adjustable platform. The X-shaped crossmember won't let the transmission drop straight down. You must angle it forward under the engine before rolling it free of the frame.



Using grease to hold the new converter gasket in place. The converter only fits one way, thanks to two alignment pins—one is 3/8 in in diameter, the other 5/16 in (about 10 mm and 8.5 mm). You can try to misalign them, but you can't.



This thin paper gasket required hours of meticulous scraping to remove the old remnants. The flexplate and converter housing have several circular grooves that interlock when bolted together, forming a reliable labyrinth seal once the gasket is compressed. Sealant is a no-go here.

Tightening the 28 Converter Bolts

After reattaching the transmission to the engine, the fun really begins: you must torque 28 bolts (5/16 in, ~8.5 mm) to 54 N·m (40 ft·lbf) in about five passes. Specifically:

Turn the flexplate to hand-tighten each bolt until it contacts the split lock washer.
Torque pass #1: 10 N·m.
Torque pass #2: 20 N·m.
Torque pass #3: 30 N·m.
Torque pass #4: 42 N·m.
Torque pass #5: 54 N·m.

I've never torqued 8 mm bolts this high. Admittedly, they are extremely strong, but I had to use a 9/16 in socket on a 1/4 in-drive ratchet plus a universal joint and extension—because there's no room for a standard wrench or larger socket.

After spinning the flexplate until I was practically dizzy—like a carnival ride—I reassembled everything else by feel, half-asleep...



Sandblasted and painted the crossmember matte black.



Beauty can be ruthless.



Time for testing!

The test drive and further driving showed zero leaks from both engine and transmission, which makes me happy - time and money spent for worth.

[Roger Zimmermann]

Nice job! On my '56 & '57 cars, I did more or less the same, but without the fancy transmission's support.
Just a small explanation: your car don't have a torque converter, but a fluid coupling. A torque converter is multiplying the engine's torque thanks the third member, the stator. This is why your transmission has 4 "speeds" because the fluid coupling cannot do it. 

[kudims]

Nice job! On my '56 & '57 cars, I did more or less the same, but without the fancy transmission's support.
Just a small explanation: your car don't have a torque converter, but a fluid coupling. A torque converter is multiplying the engine's torque thanks the third member, the stator. This is why your transmission has 4 "speeds" because the fluid coupling cannot do it. 

Fair comment. Yes, I know this, but for the sake of simplicity and familiar wording, I used that term.
Thank you for following the topic, Roger.

[kudims]

Rear Taillights

They're in good shape overall, but still needed to be removed, disassembled, cleaned of oxidation, rewired (the cloth insulation had deteriorated with age), then put back together and reinstalled. The left taillight, which flips open, required a bit more attention—its spring had weakened over time and no longer held the flip-up piece securely in the open position.



A taillight unit that's already been serviced and reassembled.



Taillights from 1951 through 1953 are the same. All the lighting components were supplied by Guide. I have, of course, newly fabricated lenses even with "Guide" embossing, but I will replace them only after the original lenses become fade and totally cracked. Now the idea is to show the original car in it's 72 years glory.



New protective cloth insulation where the wiring rubs against the filler-neck boot. First, I wanted to replace the clamp with a stainless one... But then I understood that I want to keep this original non-plated, from bare metal. It's not rusted.



The flip-up mechanism.



A couple more shots.



Adding two washers under the spring solved the issue of not staying open.



Reinstalled and tested.

Fog lamps and Headlights



Fog lamps housings were sandblasted and coated with a hammer-finish enamel. The housing itself is solid and rust-free. Usually, what I see on the web, is totally corroded.



New cloth wiring re-soldered.



Turn signal, parking light, and fog light.



Reassembly process. Here I made new stainless clamps for original rubber seals



The cover with a new gasket.



Front view.



All-new bolts and washers, 100% identical to the originals.



Appears to have been dip-painted at the factory, leaving an unpainted spot (likely an air pocket) inside. I left it as is—after 70 years, there isn't any rust. I just touched up the edge locally.



Both headlights have new wiring in a new cloth harness. Unfortunately, the original rubber wiring seals cracked, so I had to replace them with a modern ones, as I didn't find the true refabrication of original seals. Not a big deal, though.



Halogen sealed-beam headlamps (the type where the entire lamp is replaced, not just the bulb).



Installed.



Here's how it looks from inside. I replicated the factory markings with red and yellow paint.



Connector block on the left fender, with a matching one on the right side as well.

[Dave Ventresca]

is that original chrome on the taillights? Dave

[kudims]

is that original chrome on the taillights? Dave

Yes

[kudims]

New Exhaust, Part 1



New stainless exhaust from Waldron



Mufflers



Hangers and stainless clamps



Unpacking



Resonators (all 60-Specials must have them)



Inside



Put all together









Full length tailpipes (no cuts)

Of course, this will not be installed "as is". First, there will be a full underbody and frame cleaning, sanding, and painting to make it look as close to the original, as it came from the Fisher body in 1953... But it seems that I will not be able to repeat the same poor quality. However, will try my best.

[kudims]

Exhaust: Pre-requisites

The exhaust system was ordered back in the spring 2024, and I received it in early summer. Obviously, you can't just take and install a new exhaust system.



On a hot morning, September 29th, I secluded myself in the garage and started the process. The American "feature", which I've seen many times, is to weld exhaust pipes rather than connect them with clamps. During disassembly, cutting is the only option. I didn't want to use an angle grinder, so I cut everything with a Makita cordless multitool.



The left exhaust faced the same fate.



Condition of the rear exhaust pipes.



This is the so-called "Heat Riser," which originally had a valve that directed gases from the left manifold to the right through a channel in the intake manifold to heat the carburetor. As the engine warmed up, the bimetallic spring straightened, and the valve fully opened, redirecting gases from the left cylinder head to the left exhaust tract. This system isn't necessarily unreliable, but for Texas, it's even harmful. A new Heat Riser for a 1953 Cadillac costs around $500. And, yes, the gas is different today and needs much less heat to evaporate...



Then began a monotone and painful cleaning process. From every crevice of the frame, I dug out thick debris that even Dry Ice Blasting couldn't reach. This is just a small portion of what was removed—a very dirty job.



Once all the hidden areas of the underbody and frame were cleaned of dirt, I used about 5 liters of xylene and an untold number of paper towels and rags to degrease the frame and underbody for further work. A dozen of different toothbrushes were utilized )))



The body was originally primed at the factory with Red Oxide Primer. In some places, the primer had worn off, leaving a light layer of surface rust on the body.



I sanded off the remnants of the primer using 100-grit sandpaper.



Here are the copper air conditioning pipes running along the right side of the body.



Right side: openings for the exhaust system.

Since this is not my first restoration project (I've started playing with these cars back in 1995), I have practiced different ways of preparing surfaces for paint, etc. Of course, some projects required total sandblasting and framing-off (I will probably start a new thread soon showcasing another Cadillac in my collection), but with this very case we should be very gentle. Remember that sandblasting and ortho is not the panacea, and here it would have negative long-lasting effect.





Covering every piece that can be harmed by the red oxide primer dips



This is what was chosen as the best fit-for-purpose in the current case. Next, I'll paint the frame with black Rust-Oleum Hammered Enamel for rusted surfaces. I applied two layers with a 2-inch roller, and in hard-to-reach areas, I used a 1-inch long-bristle brush.



The frame has been painted (I'm not showing the results to keep the suspense), and everything has been wrapped in protective film. Next, I'll paint the underbody with red-brown primer with Rust-Oleum corrosion inhibitors.



Everything that could be dripped on with paint is being protected. I'll apply the paint using both a roller and a brush for even coverage and deep penetration. Between coats, I'll sand with 240-grit sandpaper.



Here's the view after applying the first coat. You can see a bit of the frame after painting here.



The insert that distinguishes the 60 series from the 62 series (the 62 doesn't have this). This is how much longer the Fleetwood's wheelbase is compared to the sedan or convertible.







Visible streaks are from the factory primer, as the bodies were primed by immersion in a bath.







The second heater and hoses for it.


Meanwhile, I had to prepare a ton of other things for installing the exhaust.



I ordered hangers to create ones as close as possible to the originals. I decided not to use the universal hangers that came with the exhaust. Also, new bushings for the rear shock absorbers.



These stainless bolts are for mounting the hangers instead of the original rivets with rounded heads.



A sleeve for the downpipes. It withstands temperatures up to 2000°F, with stainless steel clamps for securing it.



It will look something like this. Originally, the downpipes were wrapped in asbestos-containing material and clamped with some infernal clamps. After weighing all the pros and cons, I made the executive decision to do it nicely and more efficiently.



These hangers will be disassembled; I only need the rubber from them.



... and this rubber will be used instead of trunk straps on the original hangers, which still need some work.



The hangers were aggressively welded instead of being held by clamps.



And the last photo for today: the old exhaust logically goes into the trash bin

Lastly, these photos are taken after the 1-st coat applied. Then it will be sanded and primed again, covering what was not covered at the first time, and giving the flat uniform surface.

[Roger Zimmermann]

As you closed the canal for the carb pre-heating, you don't need the heat riser. Maybe you will need a spacer for the exhaust geometry.

[James Landi]

"This is the so-called "Heat Riser," which originally had a valve that directed gases from the left manifold to the right through a channel in the intake manifold to heat the carburetor. As the engine warmed up, the bimetallic spring straightened, and the valve fully opened, redirecting gases from the left cylinder head to the left exhaust tract. This system isn't necessarily unreliable, but for Texas, it's even harmful. A new Heat Riser for a 1953 Cadillac costs around $500. And, yes, the gas is different today and needs much less heat to evaporate..."

I (painfujlly) recall having exhaust valves burn and fail way back in the late 1960's, probably due to a partially opened but thoroughly frozen heat riser flapper . Even though that car received regular maintenance, no one ever seemed inclined to check mine for operation.  Was this device limited to Cadillacs and therefore a rarity?

[kudims]

"This is the so-called "Heat Riser," which originally had a valve that directed gases from the left manifold to the right through a channel in the intake manifold to heat the carburetor. As the engine warmed up, the bimetallic spring straightened, and the valve fully opened, redirecting gases from the left cylinder head to the left exhaust tract. This system isn't necessarily unreliable, but for Texas, it's even harmful. A new Heat Riser for a 1953 Cadillac costs around $500. And, yes, the gas is different today and needs much less heat to evaporate..."

I (painfujlly) recall having exhaust valves burn and fail way back in the late 1960's, probably due to a partially opened but thoroughly frozen heat riser flapper . Even though that car received regular maintenance, no one ever seemed inclined to check mine for operation.  Was this device limited to Cadillacs and therefore a rarity?

Many cars have it. Design is different, but idea is similar: guide hot exhaust gases towards the intake to heat the carb while engine is not hot enough

[kudims]

New exhaust, Part 3

Well, let's continue—or rather, finish up today with the exhaust system.

The photos and captions speak for themselves. No introduction needed.



Exhaust muffler mounts. Photos of the rusty ones were in the previous report. These have already been sandblasted and painted.



New rubber mounts and support washers for the shock absorber rods. The shock absorbers themselves have been cleaned to a shiny original bronze finish.



Last time there were photos of the undercarriage in primer. At the Fisher Body factory, body painting included spraying over the primer. I tried to replicate this to the best of my ability, it turned out moderately spooky, which kinda emphasizes the imitation of originality.



The spray was directed precisely according to how the painter held the gun.



Preparation of mounts. I applied red thread sealant to make sure it definitely wouldn't come loose.



Instead of a heat riser, there will be a spacer made of two stainless steel flanges. The height of the spacer is exactly what I need. Without the spacer pipes won't set up.



Fastening the downpipes in stockings.



Sealing the flanges with high-temperature sealant.



The left downpipe is ready.



The right pipe is also ready.



New special bolts for mounting the air conditioner evaporator to replace the slightly rusted originals.



The only part of the entire exhaust made of regular steel are two flanges for attaching the intake pipes. Everything else, including clamps and mounts, is stainless steel.



The right intake pipe is also in place.



Assembling the exhaust is a separate LEGO game, considering the complex shape of the pipes and the route, which is not straight at all.



Driver's side. Fuel lines, frame.





Heater hoses over the left muffler.



Who would say the body wasn't removed from the frame? ;-)



Central tunnel and propeller shaft



Left muffler mounts



Again, left side. Body mounts were kept original, as they are in great shape. I personally don't believe that the new body mounts will look the same after 70+ years of service.



Supplementary electrical GM pump. Huh, I see that I forgot to install new rubber body plug ))))



Left parking brake cable and resonator



Right muffler and hangers



Copper air conditioning lines were cleaned of oxidation with 800, 1200, 2000 grit sandpapers with water.



Air conditioning pipes. Under the filter-drier, the factory frame marking with white paint is preserved. There, in particular, is the manufacturing date. I decided to leave this spot untouched. Especially since it's well preserved, protected by the filter.



New rubber on an aluminum clamp, new original screw, and special crown nut washer. All for the sake of Feng Shui.



Right muffler. Connection with the downpipe.



Left downpipe and left muffler.





A/C copper pipes shine like on a battleship



Mounting the air conditioner evaporator and the right drainage hole.





Resonator mounts.





Right bumper outlet. Aftermarket exhaust tips were renovated to some extent, nevertheless, new ones are needed. I am going to send rear bumper and few other pieces of trim for re-chroming soon. With those tips... The price $800 and more, which people ask for those pieces of steel (even not stainless) is not fair. Now I have several opportunities to launch its fabrication. The only thing that really stops me is how many of them to produce. There should be a balance between number of produced and the final price. For instance, production batch of 500 will give final price $100, but how long will it take to sell them? Or, production batch of 200 will result in final price $200, but will be sold immediately



Left bumper outlet. The crossbeam between the frame and the wing was brutally perforated by welding. This happened during an exhaust upgrade when the pipe ends were equipped with elbows for gas exit past the bumper. Naturally, all this will be removed when the bumper is re-chromed.



The left exhaust pipe passes within millimeters of the fuel tank neck, and that's how it's supposed to be by the factory.



Original leaf spring insulators



I think that I need to make better looking photos from the car lifter. Should I?

[kudims]

As you closed the canal for the carb pre-heating, you don't need the heat riser. Maybe you will need a spacer for the exhaust geometry.

Roger, thank you for the comment.

Those passages through the carb throttle plate were clogged by some unknown high-temp resistance substance long ago, so I just made it more fancy with locking bolts.

The intake now acts as if the engine is hot from the very beginning. Nevertheless, when the engine is on, there are some gases travelling inside the intake, as I monitor higher temperature locally over the passage.

And the spacer, yes, of course - to keep the correct layout.

[Roger Zimmermann]

Olson's Gaskets is selling a gasket set for the intake manifold which has the cross-over holes blocked. This prevents the manifold to be heated. 

[cadman59]

Olson's Gaskets is selling a gasket set for the intake manifold which has the cross-over holes blocked. This prevents the manifold to be heated. 

But as far as I understand, it also prevents the original choke from working correctly because the choke tube nog longer gets heated. Correct me if I'm wrong.

[kudims]

Olson's Gaskets is selling a gasket set for the intake manifold which has the cross-over holes blocked. This prevents the manifold to be heated. 

Not sure that this is the best solution ever. The manifold must be heated, as otherwise it will be cooled by the gas mix vapor, and the engine will not work as intended. Me, living in South Texas with summer temperatures ~100F, never had issues with overheating the intake. But at the same time, when we were driving high mountains in Wyoming with snow in June and temperatures ~32F, we also never had issues with cooling down of the intake