I cannot keep my 1957 Cadillac Biarritz running

[V63]

A concern with using 'low grade' low octane fuel we are forced to use today is with the high compression engine of a 1957 Cadillac. It will have detonation issues, pinging. The easiest (not the best!!!) common 'fix' is to retard the timing which increases engine temperature. You may find your timing is retarded from factory recommendation.

I never realized the benefits of LEAD but now that it is absent from pump fuel, and you run engines such as these on the proper octane with LEAD, WOW the results are absolutely amazing. There is a new found smoothness and quietness. Nothing short of amazing. Also I notice the improvements are not limited to high compression engines, even a lawn mower runs so much better that was designed to run on low grade fuels. (I am speaking of authentic lead additive NOT marketing substitutes)

Your 57 Cadillac uses HOT exhaust to heat directly under the carburetor(s) you will notice the paint is burned off the center of the intake manifold. If your use of the car will not be in sub zero temperatures I suggest BLOCKING those passages because that added heat combined with alcohol blended fuels is a source of many drivability issues. The least of which the excessive heat can boil the fuel out of the carburetor bowls so your next start is labored having to refill them first.

Engine vacuum is very important, you must verify it is sound, verify the distributor vacuum advance circuit and device is sound. I would temporarily disconnect and eliminate the vacuum wipers (as if they work🤦🏻�♂️) until you get the engine sorted.

 

[Lexi]

I never realized the benefits of LEAD but now that it is absent from pump fuel, and you run engines such as these on the proper octane with LEAD, WOW the results are absolutely amazing. There is a new found smoothness and quietness. Nothing short of amazing. Also I notice the improvements are not limited to high compression engines, even a lawn mower runs so much better that was designed to run on low grade fuels. (I am speaking of authentic lead additive NOT marketing substitutes)
 

I sometimes add "lead substitute" to Lexi and I always note that the engine runs more quietly and smoother. Enough to take notice of. Same, prior to engine rebuild. Like what V63 noted, with respect to quietness. Unlike the old lead additives that were available, I am sure these new ones do not contain lead, but in my opinion they still seem to do the job as based on how quiet the engine sounds once added. Whatever is in there must provide some extra "cushion" so when the valves open and close noise is reduced. Can't be a bad thing (I hope), but it certainly adds to the cost of a fill up. Any comments? Could whatever is in these new lead substitue additives over time cause another problem? Clay/Lexi

[Daryl Chesterman]

If it is a vapor lock issue, the exhaust heat riser (if your car has one) being stuck in the closed position will definitely cause increased heat under the carburetors causing the fuel in the float bowls to boil (vaporize) and cause vapor lock.  The suggestion to block off the exhaust crossover on the intake manifold is also a good idea to reduce the heat under the carburetors.  If you are using ethanol gas, I would suggest using a tank of nonethanol gas and see if that takes care of the problem. 

Daryl Chesterman

[Gabe Davis]

Unlike the old lead additives that were available, I am sure these new ones do not contain lead, but in my opinion they still seem to do the job as based on how quiet the engine sounds once added.

Looks like the VP Fuels Maddative Octanium (the one in the purple can) has Tetraethyl Lead in it according to the safety data sheet.

https://drive.google.com/file/d/1Fu4BbTaPOYJJ5k68jpR388lpcLAwQxYB/view

https://vpracingfuels.com/product/octane-booster-vp-octanium/?c=367&;

For "off road" use only. But as you describe, using that additive makes the car idle much more smoothly and seems to run better overall. Using that with non-ethanol gas has helped avoid vapor lock too.

[Lexi]

Gabe thanks. Must check those products out! Clay/Lexi

[Michael Petti]

Have you checked the manifold heat regulator? If that is stuck or rusted closed it can cause the carb and manifold to overheat and boil the gas in the carb causing fuel starvation.Just a thought.

[Chopper1942]

If you suspect a vapor lock issue, shielding the fuel line can eliminate the issue.  To check the integrity of the fuel lines, remove the fuel inlet at the fuel pump, start the engine, and check the vacuum. It should be 15-18 in.hg.  Now remove the fuel line at the fuel tank and connect the vacuum gauge to the fuel line and start the engine. It should read the same and when you shut the engine off, it should hold the vacuum.  If it doesn't, you have a leak in the fuel line.

[Rogerscadillac]

https://share.icloud.com/photos/00aGHB0zxSziegIyyoht3Ptkw

Good  day everyone: I love all the post- Thank you😎.  Today took the 1958 Facel
Vega to my first coffee and cars.  Came home and started on the Cadi- We put Marine stabilizer in the fuel tank. Took it for a 35 minute spin around the neighborhood and she ran great.  I was so excited - My dad would be so proud!!
We fixed the problem.  Got out lifted the hood and no fuel ever reached the glass bowl (fuel is vaporizing before it reaches the glass bowl).  I was like "no-no come back", and Yeap she stalled.   Next step this week is to get the gas out of the tank and replace it with lead gas.  Maybe put a riser on the carburetor to reduce the heat, not sure just trying little easy steps first. Before the big expense. Will keep you updated. Hopefully the video uploads of the engine and fuel pump.  I also have to remember the cars were in Ohio and I live in Florida- temperature and humidity is different here.  Kindly, L.Plesz

[James Landi]

"...fuel started running out the glass bowl."   Are you referencing the glass bowl with a fuel filter?  If so, that's a dangerous leak in the gasket where the bowl seats, and has absolutely NOTHING to do with the type of gas you're using.  There should be no evidence of gas leaking outside of and / or on the engine or in the throat of the carburetor.  If gas is leaking out of the carburetor or down the throat of the carb, you likely have a bad float and/ or needle valve or the float is set too high and allowing too much gas to enter the carburetor.  Heat can exacerbate that problem, but no matter what FUEL you're using, NOTHING will cure  any of these leaking/ mechanical issues I've mentioned except a focused repair and remediation of what appears to be a reoccurring intermittent problem that is, potentially, serious fire hazard.  Hope this helps you, and I mentioned the fire hazard out of concern for you and your property... it's NOT the gas you're using, if gas is leaking out of components that are engineered not to lea, they find a competent mechanic who can fix the leaking gas .    Respectfully,  James

[Chopper1942]

Since you live in Florida, I would install metal shims between the intake manifold and cyl heads. This will block the exhaust from heating the fuel in the carb.  Tie the heat riser open.  This will improve driveability when warm, but may want to be a little cold blooded when first started.

[Rogerscadillac]

Good Day Everyone
 I wanted to follow up on the original post and everyone's help. This has been quite a journey. I did not get back to the Cadi as planned, I took the 1958 Facel Vega to my first car show at the Elliot Museum in Stuart Fla.   Upon parking, pulled the hood latch and "Bam" the release broke. Not only that, I kept hearing a clicking sound near the rear driver tire. I knew this was not normal.  After investigating, the exhaust pipe had come loose from the strap and was leaning against the tire. Now that both are fix, my husband and I started investigating the Cadillac vapor lock.  I am embarrassed to say, we totally missed a second fuel pump installed under the car and the switch is in the glove box.  Flipped the switch and the car ran for 50 minutes down the road without a vapor lock. The lessons learned on my classic cars will be many, and I thank all of you for helping us think. 

[Chopper1942]

First thing. ABSOLUTELY DO NOT USE ETHER STARTING FLUID TO TRY TO START THE ENGINE!!. Ether is a good way to et a new flywheel and/or starter. I have seen this many time here in Iowa when someone tried to start their car in the winter and it backfires. Have also seen when they would not start and let sit for a while, then tried to start it, blow the valve covers, valley cover, and oil pan off. The oil pan bolts were still in the block.

That said, either use choke cleaner or better yet use mass air flow cleaner. If you have an oil bath air cleaner remove it. If I remember correctly, i'm not sure about the Caddy dual four set up, but on Chevrolet, the rear carb is the primary carb. Open the choke blade, spray the cleaner into the carb throat while cranking the engine.

Check the heat riser and make sure that it is not stuck shut.

As suggested, cleaning the fuel tank, make sure that the fuel tank can vent (has the gas cap been replace with non-vented cap), and new rubber fuel lines is always a good idea for older vehicles. Make sure that none of the fuel lines run close to the exhaust.

In the past couple of months there have been several post and replies about over heating issues and fuel system issues.

Just don't throw parts at it. If you need help trouble shooting, just ask. We will be more than happy to help you.

To start, I would recommend getting a infra-red digital temperture gun and measure the thermostat housing, upper radiator, and lower radiator hoses. If you can, measure the temps at the back of the cylinder heads and the intake manifold exhaust crossover.  This will help diag the heating issue.

I would start here and then address the engine not running issue.

[jwwseville60]

All of the above and add an electric fuel pump on a switch, return line and a visible fuel filter.