1950s 1959 Cadillac fuel starvation issue.

[Eric DeVirgilis CLC# 8621]

Thanks but the carburetor is a Rochester.

I had just run the engine for over an hour (parked)  periodically applying/holding the accelerator to simulate driving. It became good and hot with the temp gauge rising to the halfway mark. Too hot to even touch the front crossmember above the grille. No bubbles in the glass and did not stall.

Then I decided to put the trans in gear and the idle got progressively rougher until it eventually stalled. But this time, the engine fired right back up again - several times. It's maddening.

I wonder if something isn't goofy in the carburetor which was rebuilt late fall/early winter but never drove the car until now which is when all this began.

[Jon S]

Sounds like the engine is idling too slow if putting it in Drive stalls it. Adjust the idle to 550/600 RPM AND open the air horn screw on the back of the carburetor 1/2 turn.

[dn010]

What kind of gas / how old, are you using? Last tune-up date?

[Michael Petti]

I am late to this too. Your first post said you put on a new fuel pump, and it ran for a while but developed the same thing again. The replacement pumps available are notorious for poor quality and early failure. This forum has more than a few posts on this
I went through 4 in 2 seasons.  One was bad right out of the box. Check the pump pressure and or volume. The fuel filter could be clogged too. My solution was to have AG Rebuilders rebuild an original AC pump core. Keep us posted.

[James Landi]

Hi Eric.
Sometimes the float gets stuck and won't release until the engine is cold and some gas in the carburetor evaporates through the opening vents on the carb. Next time you go driving, take a 🔨 with you, and when the engine starves for gas, give that Rochester a good clunk or two near the gas inlet on the carburetor. I've experienced this issue both for fuel starvation and flooding...the hammer got me home. Any misalignment of the float or a ridge line on the needle can cause this problem.

[Eric DeVirgilis CLC# 8621]

The engine runs now so I doubt the pump is the problem. When a pump goes bad, it usually stays bad.