Q: 56 Mercury Custom w/ 312 V8 Y blk engine 4B carb, stalls whenever placed in D or R? New carb & distributor core; problem persists!

asked by on January 29, 2018

Have a 1956 Mercury Custom w/a 312 V8 Y Blk engine and 4B carb that stalls whenever placed in D or R. Problem started after overheating and being left stranded. Since then the heads have been done and all respective gasket replaced. 4B Holley has been replaced with a new Edelbrock 1403 w/elec choke. New distributor core, rotor cap and wires. Vacuum test on engine shows no leaks. Been advised that locking torque converter was a problem but only after the 80's, so it's been ruled out, yet problem persists and we can't figure it out. Any thoughts, recommendations? Seriously need help!

My car has 58000 miles.
My car has an automatic transmission.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Car parts that get damaged while driving through water
When you drive through water (https://www.yourmechanic.com/article/how-to-check-for-water-damage-in-a-used-car), the electronic parts should really never get wet because it can damage them. But, with that said, the electronic power-steering systems are sealed pretty well from water. They have got seals all over. Unless,...
I want to know if it's ok to drive to Canada from Massachusetts with bad converter
If you have a lack of power, it is not a good idea to put highway mileage (high RPMs) on your vehicle. It can clog your fuel injectors and damage your engine. There are two types of catalytic converter damage....
dust problem rear hatch
Hello. Thanks for writing in about your 2011 GMC Terrain. There may be a problem with the outside dust cover not sealing properly. This could cause dust to get inside the car. If the rear hatch isn’t sealing properly, this...
Weird noise in volvo 240
Without additional information it would be tough to say, however based on what you are describing, it sounds like potentially low differential oil causing the gears to whine a bit. There are also what is called trailing arm bushings (https://www.yourmechanic.com/services/trailing-arm-bushings-replacement)...
In 2nd gear, car feels like it might independently shift
Hi there, thanks for writing about your 2011 Audi S5. Your vehicle's transmission has 2 clutches that alternately engage and disengage, under computer software control, as the vehicle accelerates and decelerates. The software compensates for wear in most cases, but...
Good morning. My o2 sensor is out. I can't remember which one but when I schedule for someone to fix it, will they have the correc
Hi there. Did the gentleman at auto zone check for proper voltage going to the sensor? Proper return? Was a pin check performed at the engine computer to make sure that the computer was sending the signal? I would be...
The AWD disable light is on in my 2006 Buick Rendezvous
Some systems require more than a code reader to find a fault. The AWD disable light means that there is a fault with that system. The AWD system controls torque (rotational force) to the four wheels. This is to improve...
I have a 2005 trailblazer
Your vehicle can use up to 15% ethanol with no ill effects and such use (of E-15 for example) does NOT require regular use of any particular fuel system "cleaner". Most gasoline vended these days already contains a sufficient additive...
I have a Lexus CT200h dose the in tank fuel filter require replacing or is there an inline filter that is changed for servicing
Around the turn of the century manufacturers started using what we sometimes call "dead end" fuel systems. These systems put the pump, filter and pressure regulator inside the fuel tank eliminating the fuel return line. The fuel does not circulate...

Related articles

Symptoms of a Bad or Failing Air Pump Check Valve
A bad air pump check valve may create exhaust fume odor, fail your car's emissions tests, and turn on the Check Engine Light.
Mercury Certified Pre-Owned (CPO) Car Program
Drivers Drivers who are shopping around for a used Mercury vehicle may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on to...
Understanding the Mercury Intelligent Oil Life Monitor and Service Indicator Lights
Car symbols, or dashboard lights, are a car service reminder. The Mercury Intelligent Oil Life Monitor indicates when and what service your car needs.