vapor lock
- Thread starter fogfrank
- Start date
its not just A MERC PROBLEM, ALL CARS ARE VUNERABLE TO THAT PROPLEM, IT HAPPENS WHEN THE FUEL IN THE FUEL LINE GETS HOT ENOUGH TO BOIL AND VAPORIZE THE FUEL IN THE LINE, CAUSED BY THE FUEL LINE BEING TO CLOSE TO THE EXHAUST PIPE OR EXHAUST MANIFOLD, fuel pumps wont pump vapors, so the carb runs out of fuel, it happens on real hot days mostly, try relocating the fuel line or insulating it
cuzncletus
Senior Member
Don't leave out ethanol. My Model A buddy was vapor locking every time he turned the car off for a short period of time. Simply switching to non-ethanol cured it.
rotorwrench
Well-known member
Winter season fuels are formulated to take advantage of the lower vapor pressures needed in cold weather. This also saves the distributors some money since this fuel is less expensive to blend. If you have winter fuel in the tank when it gets warm, it can vapor lock easily.
In all the years that my hand me down 1951 Merc has been around, I don't remember having any specific problems with vapor lock. I have had various problems with fuel delivery though but most of those were due to crud in the fuel lines or carburetor bowls and bad fuel pumps. The Holley 885 can experience internal leaks & plugged passages some times that can be repaired by a good rebuild.
In all the years that my hand me down 1951 Merc has been around, I don't remember having any specific problems with vapor lock. I have had various problems with fuel delivery though but most of those were due to crud in the fuel lines or carburetor bowls and bad fuel pumps. The Holley 885 can experience internal leaks & plugged passages some times that can be repaired by a good rebuild.