Question Rebuilt 1958 223 cid. Timing set right, lash set right, new points plug and condenser. Will Has original Holly 1 brl carb. When running (even after reaching operating temp) still will only run with full choke. When accelerate bogs down and backfires thru carb. Checked but found no manifold leak.
Answer If the engine will only run with the choke out there is either a humungus vacuum leak or a carburetor/fuel flow problem. First check the fuel pressure. It should be about 4PSI when tested with the engine cranking. Then connect a piece of rubber fuel hose to the fuel line and then using a peanut butter jar or similar plastic jar crank the engine and check the fuel volume. You should get a pint of fuel in less than 30 seconds. If either of these test fails the problem is in the fuel pump, fuel filter, fuel line, of the pick up screen in the tank. If the fuel flow and pressure is OK then the problem is the carburetor or vacuum leak. Oh, one last thing. Does the car have power brakes? If so a leak in the vacuum brake booster can cause a big vacuum leak.
Knowledgeability = 10
Clarity of Response = 10
Politeness = 10
Clear, concise instructions to diagnosis the problem. Thank you. It is a all original 1958 F100 restoration project for my 17 year old son.
All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.
Automotive tech instructor.
Syndicated auto columnist 1970's though the early 1990's.
Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's
TV Show "Last Chance Garage" 1980's PBS-TV syndicated.
Auto instructor for the following companies:
University Of Conn
Blue Hills Technical School
Sugar River Technical Center
Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.
Publications Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.
Education/Credentials More than I care to remember.
Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.
Awards and Honors Moto Award winner. And much more.