24/25 t compression test

I ran the test with a regular compression gauge. I bought spark plug adapters for modern plugs from Snyders. The gauge must be for modern cars. They all were pretty close to 45 lbs.

The problem is the car will only run at one speed. If the throttle moves the engine dies. All of the plugs have spark but the exhaust is black. Moving the spark lever after starting makes the engine run a little better.

Do you think it is carburetor, timing or a combination of both?
 
What condition is the engine in rebuilt or good used?
Are you running a distributor or on coils with battery (lower top speed) or magneto (more varoom)?
If on coils, have they been properly checked?
If running a timer, which one and how is it set?
Are you pulling down the spark lever after you start?
Are you adjusting the needle valve after the motor warms up?
Are you opening the choke after you start?
Black smoke could be burning oil or running very rich.
With 45 LBS you should be in good shape.
 
The car sat for fifty years. I bought four rebuilt coils at the International Convention in Rapid this summer from a guy from Texas. The carburetor is a new one from Snyders and I adjust it after the engine warms up. The spark is advanced after starting. The coke is opened after starting. The smoke is not blue. The timer is a roller timer. I am running on the battery.

The gas tank, sediment bowl, carburetor, wiring, spark plugs, spark plug wires, fuel line, ignition switch, amp gauge are all new.

The new carburetor was rusty inside and I cleaned it with carburetor cleaner. I left the float set where it came from Snyders. The carburetor is new Holly.
 
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THE EXHAUST PIPE WAS INSTALLED THE OTHER DAY- NEW- ALONG WITH A NEW EXHAUST MANIFOLD. i DID NOT CHECK THE INTAKE MANIFOLD FOR FOR A PLUG. THE OLD CARB WAS ON THE ENGINE AND THE THROTTLE WAS CLOSED. THE OLD CARB WAS A RUST BUCKET. THE FUEL BOWL WAS ALMOST RUSTED OFF.


IS THERE AN EASY WAY TO CHECK THE INTAKE WITHOUT REMOVING IT FROM THE ENGINE? I AM RUNNING OUT OF GASKETS.

I APPRECIATE YOUR RESPONSES.

THANKS
 
Try coating the area around the intake to block joint with grease, it will form a temporary seal if there is a leak. If that is the case there should be a noticable difference - for a short time. I assume you are using the original style copper rings & steel glands. The flat gaskets are not very reliable.

Even though the fuel system is all new it might be wise to open the carb. drain or take the fuel line off at the carb. & be sure there is a good fuel flow.
 
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The only way I can think of for checking the intake without removal is with air pressure. With choke and throttle open you'll have to hand crank a cylinder to intake, when the int. valve is open and blow back from the spark plug hole out thru the carb. I feel the black smoke is an over rich mixture. That carb doesn't sound too hot either. (rusty). Pretty sure from the text that it's a fuel problem. Sounds like the spark is at least present. That quitting on opening the throttle has me stumped. It sounds like a vaccum leak.
 
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