VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 1954 235 chevy engine

ugh. help. I have a 1948 dually flat bed with a 1954 235 new in 2010. Hardly any miles and little driving since swap.
Just installed Petronix kit and coil, rebuilt Rochester 1b1 carb, new plugs and wires, new fuel pump (4.5 psi) She starts no problem. Idles around 700. She drove perfectly after engine swap.
Problem is she's got now power.
Also cannot find BB on fly wheel but playing with timing has no change in performance. I did check number one cylinder compression with rotor position.
I also removed the vacuum advance from carb to distributor.
Could the valves need adjusting.
I also checked compression on each cylinder. (i did not do by the book yet, but i will). I checked without removing all the plugs!
What am i missing? thanks for the wisdom in advance

Welcome. I'll move this to a technical forum for you to get you a wider audience.

You have made quite a few changes. Plus it sounds like the engine has set quite a while without running. That could be a factor.

You need to be organized and methodical in your troubleshoooting. For example, focus on either the fuel delivery or ignition until you have proven that one of those is operating correctly. Don’t bounce back and forth or you will ever be sure what is or is not working.

You need to check all the basics such as you noted the compression. Look at things like the firing order and find that BB so you can set the timing properly. Vacuum advance does not affect power. It only advances the timing under light load when engine vacuum is higher. Is the mechanical advance working correctly?

I am not a fan of the PerTronix conversion. I have heard enough stories of failures to make me suspicious of them. Plus you cannot set the timing unless the engine is running. You cannot set it statically like you can with points.

Also, if that engine is running correctly you should be able to make it idle smoothly at much lower than 700 rpm.

My thought some thing messed up in the carburetor or fuel delovery system or ignition system..............

Let me share a couple more thoughts. As Gene noted and as my Dad said his Dad always said “It’s either the spark or the gas.”

Hopefully an expert can jump in on this comment. The location of the timing mark on the flywheel could be dependent upon which flywheel and bell housing were used in your conversion. Is it possible that the flywheel was not indexed correctly when installed?

You did not indicate if you were still running a 6 volt system or had converted to 12 volts. That would be a factor in which PerTronix is required. The next point is whether PerTronix requires a special coil with their conversion. Typically 12 volt points ignition systems have a resistor in the primary circuit which reduces the voltage through the points and to t(phe coil to about 7 - 8 volts. Running 12 volts continuously through the regular coil could overheat it.

Compounding this is the rebuilt Rochester 1 barrel carburetor. What is the degree of confidence in the rebuild? I assume that it is a model B that is compatible with a ‘54 235.

Another item to check is fuel delivery. The fuel pump might produce 4 1/2 psi at no or low flow. Does the pump deliver enough flow when the engine demands more fuel at operating speeds?

Forget the timing light and rotate the distributor into different positions and see if it helps.
Install the original points and see if that helps.

You say no powre. Does that mean the engine shuts down or just will not go any faster.
Is the power piston in the carburetor stuck.

The engine may be new to you but it is impossible to be a "new engine".

On these stove bolt sixes the entire distributor turns when the vacuum advance pulls it,put the advance back on and check that.The ball is imbedded in the flywheel take the cover off and find it put a dab of white paint on the ball.