I am trying to get the timing and carb adjusted on my 54 239 ohv. There is only one mark on the damper and I was wondering if that's the only mark you line up the pointer on when you put the timing light on it. Also I noticed no matter how I move dist when running when I give it gas it hesitates real bad at first then levels out. Also when I pull the vac line off the back off carb to plug to set timing I feel no suction at all from the hose.

 

There is almost no vacuum in that line at idle. It's not manifold vacuum.

If the early Y-blocks are like flatheads, ye, you just line up the bump on the crank pulley with the pointer.

Have you watched the timing when you blip the throttle? The timing should advance.

 

Theoretically engine timing could be set at idle spec without disconnecting/plugging vacuum advance hose. It's kind of a "belt and suspenders" thing. It simply removes any possible variables from the equation, such as a vac hose hooked to the manifold port, or idle set too high, etc.

You can observe the limits of mechanical advance with a light at 2500 RPM say, then reconnect vac hose and see how much additional timing the vacuum advance brings in on top of that.

Set idle to specified RPM. Put the timing light away for now. Then set timing with a vacuum gauge - usually about 1" of vacuum below the max manifold reading is pretty close to perfect. Set idle to spec again. Set idle mixture, and finally, reset idle. Check for ping or detonation on highway and acceleration, back off a little more if necessary. This works slick.

 

That won't work with a Load-A-Matic, it's 100% vacuum-controlled advance.

 

Yeah I knew that. Always paired with the teapot carb?

 

Unless someone changed it, it's a Holley 2110. Merc flatheads were the only engines that used the teapots.