Dialing In Motor

Thanks for the info.  I'll search out a vacuum gauge and go through the steps recommended in the link.

I found an old vacuum pump with a gauge.  Where is the best place to hook it up?

I have the vacuum assist windshield wiper motor set-up in the location specified, as well as a tach/dwell light.  Before I shell out money on a vacuum gauge, would a carb down-draft gauge be suitable? I have two which I use to balance the carbs on my Pinz.

Vacuum gauge procured and everything else in place.  Here are the results of the carb/timing adjustment.  Mixture screw turned out two turns and idle screw turned in three turns prior to start of adjustment.  Plugs clean and gapped, and valves adjusted.  Oil and coolant okay.  Ambient temperature approximately 44 degrees F.  Got the motor up to operating temp and adjusted distributor instructed.  Vacuum after dropping RPM stayed at 15"-16" Hg.  Adjusted idle screw to maintain vacuum at 15" Hg, which resulted in an idle of around 1100 RPM.  Any slower and the vacuum dropped and became erratic.  Screw in the mixture screw in 1/8 turn increments.  When the mixture screw got to 1 1/2 turns from bottom the engine RPM dropped and died.  It would restart with a pump of the gas, but died again until I returned the mixture screw to two turns out.  The best I could achieve is 1 7/8 turns out.  At this point it would idle smoothly at 1000 RPM and maintain a steady 15" Hg vacuum. 

I repeated the procedure about three times with the same result: smooth 1000 RPM idle, steady 15" Hg vacuum, good throttle response, stopped without knocking or run-on, and easily re-started.  I was unclear on one point: when reducing the idle at the distributor, do you turn the distributor clockwise or counterclockwise?  What advice do you have to get the idle to a respectable 700 RPM? 

On a side note, I discovered that my flywheel is 180 degrees out of alignment.  I set the timing light to two stroke and advanced the light to 95 degrees, and there was the timing mark.  

Thanks,

The motor is original as far as I know.  I'll try a cylinder leak down test and see what happens.

Here are the results form the latest round of tests:

Dry Compression Test
Cylinder #1: 96    
Cylinder #2: 95
Cylinder #3: 96
Cylinder #4: 100

Wet Compression Test
Cylinder #1: 96
Cylinder #2: 96
Cylinder #3: 100
Cylinder #4: 106

I conducted each test twice for each cylinder, and the results were +/-3%.  I tried the leak down test but on each cylinder the motor kept trying to spin, despite removing all of the spark plugs.  The best I could do was to brace the breaker bar and move it slightly clockwise to keep the valves closed.  In this way I could get a reasonable leak reading, which roughly ran 5% to 10%, and I could detect a little air escaping from the carb or oil filler hole depending on how well I was able to keep the breaker bar immobilized, which was a struggle.  I've done this test on other motors but didn't have this happen. 

I discovered that the #3 plug was a little loose and had some carbon on it.  After I reassembled everything I covered the instructions once more, and was only able to get the idle to remain steady at 950 RPM.  I removed the air cleaner elbow from the carb and shot the strobe down it, and saw a lot of liquid fuel droplets in the bore as the motor ran.  I leaned out the carb while watching the stream but was not able to get it to change from drops to mist before the motor died.