1973 Will Not Start

BowlingSS

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I just finished my third engine build this year. The 72 and 81 started right up on first try. But my 73 does not want to start. It does pop thru the right exhaust a couple of times.
I replaced the wiring harness, battery, rings, gaskets, seals, points, condenser, plugs, coils, coil wires and caps. I also cleaned both carbs and of course did a value job.
I did the following with the engine installed:
1) Set the valves
2) Set the timing
3) Cleaned the carbs again, diaphragms are good.
I am getting spark. The plugs do not seem to be wet.
Is it possible that I got the valve timing off? That has never happen to me because I am usually so careful, but I am getting older.
I might try to take the carbs off my 72 and try that.
Is there anyway with the engine installed to check the valve timing?
Thanks.
 
The pin on the right side of the cam that holds the advance in place should point straight up or straight down with the rotor set to TDC. Did you try swapping the plug leads? It's possible to get the ignition 180° out.
 
Swapping the plugs wires did the trick. Thanks Jim. I just swapped the coil wires. They must have been wrong to start with. This was a basket case. Engine sounds great. Now for a test ride. It is very cold today.
 
Finding Ether is getting tough. Starting fluid can be gotten a lot of places. That's got some ether in it but not straight. Even at that you need to be careful with it.
If I want to do something along thoise lines I put gas in a trigger pump oil can. Squirt a pump or two down each plug hole.
From the results you are getting it sounds like the timing is 180* out. Swapping the plug wires will correct this for testing. If it runs, then you can figure out why it's out. Often the pins on the advance rod get assembled wrong. With the rod out. Both pins should be on the same side of the rod.
Leo
 
Finding Ether is getting tough. Starting fluid can be gotten a lot of places. That's got some ether in it but not straight. Even at that you need to be careful with it.
If I want to do something along thoise lines I put gas in a trigger pump oil can. Squirt a pump or two down each plug hole.
From the results you are getting it sounds like the timing is 180* out. Swapping the plug wires will correct this for testing. If it runs, then you can figure out why it's out. Often the pins on the advance rod get assembled wrong. With the rod out. Both pins should be on the same side of the rod.
Leo
I did check the pins. They are OK.
 
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Another thing that often happens is the wire running from the coil to the points gets swapped around, so the right points fire the left coil. Then the left fires the right.
Try swapping the plug wires.
Leo
 
To avoid confusion in the future, check to see that you have the right color wires running to the correct points sets. The upper points set for the right cylinder should have the gray wire run to it, bottom set for the left cylinder should have the orange wire .....

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Up at the spot where the condensers tie in, the orange points wire will connect to the double bullet on the orange wire. The other end of that orange wire will connect to the left coil. Gray points wire connects to gray wire double bullet and on to the right coil .....

kdvXTdb.jpg
 
The new coils have a black and yellow on both coils. I set it up using the old coils. My old coils are probably good but could be almost 50 years old.
 
Now my other problem is the starter just spins part of the time. Is the cause the spring near the clutch?
 
Yes probably. The drag clip on the #4 starter gear is probably spread open too much. It's supposed to drag on the gear and slow down it's rotation. If it doesn't, the gear has trouble engaging.
 
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