Misses and pops

B

bob p

Well-known member
I have a 1931 Model A that I just bought recently. On the first try to start it it missed and popped. I replaced the points, condenser, then the dist. coil, dist. body, cap, wire and rotor, manifolds carburator and checked the timing gears. the valves all work and have 65 lbs. comp. New gas. Ignition switch and cable. I am stumped. It has always seemed to me to be out of time. Any suggestions. Thanks, Bob.
 
If you have a Model B timing cover on a Model A it will look fine BUT the timing will always be way off. See below...........

Here's is a great link to Timing Covers.

http://www.fordgarage.com/pages/timingcovers.htm

READ TO THE END. THE FINAL CONSIDERATIONS ARE EXTREMELY INTERESTING AND MAY BE YOUR ENTIRE PROBLEM...IF IN FACT YOU CAN'T SEEM TO TIME THIS. Again I need others here to tell the difference from a Model B distributor and a Model A distributor.
 
I assume you mean popping in the carburetor. Missing and popping from the carburetor are a sign of a lean mixture. You can verify this by opening up the GAV quite a bit or holding the choke partly closed. If the engine runs smooth under either of these temporary fixes then it is likely that there is crap in the carburetor and it needs to be cleaned out.
 
Pops was what my dad called his dad. When referring to my grandparents I guess I could call them Misses and Pops. They died a long time ago but these days I see my grandfather in the mirror.
 
The FIRST thing to do is to try and determine if its a fuel or a spark issue. Obviously timing needs to be set correctly too. To check ballpark timing find top dead center compression stroke of first cylinder, then mark the front pulley with a bright paintstick. Now lift the first cylinder spark plug strap a 1/4" off of the lug. Have someone turn the car over with ignition on, keep gas off so it doesn't start. You should be able to see the spark jump the gap at the same time the mark on the pulley comes around. (or you can use an old timing light) Like I said, its ballpark only. If that checks OK, lift all of the sparkplug straps a 1/4", start the car and watch the spark jump the gap, you'll be able to see if its a nice strong, blue, regular spark or if its yellow, weak, and intermittent. If all that checks out then turn to the carb/intake manifold/etc. Its NOT a good idea to start replacing parts until you determine what is wrong. Shotgunning, or throwing parts usually introduces more problems than it solves. Usually if a piece of equipment has 1 problem, its typically pretty straightforward to solve. If there are two separate problems its about 4 times as difficult to solve. 3 problems and its at least 9 times as difficult. That's my math, not scientific :)
 
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eagle said:
The FIRST thing to do is to try and determine if its a fuel or a spark issue. Obviously timing needs to be set correctly too. To check ballpark timing find top dead center compression stroke of first cylinder, then mark the front pulley with a bright paintstick. Now lift the first cylinder spark plug strap a 1/4" off of the lug. Have someone turn the car over with ignition on, keep gas off so it doesn't start. You should be able to see the spark jump the gap at the same time the mark on the pulley comes around. (or you can use an old timing light) Like I said, its ballpark only. If that checks OK, lift all of the sparkplug straps a 1/4", start the car and watch the spark jump the gap, you'll be able to see if its a nice strong, blue, regular spark or if its yellow, weak, and intermittent. If all that checks out then turn to the carb/intake manifold/etc. Its NOT a good idea to start replacing parts until you determine what is wrong. Shotgunning, or throwing parts usually introduces more problems than it solves. Usually if a piece of equipment has 1 problem, its typically pretty straightforward to solve. If there are two separate problems its about 4 times as difficult to solve. 3 problems and its at least 9 times as difficult. That's my math, not scientific :)
Click to expand...
I concur.
 
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