wont fire

F

f balsiger

Member
after 20 years storage. I started this model a and it ran rough (mising,back fires) changed distributor because plastic on the old points failed.
timed with the front pin.
have compression, stong spark at plugs, plenty of fuel in the carb. ( I can overchoke it and gas runs out the throat)
It wont even fart. ANY THOUGHTS??
 
Is It timed correctly ? I think that is the big question. Rotor end should be just to the right of the #1 distributor cap post when engine is at TDC on compression stroke.

Does it have compression ? Add a bit of oil to each cylinder.
 
Check anything you changed. Most likely you have created your own problem.

Did you change the oil? Put some MMO in the cylinders to help the valves. Check you carb, jets. Wiring to.

We have a Model A that sat from the end of WWII until 1981. Started right up and is still running great today. Just take your time and please don’t start taking things apart.

It will run again.
 
Patrick L. said:
Is It timed correctly ? I think that is the big question. Rotor end should be just to the right of the #1 distributor cap post when engine is at TDC on compression stroke.

Does it have compression ? Add a bit of oil to each cylinder.
Click to expand...

50 pounds in every cylinder
 
Add your location to your profile. There may be an "A" owner nearby to walk through this with you. Chap
 
You have compression, good spark and good fuel.

Add a little oil to each cylinder, spin it over, set timing correctly, install sparklers. Start it.
 
This is what you should see if your timing is correct.


44388543034_439f2299dc_z.jpg



The advance/retard lever to the left of the steering wheel needs to be at the top of its range. The timing pin must be in the dimple of the timing gear.

You should use the hand crank or be moving the car forward, with the transmission in 3rd gear, when the pin moves to the bottom of the dimple. This will have all the gear lash removed from your setting of the rotor.
 
Patrick L. said:
There ya go ! I can't figure out how to post those pictures. Computers drive me nutz.
Click to expand...


I believe this picture originated from Tom Wesenberg, but I copied (control/c) it from a thread on this forum called "Rotor Position Question" and pasted it into the post.
 
Rob Doe said:
I believe this picture originated from Tom Wesenberg, but I copied (control/c) it from a thread on this forum called "Rotor Position Question" and pasted it into the post.
Click to expand...





Yep, I believe so. I can find them, just can't figure out how to post them. A pic sure beats trying to describe it.
 
Yes, the rotor has to be near the pin for the cylinder #1, but more important is that the points are just opening. Clean the points with 400 grit went and dry paper. Fold the paper over so that you clean both points at the same time. Clean any grit out with a piece of thin cardboard. Adjust the points to 0.020 inch with the cam at a position where the points are open the greatest amount. Turn the engine over by hand so that the timing pin drops into the detent in the cam gear. Push the advance lever all the way up, fully retarded. Use a trouble light or multi meter in the ohm position, with the ignition off, and see if the points are closed when you turn the rotor by hand clockwise and open if you turn it counter clockwise. If not adjust the cam position until this is the case. Put the cardboard back in the points and with the ignition on measure the voltage at the moving point. It should be the same as the battery. Turn the ignition off. Take the cardboard out and turn the engine over until the points are closed. Turn the ignition back on. Now measure the voltage again at the moving point. It should be very close to zero. If you do not measure the voltages as described you have an open circuit, a short, or the points are not conducting. Find out why and fix the problem. This should take no more than half an hour or an hour at the most if you have to fix something. Don't leave the ignition on for more than about 30 seconds with the points closed.
 
Last edited:
f balsiger said:
after 20 years storage. I started this model a and it ran rough (mising,back fires) changed distributor because plastic on the old points failed.
timed with the front pin.
have compression, stong spark at plugs, plenty of fuel in the carb. ( I can overchoke it and gas runs out the throat)
It wont even fart. ANY THOUGHTS??
Click to expand...
is the timing dimple also the recess for the timing pin?
 
Yes. The pin will pop into the dimple (dent) in the timing gear when the number 1 piston is at top dead center (TDC). Turn the engine over with the hand crank until the pin pops into the dimple. You may be able to turn the engine over back and forth with the fan blade to get the exact location. With the advance lever all the way up, the points should just be opening at that point. The timing has to be fairly exact.
 
There are some good videos on Youtube for how to set the timing on a Model A. But before you do, make sure the points are clean and the gap is set correctly and that you have verified that there are no shorts or open circuits. One video recommends that the timing be set with the advance lever one notch down which makes a lot of sense to me. That way the full advance is about 30 degrees and with the lever fully up the timing is about 4 degrees retarded, which allows you to hand crank the car without worry of kickback.

If this is all confusing to you and you don't feel confident to do the job correctly, please get some help from an experienced Model A owner. It really only takes 30 minutes to do it correctly if you know what you are doing.
 
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