Doesn't Want to Restart After Running a While

L

ljaynavl

Junior Member
My '31 coupe starts just fine and runs well. After it runs 10-15 minutes, it often won't fire up. Cranks fine, ammeter is moving when cranking. I am wondering if the condenser might be getting too hot and shutting down. I have the 'modern' set up with the non-stock points and condenser.
Would like to hear what folks think. Once upon a time, I had the heat shield under the distributor, but that came out long ago.
Thanks!
 
I think you are on the right track.
It could also be a coil getting tired. I'm sure you already have but I would also check spark plug gap.
 
I would change the condenser as the first step in troubleshooting. If spark is good then I'd start looking at compression. If compression isn't up to snuff, a person can run some MMO in the fuel for a while and see if that makes a difference.
 
It has been posted before to mount a second condenser on the firewall so it is grounded. As soon as the car stalls and won't start put a jumper from the condenser to the coil nut on the passenger side of the car. This makes a new condenser (should work unless the first condenser is totally shorting out then it may not work...but an excellent quick check).https://www.fordbarn.com/forum/showthread.php?t=282017&highlight=jackson+2nd+condenser

Also does the horn still blow when car stalls? If not jump both terminals together on junction box...bypassing a bad amp meter.
 
You might consider changing the condenser...and burnishing the points...also clean the spark plugs and check the gap...check the gap between the rotor and the distributor...Ernie in Arizona
 
My car has a similar issue. I finally figured out that it was flooded. Either there is a small leak in the float valve or the gasoline gets hot enough to boil out and flood the intake. My solution was to leave the gas valve off at the tank when starting when the engine is warm and then turning it on again after the car starts. Works for me. It runs fine after it starts. Starts fine when cold. Not saying this is your issue. Your results may vary.
 
Here's a copy from another post on checking the ampmeter and coil when car is dead.

Now with voltage on both sides of the fuse, move up to the junction box. There should be voltage at both terminals. If voltage is present only on one side the problem is at the ampmeter and you should Jumper the ampmeter for now.
You should have voltage on both sides of the coil. If not,
remove the red wire on the coil and check again. If you now have voltage on both sides, you have a problem further on. If the voltage is still only in one side you have a bad coil.
 
Did you check coil polarity? The two small coil connections are marked + and -. Be sure that the positive coil terminal is connected to the red ignition switch wire. the car will run both ways, but you will get a hotter spark if connected positive going to the ignition switch to points, and finally to ground when points close. I recently corrected a car that was hooked up backwards, and now it runs and starts better.
 
I think we need to determine whether its fire or fuel.

When it doesn't start, check for spark to the plugs. Just set the plug strips 1/4" from a ground or the plug itself and look for the spark while cranking.
Depending on the coil you bought it could make a difference. New condensers from china are pretty much junk. There has been a huge problem with 'modern' upper plate condensers [ late model Ford V8] [ Get the expensive one from NAPA] as well as the plate itself if it is the wireless model. If its wireless just add the wire.

If there is spark then look at the fuel supply. Make sure there is good fuel flow to the carburetor and that the fuel line from the firewall to carburetor always goes downhill [ never level or upwards]. Some bending may be required.
 
I'd follow up on the flooding possibility. Check the intake of the carb for gas following cranking. Shouldn't be any there. My old tractors like to flood when hot.
 
ljaynavl said:
Does not appear to be any spark off the wires to the plugs.
Click to expand...

Read the posts. OP states there is no spark at the plugs. Check the point gap, if its too close that can cause this issue, the next step probably would be to change out the condenser, I hate to tell you to change anything out without verifying but a condenser that shorts is tough, by the time the engine is cool enough to work on and run tests, it will likely start working again.
 
The crap fuel we have today boils & percolates easily. V8s have a problem with flooding & empty fuel bowl. I'm surprised that an A would do this just because of the totally different set up & carb ???
 
mfirth said:
The crap fuel we have today boils & percolates easily. V8s have a problem with flooding & empty fuel bowl. I'm surprised that an A would do this just because of the totally different set up & carb ???
Click to expand...

With gravity feed I found vapor lock hard to believe until it happened to my friends and then to me in our Model A's. Best to use the good gas without corn crap, but even that isn't as good as what we had in the 60's. 4 ounces of Marvel Mystery Oil per 10 gallons of gas is also very helpful.

On hot days and short stops, my Model A will boil the gas in the carb very easily.
 
You must log in or register to reply here.
Back
Top