Ran fine...won't start 31 Coupe.

Auernig

Junior Member
I'm stuck...

I've been driving my 31 coupe around town all summer. It's been running great with no problems. Last night, I drove it to a friends house and tried to start it a couple of hours later but it won't start. It always starts with the text book settings; spark rod up, 2 clicks down on the throttle, 3/4 turn out on the GAV and choked.

I checked the timing and its dead on. I checked for spark and the plugs are firing just fine. I checked the gas line, nice full flow into the carburetor (Zenith 1) It cranks like normal.

I think the issue is however carburetor related. I unscrewed the main carb screw and dropped the bowl. The float seemed a little odd to me. I felt like I had to push it up hard to get the gas flow to stop. I have a carb kit and may just replace the tip (viton). Float itself seems fine. I rebuilt this carb a year ago and its run great all year. Even drove it in the 4th of July parade without issues.



Here are my questions:
1. If the float wasn't working, would it flood out the carb and therefore not allow the jets to work properly?

2. What else could it be? (Carb or otherwise)

THANK YOU!!!
 
Yes if the float hung up open ,then you would have gas dripping out of the throat.if it stuck shut, then no gas would fill the bowl. That being said, did you shut the gas off and run it out before shutting it off? If not ,then the bowl should have had enough gas to sputter or run for a short while. We're the plugs wet? One way to check for gas starvation is spray a small amount of starter fluid in the throat and see if it tries to fire.
 
I have the same problem, with the same pre-amble. So I will watch with great interest the many experienced answers that this forum is noted for.
 
In my experience, these symptoms suggest an electrical problem, not a fuel problem. I suggest checking for spark at the points. It is unlikely that timing would change unless the timing gear stripped or the cam/distributor gear stripped. This can be checked by removing your distributor cap and turnidng the engine over to see if the rotor turns. No turn? Stripped gear. No spark? Suspect the lower plate pigtail.
 
Maybe you have it flooded. Try cracking the hand throttle open about half way and don't choke it any. Spin the starter over if it fires get ready to push the throttle lever back up you could also clean the plugs if they are wet. Frank
 
Always start by doing a simple test to see if it's fuel or spark related. This will save a lot of work and guessing. I usually start by holding the coil wire 1/4" from a head nut to check for a hot blue spark. You could also start by pulling the choke for a couple revolutions, then look for gas dripping out of the carb.

I had the same problem about 6 years ago when I had corn crap gas in the tank and the temp was in the upper 80's. I was parked for a couple hours and the engine wouldn't start again. It did fire a couple times at first, but then nothing. It was the crap gas had boiled away and left the carb dry. I had to remove the fuel line at the carb to get the crap gas to start flowing again. Four hours later the problem repeated itself, so I knew right away what to do.
 
I have had the float stick in the up position and it took a little tap on the bowl to free it up. If this happened, it would run for a short time until the bowl ran dry.
How about that gas cap not venting? That would do it also.
 
Always start by doing a simple test to see if it's fuel or spark related. This will save a lot of work and guessing. I usually start by holding the coil wire 1/4" from a head nut to check for a hot blue spark. You could also start by pulling the choke for a couple revolutions, then look for gas dripping out of the carb.

I had the same problem about 6 years ago when I had corn crap gas in the tank and the temp was in the upper 80's. I was parked for a couple hours and the engine wouldn't start again. It did fire a couple times at first, but then nothing. It was the crap gas had boiled away and left the carb dry. I had to remove the fuel line at the carb to get the crap gas to start flowing again. Four hours later the problem repeated itself, so I knew right away what to do.


what tom said, some simple diagnostic steps to point you in the right direction
 
No luck yet ?
You say you have good spark at the sparklers and good fuel flow to the carburetor.
So, when cranking, do you have fuel dripping from the carb throat ?
If the sparklers are dry and the throat is dry then I'm thinking you may well have a stuck float. If you removed the carb bowl, how did it look ? If clean I'd look to the float first. If dirty, then the jets/passageways could well be clogged.
 
Are all of your carburetor passageways clear of obstructions? It sounds like you are getting gas into the carb and you do have spark at the plugs but you may not be getting gas to the cylinders.
 
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