My 15 Touring has always been hard to restart after stopping from a run on a warm day (85 deg).
It tends to flood even without priming and the throttle mostly open.
Today I tried something new. I closed the mixture screw halfway from its normal (running) position and it started on the first crank. Of course I couldn't get around the side quick enough to open the mixture before it died, but it started again on the next crank with no problems.
So I guess the question is - is this unusual behavior ? Does anyone else have to start a warm engine this way?
Hey Bud, are you running an NH? That's pretty typical from what I understand. NHs like to be leaned out a little or rich ended a touch even at higher or lower speeds while driving. But especially on cranking most folks open them (rich) a touch to start when engine is cold and leave them leaner when starting if engine is warm. It's not really a set it and forget it kind of carb. Not 100% positive but I think most of the stock Ford carbs are about the same, more or less anyway.
Your gas in the carb chamber is boiling on shut down. Use lowest octane gas...
Especially if you are running a brass Holley G..
Add upper valve oil or no lead additive to the gas tank, try 1/4 pint to a tank full...
add more if needed...
Disconnect the heat stove from the manifold to the carb on a hot day...
Reroute the gas line away from the exhaust pipe...
For vapor lock try using a small bottle of 2 cycle oil for each tank of gas in your Ford. This will make your fuel heavier and less likely to vapor lock. You can substitute Marvel Mystery oil, or a small amount of Diesel fuel, all with the same results.
I have doubt's about gas boiling in a up draft carb hanging off the side of the engine?? I have no doubt the snake oil will make extra smoke! Bud.
Don't think its vapor lock as the car starts easily every time with the mixture screw closed.
I should have mentioned the carb is a Kingston L4. Heat stove removed.
Maybe I can find the sweet spot where the mixture is closed enough to start but open enough to run until I can get to the mixture screw and open it to the normal running position.
Just wondering if this is normal. Seth seems to indicate that it is!
I don't think you're flooding. I think you're vapor-locking. Happens in the best of families and the alcohol in today's gasoline sure isn't helping matters in that regard.
I used to have a similar vapor-lock problem with a different kind of antique vehicle. A short stop would make re-lighting almost impossible, even with an electric starter. The answer turned out to be ridiculously simple: Anytime I stopped the engine to refuel or inspect the latrine, I left the hood open and let the hot air rise up and out of the engine compartment. That stone-simple, stupid little trick was enough to keep the trapped fuel in the lines and carburetor cool enough to preclude bubble-boiling. No more vapor-lock!
Now, maybe I'm wrong (happens all the time, just ask my wife) and instead of vapor-locking, you really are flooding, but this is just too easy and cheap a remedy not to at least give a tryŚright?
I have found L-4 carbs to be rich running at best. The one that I had on my '23 provided no-choke starts in FL at 40 degrees, and at best could only get about 12 mpg in town. Changing to an NH like my other cars provided more normal cold starting (needing choke) and 18-20 mpg in town. I believe the flapper design of the Kingston will always provide for a super rich environment on slow idle/high vacuum situations. Under these conditions, a gas engine typically wants a richer mixture, but I suspect that the Kingston's design over-does this a bit.
I think there are both brass and potmetal flappers used in these things (interchangeably?). I know that mine was brass and wonder if it is heavier than the potmetal version and thus tend to run richer?
In any event, I much prefer the NH and have no trouble with them on stem-winders.
Sounds like the float level is a bit too high. L4's are normally great for crank starting, just lacking on power at the encounter of hills.
I will try the hood up method, but I don't understand if its vapor lock, why simply closing the mixture screw allows the car to start immediately ?
Royce, will also lower the float level a tad this weekend and report back.