[The following article pairs well with Starting Your Flooded Rotary. Note, though, that unlike the latter, this article focuses on what repairs are recommended to further avoid the problem and only briefly mentions restarting a flooded engine. - RR]

Dave's suggestions:

The symptoms:
Every so often the engine starts to idle very rough and then stalls out. Then it will not start again. When I check the carb, I find fuel literally flooding in through the primary bowl overflow. I've checked all the obvious stuff which I've itemized below.

Dave's diagnosis:
Been there, done that. The float bowl has an electric solenoid that vents to the overflow tube when energized, and vents to the charcoal cannister when off. If the vent solenoid is disconnected or malfunctioning, pressure in the bowl builds up and pushes the fuel out the overflow. Check two things:

1. Make sure the vent solenoid is hooked up and working. If it is intermittant, check the wires and or replace it. You can jumper it to the battery to make sure its not a wiring problem.

2. Make sure the vent line from the gas tank to the charcoal cannister is intact and not plugged. This can pressurize the tank and make it force gas into the float bowls and up thru the vent, usually only noticeable after running for a long time and then trying to idle.

The opinion of the unknown rotary enthusiast:

What to do after the engine has flooded:

1. Remove the upper spark plugs, pull the trigger wire from the trailing coil (that's the coil connected to the spark plugs just removed) and crank the engine to flush any liquid fuel from the engine.
   
   

2. Put spark plugs back in, reconnect trigger wire, ready.
   
   

How to stop it from flooding again while driving:

1. Pull the fuel pump fuse when you suspect the carbs are about to flood (this will most likely be in stop-and-go traffic). Get familiar with the location of this fuse (in my '82 it's on the upper left edge of the fuse block) so you don't need to look down while driving. Signs of flooding can be a change of engine note or a smell of gas. The fuel in the carbs will allow for some 3 minutes of idling at 800rpm.
   
   

2. Put the fuse back in after some 20 seconds or more.
   
   

How to fix the problem:

Flooding carbs can be caused by:

• Float/needle assembly:  Dirt in the float bowl got into the needle passage. Open up the carbs, clean out float bowls and needle passages.

• Float misalignment:  When picking up the upper half of the carb assembly (air horn assembly), the distance between the lowest edge of the float and the air horn gasket should be 51mm +/- 0.5mm (2.0" +/- 0.020"). Bend the float seat lip to adjust this distance if not within specs. When holding the air horn assembly upside-down, the distance between the float edge opposite to the hinge should be 16 +/- 0.5mm (0.63" +/- 0.020"). Bend the float stopper to adjust this distance if not within specs.

• Worn or rusty needle valve, leaking float:  Replace defective parts.

• Blocked or leaking fuel return line:  Inspect by blowing air through the fuel return line at the connection for the carbs.

• Leaking fuel tank:  The fuel tank must be air-tight ("pull a vacuum") in order to suck excess fuel back into the tank. When opening the fuel filler cap after running the engine for some time, a hissing sound should be heard. If not, this may well be what caused the carbs to flood.