rayclay Posted October 23, 2009 Share Posted October 23, 2009 My original engine & carb are rebuilt and start/run perfectly. My problem occurs after a 10 minute or longer drive. Three minutes after stopping, my Stromberg carb begins leaking raw fuel down the throat. It starts with a slow drip and accelerates to a steady stream of fuel for 3 to 6 minutes! Restarting when warm means holding the accelerator down as the engine cranks because it is severely flooded. Some fuel actually creeps out of the butterfly valve flange. Two local mechanics (and an owner) are baffled! Has ANYONE ever heard of symptoms like these? Help! Ray Link to comment Share on other sites More sharing options...
davenc Posted October 23, 2009 Share Posted October 23, 2009 Rayclay, I definitely feel your pain with the Stromberg EE22 carb. My '36 is a constant source of carb-tinkering. If the fuel pump was on a pressure stroke when you shut the car off, the air under pressure in the pump's air dome will push the fuel in the fuel line up to the carb and overflow the float bowl. Check the check valve in the intake manifold drain tube. Make sure the check valve is not stuck shut. Excess fuel down the throat of the carb is supposed to drain out the check valve and puddle under the engine. The check valve is in the elbow of the drain tube. It does come apart. Make sure the little ball is seating properly. Dave Link to comment Share on other sites More sharing options...
rayclay Posted October 23, 2009 Author Share Posted October 23, 2009 Dave: Knowing that my EE22 problem isn't unique is somewhat comforting. I just removed an electric fuel pump a previous owner installed. It put out 7 pounds of pressure and an inline regulator set to 3 pounds didn't stop the symptoms. My rig runs just fine now with it's original pump. I was about to insulate my fuel line thinking engine heat was causing the gas to expand. Will the raw fuel trickling down the carb after shut off damage my engine? I thought it might dilute/compromise the crankcase oil. I'll quickly inspect the check valve. Thanks, Ray Link to comment Share on other sites More sharing options...
michaelod Posted October 23, 2009 Share Posted October 23, 2009 Anytime you have raw fuel exiting out the carb, you have a real potential for fire. I think that would be my first concern.Michael Link to comment Share on other sites More sharing options...
davenc Posted October 23, 2009 Share Posted October 23, 2009 Rayclay, I made the assumtion you had the original AC style fuel pump for a '36, 320 cu. in. engine. This pump has an air dome on the top of the pump. As long as the raw fuel is dripping down inside the carb, and not outside, the intake manifild drain pipe should be draining it and the gas does not get to the crankcase. Check the check valve and if that doesn't fix it, we'll explore other things. Dave Link to comment Share on other sites More sharing options...
Buicksplus Posted October 25, 2009 Share Posted October 25, 2009 I have had this problem with my 40 LaSalle. It does the same sort of thing with both a Stromberg or Carter on the car. I used to have a 39 Buick 320 that had similar symptoms.I believe the flooding is simply due to the boiling off of gasoline in the bowl when the engine stops. The carburetor heats considerably when the engine is shut off, remember it is sitting on top of the exhaust heat riser. This causes expansion of the gasoline, it bubbles up and flows out through the jets into the intake manifold and even out the top of the carburetor. This does not happen with the engine running because the carb gets cooled by the steady infusion of cool, fresh gasoline from the tank. There is not much you can do about it. I found fuel pressure or even lowering the fuel level had little effect. The high volatility of today's gasoline exacerbates the problem. I think it does little harm except the car is badly flooded when you try to start it within 15 minutes or less after you shut it off. It takes wide open throttle to get it to start, and the car bucks and surges for a mile or two, but then it smooths out when the gas finally cools off the bowl. I now have my LaSalle running on the electric pump only. If you do that, you can shut off the pump before you stop the engine and let it run out of fuel. This will stop the flooding on restart, but it is a tedious process.Bill. Link to comment Share on other sites More sharing options...
garnetkid Posted October 25, 2009 Share Posted October 25, 2009 I posted this article by Dave Botting on this site awhile back. It may be the solution you are looking for , Leon file:///Users/leonrumpf/Desktop/http-::i62.photobucket.com:albums:h9...kid:img257.jpg.webloc Link to comment Share on other sites More sharing options...
garnetkid Posted October 25, 2009 Share Posted October 25, 2009 OK, that doesn't want to open, will try something else. Leon Link to comment Share on other sites More sharing options...
garnetkid Posted October 25, 2009 Share Posted October 25, 2009 try again.http://i62.photobucket.com/albums/h97/garnetkid/img257.jpg Link to comment Share on other sites More sharing options...
Mark Shaw Posted October 25, 2009 Share Posted October 25, 2009 Good solution with the added benefit of constant cooling of fuel through the bypass. Link to comment Share on other sites More sharing options...
Bob Engle Posted October 26, 2009 Share Posted October 26, 2009 Why go all the way back to the gas tank with the bleed line? Just Tee into the suction line before the fuel pump and it should relieve the pressure.Bob Link to comment Share on other sites More sharing options...
garnetkid Posted October 26, 2009 Share Posted October 26, 2009 Bob, that won't work as most of the problem is fumes. I did talk to the author of the article and he advised that he did try that at first and was not satisfied with the results. What he ended up doing with his (1936 Buick) was relocating the the fuel line from the top of the tank to the drain plug opening at the bottom of the tank using one of those skinny mesh filters. He then used the original outlet on the tank to run the vent line into. I guess this fix would all depend on how original you want to keep the car. He has helped other people with this fix with excellent results. Leon Link to comment Share on other sites More sharing options...
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