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Gas bypass-low rpm's

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19_again

19_again

Jedi Warrior
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It's about time to get 19again on the road, the new harness is in and I was just starting it today and the idle speed seemed very low. after the car sat in neutral idling at the lower rpm's I noticed that the fuel was pooling on the floor. I believe there is a bypass that dumps the fuel rather than feeding the carbs when the rpm's don't warrant that much gas, is this true. It didn't seem to "overflow" when I had the choke out (higher rpm's). It idles kind of rough and at lower rpm's than it used to. I just finished the harness, over the winter had the rocker assy. redone and haven't put one mile on it yet so haven't adjusted the idle yet, but wanted an answer to the issue of gas leaking or overflowing before I went any further. What are your experiences and suggestions?
 
Sounds like a float valve is bypassing and it's flooding the fuel bowl. What carbs do you have?
 
Pull BOTH float covers and clean out the sediment in the bottoms. Take care to hog out the really fine stuff that has accumulated in the two little chambers in the bottom of each one. An ice pick and repeated dosing with carb cleaner and a clean rag will help lots.

Then blow through the cover inlets to dislodge any debris from the valve seats. After that run six or eight ounces of gasoline into a clear class container. Have someone turn the ignition key on while you stand by the car and direct the flow from the disconnected hose. Let the fluid settle for a while and inspect it by using a light behind the glass. You are looking for hard debris and water that will either settle to the bottom or make the mix rather cloudy.

It would probably be a good idea to replace the fuel filter several times over the next hundred miles or so as condensate and general gunk can build up in a tank that is less than full over a period of time. Do take care when changing the filter to NOT scrape the insides of the rubber hose connections. If you do the scraping often peals off small shreds of rubber that in turn move on to the needle and seat in the float chambers and hold them open causing a repeat of what you are experiencing now.

Jack
 
Thanks Jack,
You know I forgot to mention that I had patched a small leak in the tank over the winter. In cleaning out the worst of the 40 years of who knows what, I'm sure I left a lot of gunk in there myself. Since that time, we have only started it for seconds at a time in testing harness connections. Do you think that the it appears to dump the fuel out the bypass tube only at low rpms 500-900 is important?
Mike
 
Well Jack and Paul, the bowls had enough crud in them, rear mostly, that I could insert my small computer screwdriver into the well on either side of the feed trough and upon removal it had schmuts stuck to it. Cleaned them both up real nice and no more leaking.
Another typical example of why this site is worth paying for, thanks all.
 
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