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Discussion Starter · #1 ·
Tried starting my 69 the other day and after sitting in the garage like usual I had to prime it, it seems if it sets for more than a week at a time the fuel bowl is empty and I have to go thru that ritual. I have just been putting off the obvious! Just wanted a second opinion on this, the car would only run when primed, I took off the fuel line and it seemed to pump out fine, I think that the needle/seat is bad and not allowing gas into the fuel bowl, thus keeping the acelarator pump from shooting gas due to no fuel in bowl. I know the shot pump as the older guys call them are made of leather or rubber flange type material and wear out with time and believe the problem lies with the needle valve and seat. Correct me if I am overlooking anyting obvious.I am planning on buying a kit and replacing both the needle/seat and accel. pump and believe the first will take care of the problem. It is a 351-w with the factory ford 4bbl. on it so it appears pop the top with about 6 screws, disconnect some linkage, replace and reinstall.
Thanks, For the suggestion
 

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Are you sure the fuel bowl is empty? A week is not a long period of time for the bowl to just dry out. It's also an emmisions carb, so it is not as vented as the earlier type. If the bowl is empty, maybe you have a leak somewhere. If you go the rebuild route, use carb dip and make sure all the passages and air bleeds are clear - and there's a bunch of them. Also look for warpage on the throttle plate.
 

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I assume it has a mechanical fuel pump?

I have wondered about this problem before. My brother in law's motor home does the same thing. It has an old carb'd 460. If we spray some starter fluid in the carb it cranks fine but it won't pump up on its own. After we get it started it will crank back up fine for several days but eventually it quits cranking up by itself again.

I wonder if air gets in the fuel line between the pump and carb and the old mechanical fuel pump doesn't push enough to push it out.

My hot rod has an electric fuel pump and sometimes sits for a few weeks without being cranked. I never have to prime it up. I hit the fuel pump switch, wait a few seconds, tap the gas a couple of times and it fires immediately.
 

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Is your choke mech. or electric? I found out that my car won't fire off unless I allow the choke to come in and put up the fuel. This is a 351CJ with a 750cfm 4bbl Holly. After that initial fire off it will want to die at least once until warmed up.
 

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Discussion Starter · #6 ·
My car has the stock mechanical pump on it. I assume the fuel bowl is empty as its primed and it will take off and then be OK, this time it won't stay runnung as it is not getting any gas, and I don't even smell the gas when cranking it, after verifying it is pumping out of the line.
The car does have the factory auto choke, and it was on , I'll give it another shot when it warms up by the end of week! Thanks to all.
 

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Rap on the side of the carb with the handle of a large screwdriver. It works best when the engine is running (from a prime) as then you have fuel pressure on your side. You at least have a stuck needle seat. Do you have rust in the tank? This can choke off the flow of gas making it so less gas resides in the bowl. This would allow for faster evaporation because there is less gas to evaporate. The usual sign is that you can overcome gas starvation with a prime. You may want to drain your gas tank and remove the sending unit to check for rust. You can also take the top off the carb to see if there is gas in the bowl, and if there is brown dust at the bottom of the bowl - it's rust.
 

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Both my Holley and my Edelbrock have done this on my '65. Usually took about a week for bowl to go dry...I always assumed it was because it was a non-emissions type carb and was venting to the outside.

With the Edelbrock I went with one of these (part no SUM-G1523) from Summit...that way I always know when the pump gets the fuel to the bowl, or at least to the needle and seat.
 
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