Dual Weber 40’s, Fuel lines |
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Dual Weber 40’s, Fuel lines |
KevinW |
May 22 2020, 11:43 AM
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#1
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Newbie Group: Members Posts: 42 Joined: 25-May 15 From: Winona, Minnesota Member No.: 18,761 Region Association: Upper MidWest |
I am looking for a drawing or detail Or picture how to route the fuel lines. I have searched the web but no luck. I have an idea about the supply line but not sure about the return line?
Thanks |
bbrock |
May 22 2020, 01:48 PM
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#2
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
There is another reason to keep the return line. The reserve fuel system depends on it. In the pic below, you can see that the supply line drains from a bowl in the bottom of the tank and the return dumps fuel back in it. This allows the system to constantly scavenge fuel from the tank and concentrate it in that bowl so you can use all of the fuel before sucking air. I've read of people complaining that their car was running out of gas with the gauge showing 1/8 or more of a tank after switching to carbs. I'm guess this is why.
(IMG:http://www.914world.com/bbs2/uploads/post-20845-1587959064_thumb.jpg) |
Superhawk996 |
May 22 2020, 02:05 PM
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#3
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914 Guru Group: Members Posts: 5,673 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
There is another reason to keep the return line. The reserve fuel system depends on it. In the pic below, you can see that the supply line drains from a bowl in the bottom of the tank and the return dumps fuel back in it. This allows the system to constantly scavenge fuel from the tank and concentrate it in that bowl so you can use all of the fuel before sucking air. I've read of people complaining that their car was running out of gas with the gauge showing 1/8 or more of a tank after switching to carbs. I'm guess this is why. (IMG:http://www.914world.com/bbs2/uploads/post-20845-1587959064_thumb.jpg) Good point but not entirely correct. You can run them dry without a return line. Ask me how I know. (IMG:style_emoticons/default/laugh.gif) Fuel will still enter the "coffee can" as low fuel sloshes to and fro. You'll notice the holes in/out of the coffe can are quite small. So they effectively act as an orifice to restrict flow out of the can concentrating fuel around the pickup inlet. Also the inlet is situated at the low point and all other sufaces slope toward the coffee can to try to feed it. In my case I did get episodes of running then stalling that came a mile or so in advance of when I had to walk to the gas station so I'll readily concede that a return line may have helped prvent that. But at the end of the trip, when the gas is gone, your walking. (IMG:style_emoticons/default/sad.gif) I'm wondering if those with the 1/8 tank scenario were running around with debris plugging the coffee can in/out orifice holes. Fully concur that return line is the modern, proper solution that will help cool fuel and reduce vapor lock. I did what I did (not using return) before I knew any better. |
bbrock |
May 22 2020, 03:27 PM
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#4
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
I'm wondering if those with the 1/8 tank scenario were running around with debris plugging the coffee can in/out orifice holes. I just assumed the engine was being starved when they cornered. Obviously if the car is running level you would be able to run them dry because I don't think the supply/return tubes make a liquid tight seal with the can, but that isn't how we are supposed to drive these cars. (IMG:style_emoticons/default/biggrin.gif) I would prefer to have my last quart of fuel in that bowl rather than sloshed up against the far end of the tank. Also, with the orifice holes half way up the sides of the can, I'm not sure how much fuel would wind up sloshing into the can when the tank gets low. I also ran a 914 and a bus on carbs without return lines. I really can't remember if there were any issues with stuttering as the tanks got low. Didn't do a lot of hard cornering in the bus though as I had an annoying habit of not wanting to tip it over. (IMG:style_emoticons/default/laugh.gif) |
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