Fuel tank question
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Joined: Mar 2011
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From: SoCal California
Fuel tank question
I have a 1969 Corvette L-71 that I am in the midst of restoring. When I removed the fuel tank I noticed two lines: one line was the main feed line and another line had a small piece of fuel line on it that was capped off. I can't think this "capped off" is original ... so the question is, what SHOULD it be connected to?
I'm guessing that the second line tied into a smog-related charcoal canister or such, but at the rear of the car there are no factory type metal lines that give indication of a connection point for a breather or smog related setup.
Anyone have some insight?
I'm guessing that the second line tied into a smog-related charcoal canister or such, but at the rear of the car there are no factory type metal lines that give indication of a connection point for a breather or smog related setup.
Anyone have some insight?
Burning Brakes
Joined: Jul 2009
Posts: 912
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From: Kansas City MO
I may be incorrect, but my .02 would be that the other line you are referring to was for the fuel return line.
Maybe the previous owner installed a different fuel pump that did not have a connection for the return line? Quite possibly this is why you found the other line to be capped off?
Maybe the previous owner installed a different fuel pump that did not have a connection for the return line? Quite possibly this is why you found the other line to be capped off?
Burning Brakes
Joined: Apr 2011
Posts: 975
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From: Phoenix, AZ
I may be incorrect, but my .02 would be that the other line you are referring to was for the fuel return line.
Maybe the previous owner installed a different fuel pump that did not have a connection for the return line? Quite possibly this is why you found the other line to be capped off?
Maybe the previous owner installed a different fuel pump that did not have a connection for the return line? Quite possibly this is why you found the other line to be capped off?
Team Owner
Joined: Jan 2006
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From: Crossville TN
The 1969 A.I.M. will depict the "correct" setup for that tank fitting, so I would suggest that you use it as reference on whether it is capped or used.
Be aware that the 'base' car configuration is how the A.I.M. is designed, with details on optional configurations being shown within those specific options. If that fitting is capped for the base unit, you still need to check under the L-71 option sheets to see if it is used differently there.
Be aware that the 'base' car configuration is how the A.I.M. is designed, with details on optional configurations being shown within those specific options. If that fitting is capped for the base unit, you still need to check under the L-71 option sheets to see if it is used differently there.
Team Owner
Joined: Sep 2006
Posts: 31,274
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From: Westminster Maryland
Hi CW,
I believe that in 1969, L-71 (435 hp and Holley) equipped cars used only 1 fuel line and no return line. The quadra-jet equipped cars cars used a return line.
I wonder if either the tank or engine has been changed on your car?
I believe that in 1969, L-71 (435 hp and Holley) equipped cars used only 1 fuel line and no return line. The quadra-jet equipped cars cars used a return line.
I wonder if either the tank or engine has been changed on your car?
Melting Slicks
Joined: Jan 2012
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From: myrtle beach sc
Army
As far as I know, the fuel return line always came off of the special AC fuel filter to eliminate vapor lock. Not off of the fuel pump. Lou.
Last edited by loup68; Oct 27, 2012 at 03:50 PM.
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Joined: Mar 2011
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From: SoCal California
7T1vette,
What is A.I.M? I've heard of A.I.R. ... in other words, the air injection setup that was part of the smog system.
+++++++++
Alan 71,
The L-71 427 V-8 is original to my car. However, who knows if the fuel tank was changed at some point over the years.
Two questions:
1. Does anyone have info or a photo of the fuel pump used on a 1969 L-71 (in other words, did it have a port used for a return fuel line)?
2. What should be the correct numbers cast into the fuel pump for a factory-correct L-71 in 1969?
3. If a 1969 Corvette had an L-71, did it still get the regular fuel tank with a return fuel port on the upper edge (the style that was used with non-L-71 Corvettes)? If so, was it simply plugged from the factory?
What is A.I.M? I've heard of A.I.R. ... in other words, the air injection setup that was part of the smog system.
+++++++++
Alan 71,
The L-71 427 V-8 is original to my car. However, who knows if the fuel tank was changed at some point over the years.
Two questions:
1. Does anyone have info or a photo of the fuel pump used on a 1969 L-71 (in other words, did it have a port used for a return fuel line)?
2. What should be the correct numbers cast into the fuel pump for a factory-correct L-71 in 1969?
3. If a 1969 Corvette had an L-71, did it still get the regular fuel tank with a return fuel port on the upper edge (the style that was used with non-L-71 Corvettes)? If so, was it simply plugged from the factory?
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Team Owner
Joined: Sep 2006
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From: Westminster Maryland
Hi CW,
The AIM is the ASSEMBLY INSTRUCTION MANUAL. There's 1 for each year and it was used on the production line in St.Louis. In the optional equipment section you'd be able to see what all was part of, or was deleted from, the car when the L-71 option was selected.
The original L-71 fuel pump wouldn't have had an extra fitting.
Although Chevrolet did some pretty 'strange' things they would not have installed a fuel pump or fuel tank with extra fittings or nipples on a car that didn't need them and thus would have needed to have been 'blocked' off.
Regards,
Alan
This is the typical tank, passenger's side, of a car with the fuel return line. A car without return line would not have had the nipple.
The AIM is the ASSEMBLY INSTRUCTION MANUAL. There's 1 for each year and it was used on the production line in St.Louis. In the optional equipment section you'd be able to see what all was part of, or was deleted from, the car when the L-71 option was selected.
The original L-71 fuel pump wouldn't have had an extra fitting.
Although Chevrolet did some pretty 'strange' things they would not have installed a fuel pump or fuel tank with extra fittings or nipples on a car that didn't need them and thus would have needed to have been 'blocked' off.
Regards,
Alan
This is the typical tank, passenger's side, of a car with the fuel return line. A car without return line would not have had the nipple.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
Melting Slicks
Joined: Sep 2007
Posts: 2,149
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From: cary Il
I know on my LT-1 cars, the tank has only one outlet for fuel, no provitions for a return line. canister vent on drivers side, so either you have the wrong tank or wrong motor.and 69 fuel pumps had no return, only on the fuel filter.
Instructor
Joined: Dec 2009
Posts: 107
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my '69 vett is a L46 (350 350) and it has 2 fuel lines. a 3/8 inch line from the bottom of the fuel tank to the fuel pump then up through the fuel filter to the carb. the other is a 1/4 inch fuel return line from a 1/4 inch nipple on top of the fuel filter back to the tank and connected with rubber fuel line up to a nipple on the top of the tank pass. side.