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Welcome to FordPinto.com, The home of the PCCA => General Help- Ask the Experts... => Topic started by: russosborne on May 31, 2009, 12:16:53 AM

Title: Two fuel lines from sending unit???
Post by: russosborne on May 31, 2009, 12:16:53 AM
Once again I am showing my ignorance of Pintos, or maybe just newer cars in general. And of course the Hayne's manual is useless concerning this. I really need to get a 1979 factory service manual I suppose.

Sorry, forgot to mention it is a 1979 hatchback with a 2.3L and and automatic trans.

Got under mine today to fix a gas leak, found 2 lines coming from the gas tank fuel sending unit. Plus a third line going towards the fuel filler tube from the front of the car, I didn't look that far once I was sure it wasn't the one leaking.
I figured out that the larger line must be the one that supplies the fuel pump, and that was the one leaking. But what is the other one for? I know that fuel injected cars have a return line, but this is a carb'ed car. This unknown line has a lot of rubber hose on it. Since all the smog stuff was removed by a previous owner, I guess my main question is can I just remove most of the line and just plug up the end on the sending unit?

Thanks.
Russ
Title: Re: Two fuel lines from sending unit???
Post by: r4pinto on May 31, 2009, 12:14:49 PM
I believe it still has a return line  so no, I would not plug it up. Best books you could find is either a Motor manual or the 79 factory service manual. The chilton book is just as worthless as the haynes book.
Title: Re: Two fuel lines from sending unit???
Post by: blupinto on May 31, 2009, 12:19:54 PM
r4 is right. You don't want to plug the other line. Bad things could happen.  :hangover: Aren't sending units fun?  :P
Title: Re: Two fuel lines from sending unit???
Post by: r4pinto on May 31, 2009, 08:33:26 PM
You know it Becky.. I am right again... I need to mark this in my book hehe
Title: Re: Two fuel lines from sending unit???
Post by: russosborne on June 03, 2009, 12:24:39 AM
Thanks.
What does the return line hook up to in the engine compartment? Like I said, all of the smog stuff is missing from this car. There are a whole bunch of hoses just kind of tied off on the drivers side fender well.
That's why I am wondering about plugging it. If it isn't hooked up to anything why keep it and have to worry about leaks, assuming that since it does come from the tank it could get gas in it, unless it has a check valve for one way operation.
I don't know, my mechanical knowledge pretty much ends around the 1970 time frame.
Russ
Title: Re: Two fuel lines from sending unit???
Post by: popbumper on June 03, 2009, 04:29:57 PM
Russ:

  Both the supply fuel line and the return line hook up to the fuel pump. When engine compartment temps cause vaporization of the fuel, the vapors are "recollected" and sent back to the gas tank to be recirculated. This aids in fuel distribution so that the intake does not see an overabundance of vapors, causing surges in power.

  The third line from the tank, the vapor collect line, lierally funnels the vapors from the tank above the liquid gas to the charcoal canister under the fender, where is is "stored" until scooped up by the carb. This line not only helps void the tank of pressure, but allows the system to use any excess vapors.

Hope that helped.

Chris
Title: Re: Two fuel lines from sending unit???
Post by: blupinto on June 03, 2009, 11:33:05 PM
Quote from: r4pinto on May 31, 2009, 08:33:26 PM
You know it Becky.. I am right again... I need to mark this in my book hehe
You lil' snot! lol.
Title: Re: Two fuel lines from sending unit???
Post by: russosborne on June 04, 2009, 05:08:06 PM
Thanks, Chris. I hadn't realised that the second line also went to the fuel pump.
I really need to get an older car that I understand.
Russ
Title: Re: Two fuel lines from sending unit???
Post by: popbumper on June 04, 2009, 08:48:41 PM
Glad to help! An older car you'd understand - I just wish I had a car I >could< understand  :lol:

Chris
Title: Re: Two fuel lines from sending unit???
Post by: pintoguy76 on June 25, 2009, 08:59:38 PM
Two of my pintos have electric fuel pumps because for some reason they will no longer pump with a mechanical pump. The electric pump doesnt have a spot for a return line. So i have the return line plugged. Is there something else i should be doing?
Title: Re: Two fuel lines from sending unit???
Post by: hellfirejim on July 03, 2009, 05:55:05 PM
What is the first year for a return line to the tank