The two fuel lines on the driver side near the tank are weeping. I searched but am not clear on these two lines. Is one the return and other the vent? They look like they go to the bottom of the tank.

Do I need to drain the tank to replace them? I have replaced the threaded bigger supply hose in the past and drained the tank.

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85 300D Turbo

A picture would help.


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1985 300SD
1983 300D
2003 Volvo V70

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There is 2 Hoses that come out of the Bottom of the Fuel Tanks. And, Yes the Tank need to be drained to change any of the Bottom Hoses.

If the Set Up is stock the Hose coming out of the Tank is attached to a Big 46MM Nut (The Fuel Tank Screen is attached to the Nut). It has a Brass crimped on Collar on one end and plain Hose and a clamp on the other end.
If you grind through or file through the Collar and pry the Collar off it exposes a regular Hose Barb.
Once the Hose Barb is available you can simply buy for 5/16 inside diameter Fuel Hose and a Clamp from any Auto Part Store; that Hose is rated for Diesel.

The other Hose at the Bottom can also be replaced with 5/1`6" ID Hose and is the Fuel Return Hose.

However, I had a Fuel leak and it turned out to be the Steel Tubing had rusted through. So a good inspection in order.

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84 300D, 82 Volvo 244Gl Diesel

Yes, you need to inspect closely. I just picked up a replacement tank and it had a little rust on it, so I treated it.

The INNER small tube is the fuel return.
The outer small tube is the vent....which interesting enough "stops" about 18 - 20 inches FORWARD of where you see the 2 hoses. Look for a steel tube hanging down with a rubber bell shaped thing on the end.

Here's a link to my fuel tank work:
http://www.peachparts.com/shopforum/3130873-post73.html

Here's are 3 pics of the bottom of the fuel tank I'm installing documenting the repair:







Good Luck and let's hope you don't have a rusted thru fuel tank.

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daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

I have a theory on the rust in this area --- I think the rubber boot traps moisture against the tank.

__________________
daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

Tanks for the help.

I will drain the tank and replace them.

__________________
85 300D Turbo

It is not essential that the tank be empty when replacing the vent and return line hoses. The vent should not leak fuel regardless. The return leak won't leak if the tank is near empty.

Even with the tank significantly full, you can replace those hoses with minimal fuel loss if you are quick.

If you are draining the tank, you might want to remove the fuel strainer and inspect/clean it. It's on the other "end" of the tank --- on the other side of the driveshaft/differential.

Report back on what you find.

__________________
daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

I replaced the strainer and hose that come out of it years ago when I got the car. I can't remember if I replaced these other hoses but they are weeping now.

__________________
85 300D Turbo