What's the best way to drain the gas tank?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Buck69

Full Access Member
Joined
Feb 2, 2023
Posts
227
Reaction score
293
Location
Northern British Columbia
First Name
John
Truck Year
1986
Truck Model
D30 CUCV
Engine Size
6.2 (removed)
You mean you don't have to get gasoline in your mouth? Awesome!

Joking aside I usually just use a small clear hose like a straw and then stop when I see it flowing. It will do the job to get the gas moving. I just need a way to get the tube into the tank.
They actually work really good. I have over 20 5 gal containers I grabbed from a car wash that their detergents come in. 2 will nest perfectly in the large rubbermaid totes. The totes give them extra containment for safety and allow them to be stacked real nice. We use them for extra fuel on extended trips in the boats and trucks. Those little syphon hoses give a quick clean transfer to the main tanks and ya, there is no gas in the mouth or even drips on the ground.
I removed 2/3's of a tank of 16 year old diesel from the saddle tank in the CUCV I just grabbed last weekend with one. Pretty easy as mentioned in my last post accessed through the wheel well.
 
Last edited:

sgrinavi

Full Access Member
Joined
Feb 23, 2022
Posts
52
Reaction score
28
Location
Fort Myers, FL
First Name
Steve
Truck Year
1981
Truck Model
K20
Engine Size
350
I have an electric pump, I just by-pass the oil pressure safety switch, disconnect a hose at the carb or filter and pump it out.
 
Last edited:

TFerguson

Member
Joined
Apr 25, 2022
Posts
36
Reaction score
40
Location
Richmond VA
First Name
Rick
Truck Year
1990
Truck Model
Blazer
Engine Size
350 (5.7)
I can attest to the "screen" (or whatever it is) blocking siphon tube access via the filler neck. I ran into the same hurdle when trying to drain the tank on my '90. Tried several hoses, but they were all denied access. Maybe it's just a TBI feature? But I assumed the same: anti-gas theft and/or possibly also a kind of "pre-filter" in case there's leaves or small bones in your gas can..? Anyway, I just disco'ed the fuel line before the filter, aimed it at a bucket, and connected the fuel pump relay to the battery. Of course, if your pump's fully dead that won't do you much good.
 

Nuckollsr

Junior Member
Joined
Dec 11, 2018
Posts
20
Reaction score
19
Location
Medicine Lodge, KS, USA
First Name
Bob
Truck Year
1987
Truck Model
R1500
Engine Size
4.3L
Yeah, external fuel pump with outlet hose long enough to drop into gas tank on my other car. Works good, doesn't spill a drop. Used it on my '87 twice.
 

gogo14910

Member
Joined
Dec 19, 2021
Posts
45
Reaction score
74
Location
Texas
First Name
Joe
Truck Year
1987
Truck Model
R10
Engine Size
350 SBC
I used a transmission jack to drop my full fuel tank then just dumped fuel on the bonfire pile.
 

Craig Nedrow

NADAR UNDER THE RADAR
Supporting Member
Joined
Sep 1, 2018
Posts
1,036
Reaction score
2,182
Location
Washington State
First Name
Craig
Truck Year
1973 (have two), 1985
Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
I must be missing something. This has two tanks, and a switching valve. If that is right,, you can go underneath and pull the line that connects to the valve from the bad tank, and run it into a container to drain it. . I was way up in the hills this last winter, and ran out of gas in the tank I use. Went under and switched the hoses, cranked to get the fuel to the carb, and made it home. Gas was three years old.
 

Blue Ox

Turning Diesel Fuel Into Fun
Joined
Mar 27, 2018
Posts
5,217
Reaction score
12,010
Location
LI-NY
First Name
Derek
Truck Year
MCMLXXXV
Truck Model
K20HD
Engine Size
6.2L
It is a good point. I have an 87 tank but the older fuel Neck.
I’d be tempted to remove the hose clamp from the rubber fuel neck in top of the tank. Lift t it off and slid the hose in through the top of the tank if your neck somehow has a screen in it.

As long as we're still discussing this, this is what I did on my '85. It's about impossible to get a hose past the bend in the filler. I popped the filler hose off and put a pump suction hose in the tank filler port. You could also use a jiggle hose or the potential "hint of gasoline flavor" siphoning method. Got an inspection camera in there too, trying to figure out why I couldn't draw from that tank.
 

WP29P4A

Full Access Member
Joined
Jul 18, 2021
Posts
889
Reaction score
1,514
Location
Nevada
First Name
Mike
Truck Year
1987
Truck Model
Sierra Classic V1500
Engine Size
350 TBI
If I remember correctly, in the late 70's when the oil embargoes happened and gas prices went crazy, siphoning/stealing gas became a big deal. The manufacturers of vehicles put a simple coiled spring into the bottom of the filler tube, making it real hard to get a hose down past it.
 

82sbshortbed

Fuckemall!!
Joined
Mar 1, 2018
Posts
15,824
Reaction score
53,145
Location
SE Texas
First Name
Doug
Truck Year
1982, 1984
Truck Model
1500 shortbed, 1500 longbed
Engine Size
454, 305
Just mash the skinny pedal to the floor?
 

Radiohead

That guy on the Columbia
Joined
Mar 17, 2022
Posts
2,486
Reaction score
8,110
Location
Low Earth Orbit where it's safer
First Name
Eric
Truck Year
MCMLXXIX
Truck Model
C-20 Silverado Camper Special
Engine Size
454 crazy cubes, or 7.4 luscious litres
If I remember correctly, in the late 70's when the oil embargoes happened and gas prices went crazy, siphoning/stealing gas became a big deal. The manufacturers of vehicles put a simple coiled spring into the bottom of the filler tube, making it real hard to get a hose down past it.
You remember correctly.
I distinctly remember the hint of gasoline flavor, mixed with beer breath trying to get home late, late at night. And that was under a dollar a gallon then - way under.
 

Scott91370

Full Access Member
Joined
Apr 2, 2018
Posts
996
Reaction score
1,019
Location
Burleson, Tx
First Name
Scott
Truck Year
1985
Truck Model
Sierra1500
Engine Size
350
Drill a hole in the bottom?
 

RanchWelder

Full Access Member
Joined
Jan 14, 2023
Posts
798
Reaction score
1,144
Location
Earth
First Name
--------
Truck Year
87
Truck Model
Blazer
Engine Size
355ci
You can ingest three our four ounces of fuel before it makes you puke... man up and do it old school.
It burns your eyes when it come back up through your sinuses though... :flame:
 
Last edited:

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
6,970
Reaction score
12,219
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
The best way to drain the gas tank. You know, the original point of the thread.

I was going to put up a burnout gif, but it would be redundant.
So neither of you read the OPs initial post?
 

Forum statistics

Threads
44,152
Posts
950,457
Members
36,268
Latest member
JUKA
Top