The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1969 - 1972 Blazers and Jimmys Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-04-2015, 10:20 AM   #1
71swb4x4
Senior Member
 
71swb4x4's Avatar
 
Join Date: Nov 2003
Location: Brookings, SD
Posts: 10,497
How to drain my tank

My Blazer sat in a heated shop for 15 years. I would like to drain the tank without removing it. I have tried to run a 3/8" line down the fill spout but something is catching it near the top of the tank. I have tried starting a siphon from the steel line at the front of the Blazer (going to the fuel pump) but I can't get that going either, I think it's too far to pull it.
I wish I had an electric pump to hook up to this front line.
__________________
Some people are like slinkies, they aren't good for anything, but you can't help but smile when you see one tumble down the stairs.
71swb4x4 is offline   Reply With Quote
Old 10-04-2015, 11:34 AM   #2
jaros44sr
Registered User
 
jaros44sr's Avatar
 
Join Date: May 2006
Location: Philadelphia, Pa. 19454
Posts: 9,421
Re: How to drain my tank

Quote:
Originally Posted by 71swb4x4 View Post
My Blazer sat in a heated shop for 15 years. I would like to drain the tank without removing it. I have tried to run a 3/8" line down the fill spout but something is catching it near the top of the tank. I have tried starting a siphon from the steel line at the front of the Blazer (going to the fuel pump) but I can't get that going either, I think it's too far to pull it.
I wish I had an electric pump to hook up to this front line.
isn't there a section of rubber hose1/2 way down the fuel line on the passenger side, maybe you could disconnect there and let gravity help you
__________________
Semper Fi...Uncle Sam, you da man

All parts offered to help are free, unless otherwise noted

Dont try this stuff in my build thread, unless you have 55 years of mechanical OTJ training
SAFETY FIRST

AS usual, off topic

They say your mind goes second, can't remember the first


Jim
jaros44sr is offline   Reply With Quote
Old 10-04-2015, 12:33 PM   #3
71swb4x4
Senior Member
 
71swb4x4's Avatar
 
Join Date: Nov 2003
Location: Brookings, SD
Posts: 10,497
Re: How to drain my tank

Quote:
Originally Posted by jaros44sr View Post
isn't there a section of rubber hose1/2 way down the fuel line on the passenger side, maybe you could disconnect there and let gravity help you
I will check that out.
__________________
Some people are like slinkies, they aren't good for anything, but you can't help but smile when you see one tumble down the stairs.
71swb4x4 is offline   Reply With Quote
Old 10-04-2015, 12:58 PM   #4
87Skier
Registered User
 
87Skier's Avatar
 
Join Date: Mar 2014
Location: Corvallis, OR
Posts: 711
Re: How to drain my tank

You could also draw through the fuel tank pickup. Depending on the condition of the fuel you may need to clean the tank, replace the sock, and clean the fuel sender. Mine sat for 17 years and my tank was garbage. Hope yours is better.
__________________
1972 GMC Jimmy Custom 4.8L (L20)/6L90E/NP205
1989 Chevy Suburban V2500 350/Turbo 400/4.11 gears
1996 Chevy Suburban K1500 350/4L60E
87Skier is offline   Reply With Quote
Old 10-04-2015, 01:02 PM   #5
71swb4x4
Senior Member
 
71swb4x4's Avatar
 
Join Date: Nov 2003
Location: Brookings, SD
Posts: 10,497
Re: How to drain my tank

The tank could be bad, but I would prefer to take this one step at a time. Siphon the tank empty, add 5 gallons of fresh gas and siphon dry again. Then add 5 gallons of fresh fuel and a clear inline fuel filter and see what we are sucking through it.
__________________
Some people are like slinkies, they aren't good for anything, but you can't help but smile when you see one tumble down the stairs.
71swb4x4 is offline   Reply With Quote
Old 10-04-2015, 03:07 PM   #6
raggedjim
Senior Member
 
raggedjim's Avatar
 
Join Date: Jun 2002
Location: Murray, Kentucky
Posts: 3,370
Re: How to drain my tank

If you are going to siphon it out you can drop it while it's empty. I dropped mine this spring to replace the sending unit. It wasn't that bad. It will have more rust than you expect.

I had to siphon by removing the hose between the tank and the filler neck.

Rg
__________________
Roger

'68 Short step - https://67-72chevytrucks.com/vboard/...d.php?t=849675
'69 ('70?) 2wd Blazer
'70 GMC Jimmy 2wd
raggedjim is offline   Reply With Quote
Old 10-04-2015, 05:40 PM   #7
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: How to drain my tank

you can use pressure to the gas filler neck to get the junk out me i'd use 15-20 lbs at most
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 10-04-2015, 05:50 PM   #8
71swb4x4
Senior Member
 
71swb4x4's Avatar
 
Join Date: Nov 2003
Location: Brookings, SD
Posts: 10,497
Re: How to drain my tank

Quote:
Originally Posted by cdowns View Post
you can use pressure to the gas filler neck to get the junk out me i'd use 15-20 lbs at most
I considered this but really hate to put too much in and mess something up. I need to check the regulator on my compressor, if it goes down to 15 psi I might give it a try.
__________________
Some people are like slinkies, they aren't good for anything, but you can't help but smile when you see one tumble down the stairs.
71swb4x4 is offline   Reply With Quote
Old 10-05-2015, 02:25 PM   #9
cleszkie
Registered User
 
cleszkie's Avatar
 
Join Date: Feb 2003
Location: Santa Ana, CA
Posts: 2,191
Re: How to drain my tank

You answered your own question. Get an electric pump, hook it to you fuel line and pump the old gas into a bucket.
cleszkie is offline   Reply With Quote
Old 10-05-2015, 11:33 PM   #10
68panelman
Registered User
 
68panelman's Avatar
 
Join Date: Jan 2011
Location: Delaware and Long Island, New York
Posts: 3,450
Re: How to drain my tank

^ exactly, cheapest fuel pump with cans a ready!
68panelman is offline   Reply With Quote
Old 10-06-2015, 11:40 AM   #11
kwmech
Senior Member
 
Join Date: Mar 2003
Location: Colfax-California
Posts: 8,389
Re: How to drain my tank

I recently had a similar problem with a dirty tank and dirty fuel. Get it over it trying to do it 'cheap'. Prepare to pull the tank and have it cleaned out and epoxy coated. I drained my tank and did a refill. The fresh fuel loosened up the "varnish" in the bottom of the tank and even with 2 fuel filters it managed to get through and messed up the carb. I pulled the carb to rebuild.....again.... only to find that the fuel had also coated the intake and runners into the heads. Now I had to pull the intake to have that cleaned out also. Do yourself a favor and just do it right the first time, I learned the hard way, and my tank only sat for 3 years
kwmech is offline   Reply With Quote
Old 10-07-2015, 04:36 AM   #12
87Skier
Registered User
 
87Skier's Avatar
 
Join Date: Mar 2014
Location: Corvallis, OR
Posts: 711
Re: How to drain my tank

Quote:
Originally Posted by kwmech View Post
I recently had a similar problem with a dirty tank and dirty fuel. Get it over it trying to do it 'cheap'. Prepare to pull the tank and have it cleaned out and epoxy coated. I drained my tank and did a refill. The fresh fuel loosened up the "varnish" in the bottom of the tank and even with 2 fuel filters it managed to get through and messed up the carb. I pulled the carb to rebuild.....again.... only to find that the fuel had also coated the intake and runners into the heads. Now I had to pull the intake to have that cleaned out also. Do yourself a favor and just do it right the first time, I learned the hard way, and my tank only sat for 3 years
x2. I had a similar experience. I would say if you open the gas cap and it smells like varnish, pull the tank.
__________________
1972 GMC Jimmy Custom 4.8L (L20)/6L90E/NP205
1989 Chevy Suburban V2500 350/Turbo 400/4.11 gears
1996 Chevy Suburban K1500 350/4L60E
87Skier is offline   Reply With Quote
Old 10-07-2015, 07:28 PM   #13
chastain90
Registered User
 
chastain90's Avatar
 
Join Date: Jul 2009
Location: Chatsworth Ga
Posts: 400
Re: How to drain my tank

Its super easy to drop and if its heavy with fuel just put a floor jack under it with a piece of plywood and ease it down. I dropped mine and had it boiled and lined it with por 15 tank sealer. Really helps get the rust out and keep it out. And you can go ahead and take compressed air and blow all the lines out while the tank is out. Really worth it to get all the junk out of the tank and lines. JMO.
chastain90 is offline   Reply With Quote
Old 10-19-2015, 12:30 AM   #14
vancelot69
Registered User
 
vancelot69's Avatar
 
Join Date: Jul 2014
Location: Lakewood, Co.
Posts: 219
Re: How to drain my tank

I removed the rubber filler hose from the curved neck on the tank then ran my siphon hose into the tank from there and was able to drain it no problem.
__________________
My toys:
1971 GMC Jimmy
2008 Hummer H3 Adventure
2003 HD Road King
vancelot69 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:54 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com