Porsche Parts Catalog Porsche Accessories Catalog Porsche Technical Articles Porsche Tech Forums
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Gas Tank Removal
Bookmark and Share

Pelican Technical Article:

Gas Tank Removal

Brian Kumamoto


4 hours4 hrs






Metric socket and metric wrench set, 8mm & 10mm sockets, floor jack, jack stands, wheel chocks, safety glasses, torque wrench, flathead screwdriver, Phillips screwdriver, hair dryer

Applicable Models:

Porsche 914 (1970-76)

Parts Required:

POR-15 fuel tank treatment (for restoring existing fuel tank), POR-15 black paint

Performance Gain:

A fuel tank that won't leak that will also help keep your fuel clean

Complementary Modification:

Replace the center tunnel fuel lines and flexible fuel lines
As our 914's age, leaking gas tanks are becoming increasingly common. These leaks can develop from the inside, or can be caused by rust and abrasion on the outside, as was the case with my car. Fortunately removing and repairing the tank is an easy task.

(This is the procedure used on my 1974 2.0. There may be slight differences between various years and models, but the procedure is essentially the same).

Begin by disconnecting any vapor lines which run out from the expansion chamber, which sits on top of the tank.  Next, remove the expansion chamber itself by taking out the 8mm bolts which surround the fuel tank filler on your car.  There is also a 10mm bolt holding the expansion chamber on.

Simply lift the expansion chamber from the top of the tank, and set it aside.  You will then see the connector for the fuel tank sender, which you can simply unplug. Next remove the screw which holds the gas tank-retaining strap together. Spread the restraining straps out to the side so that you can lift the gas tank out.

Before beginning the process, you should run the tank down as low as you can.  You don't need need to take it too low (I have removed it with as much as a quarter tank left), but the less gas there is in it, the easier it will be to lift.

You can then begin lifting the tank out. First, lift the tank just enough to remove each of the rubber blocks on the sides of the tank. These are there to hold the tank in place and isolate it from excessive vibration.

Once the blocks are removed, lift the passenger's side of the gas tank up as high as you can. The 2 fuel lines run out of the bottom. The original lines are fairly short, and may be held on by non-reusable clips. Therefore, simply cut the lines (it's a good idea to use new ones anyway), and lift the tank out, keeping it lifted to prevent excess fuel from leaking from the tank.

When the tank is out, it is easy to simply pour, from the inlet and outlet lines, the fuel into and approved gas storage container. Fortunately, the 914 tank is very simple, and easy to strip down. The fuel level sender simply unbolts from the top. The screen inside the tank will come out when you unbolt the 2 short metal lines, which run out from the bottom of the tank. Once these 3 items are removed, the tank is ready for treatment, and you will not need to worry about clogging any internal lines, filter screens, etc.

There several gas tank treatments on the market, but I recommend the POR-15 treatment (1-800-45-por15).

POR-15 sells a complete kit, which includes a heavy duty cleaner, a metal etcher and the actual sealer, along with exact instructions; essentially, the tank should first be flushed out with water. Then, firmly tape all openings except for the top and mix in one quart of the cleaner with one quart of hot water. Tape upt he top and slosh the solution around. It should sit in the tank for 24 hours, being shaken occasionally to coat the entire interior.

If the tank is really dirty, the process can be repeated, but probably will not be necessary. Next, rinse the tank out and reseal all the openings, pour the itching chemical in, and reseal all the openings. This needs to be agitated occasionally, for between ' hour and 24 hours. I let mine soak for about 2 hours.

Next the tank should be rinsed again with water, and left to dry. I used a hair dryer to help speed the process.

The tank opening should then be retaped and the sealer poured in. Simply rotate the tank around until all areas have been coated, and drain the sealant. The sealer needs to drain for at least 24 hours before using the tank.

I also treated the outside of the tank (the bottom half only) with POR-15 black paint. I then painted the entire trunk with Wurth matt black paint for a factory appearance. Once the tank is dry the inlet and outlet lines can be screwed back in, along with the sender unit. The fuel lines should be replaced with new line, abort 2 feet long.  Using longer lines is nice because it allows you in the future to lift the tank up high enough to reach underneath and unscrew the hose clamps to detach the tank, instead of cutting the lines.  Be careful however, not to use lines that are too long or they will get crimped when you put the tank in blocking fuel flow. You only want them long enough to give you access.

Drop the tank in, connect the new lines, center the tank with the rubber blocks, reconnect the fuel sender, screw the expansion chamber back on (don't forget the rubber gasket!), and reconnect any vapor lines. Pour only new gas in (you don't want any left over crap from your old tank in there), and you're ready to go.  Make sure that you drop off the old gas at your recycling center.  Most places that take used oil will also take old gas.

NOTES: Some people recommend removing the front trunk lid. This would certainly give you more room, but it is not really necessary. Some people also recommend removing the steering rack cover underneath the car, but I don't think this one is necessary either, as all of the work I have described is done from above the car. Finally, make sure you do this in an area free from sparks or other source of ignition, as you will be working with an open tank of gasoline.  To be safe, it is also not a bad idea to disconnect the battery.

Bookmark and Share
Comments and Suggestions:
keith 22 Comments: If you are using 2 ft of fuel line how do you keep it from crimping? Do I need someone to guide the line from underneath at the access hole? I'm working on a 74 914 2.0 42k I've tried to make the connections from the access hole...very difficult
May 30, 2016
  Followup from the Pelican Staff: I haven't done this repair, so I can't give an exact dimension. It is described as needing two feet of line, then it sounds like trimming is needed to get the right length, without having it crimp. - Nick at Pelican Parts  
Joseph McLellan Comments: Found it!! Suction is the centre of the bowl furthest from the seam, rear of the car it's very clear on earlier models since the connections are clearly different sizes. 75 and 76 are the same that can lead to confusion. http://www.pelicanparts.com/914/technical_specs/914_18FI_diag.htm
May 14, 2016
  Followup from the Pelican Staff: Thanks for sharing your installation process and experience. These type of comments add so much to the Pelican tech community.
- Nick at Pelican Parts
Joseph McLellan Comments: Hi Nick, I've taken several photos and that's the best I can do on the inside. If I back up more the camera will focus on the filler. Fortunately the flash on my phone is 1/2 from the lense. You can see that both connections are in the bowl the one I've attached a photo of the outside and if you look closely the centre connection the one furthest from the seam has an internal fitting. Possibly a check valve? I doesn't make sense if both are isolated in the bowl. The tank won't drain all the way to the bottom if that's the case. Correct me if I'm wrong, the bowl is designed to prevent warm returned fuel to go directly back to suction. The fitting could be a plug isolating it from the bowl?
May 14, 2016
  Followup from the Pelican Staff: the bowl is to stop slosh. The large line is for the feed, small is the return. Does that sound right? - Nick at Pelican Parts  
Joseph McLellan Comments: I have the same concern as Gene. Which one is the suction/return? Front or rear not left or right... More simply put, the one closer to the seam? I've attached a photo of the inside.
May 9, 2016
  Followup from the Pelican Staff: the return would not feed the bowl. I would need to see a larger photo of the parts to offer more insight. Can you back up a bit and retake the photo. - Nick at Pelican Parts  
Amphicar770 Comments: Just removed my tank. In terms of removing fuel, I did it the old fashioned way with a siphon hose to a fuel can. Did notice that the one line was crimped and whoever relocated the pump did not use proper hose clamps or modern hose.

My tank does have some rust inside but no holes. I think I will just clean it out with oxalic acid or evaporust and let it be. I've heard too many stories of the Por-15 and similar treatments starting to peel or flake after a few years causing all sorts of a mess. Obviously, if your tank is leaking or has pinholes then some sort of salami is needed. I am surprised that there are no new reproduction tanks available for the 914.
January 16, 2016
  Followup from the Pelican Staff: Thanks for the additional info and feedback. We appreciate it.
- Nick at Pelican Parts
Karmann72 Comments: I have a 1974 with a 1.8.
I can't see where the charcoal canister is supposed to be located.
Vin # 4742917441
November 2, 2015
  Followup from the Pelican Staff: If I remember correctly, it is mounted to the left side of the tank, right corner of your image. - Nick at Pelican Parts  
t-bird Comments: I have had problems with carbs, now as I look at my tank...no wonder, full of stuff. Car sat for about 20 years. I thank you for the info, most of the work I have already accomplished, just did not know if I needed to go to the bottom and you said no. Will let you know how this comes along.
October 12, 2015
  Followup from the Pelican Staff: Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
RON Comments: Did a a kz1000. Rust tank ,it turned out just fine . It's been 8 Years since I decided to do my 1976 914 2 liter it because of medial problems had to wait Several years to get back to my little projects you will hear from me in the future .Always did like your informative articles.
August 21, 2014
  Followup from the Pelican Staff: Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
Tom Comments: Follow up comment to Bram in 2013....
Concerning fuel - the new fuel with the ethanol additive begins to evaporate and turn to "water" after about 30 days and will play havoc with your engine - causing poor idle, surging, etc. ps - this additive put in a gas can for your lawn mover, blower, etc will eventually damage these machines - I have found regular gas with no ethanol at my local hard ware store - also going to an airport to get fuel is a great idea There is currently NO additive that addresses this problem except using ethanol free gas.
August 21, 2014
  Followup from the Pelican Staff: Thanks for the additional info. We appreciate it.
- Nick at Pelican Parts
RC Comments: No. It is a metal pipe stub 2 - 3 inches at about 20 degree angle facing the driver side and a little less than half an inch inner diameter. R.C.
November 20, 2013
  Followup from the Pelican Staff: I think you are referring to the vent hose. It should run through a hole in the metal panel behind the tank up toward the filler neck. - Nick at Pelican Parts  
RC Comments: After replacing my 912 fuel tank with a new one, I forget where the small outlet on the TOP of the tank is supposed to be connected. Any suggestion? Thanks
November 5, 2013
  Followup from the Pelican Staff: Is it a small vacuum hose? I think it connected somewhere near the driver side firewall. - Nick at Pelican Parts  
bram Comments: I am the first owner of a 1973 Porsche 914 1.7L. It was sitting in the garage for 20 years. When leaded gas was no longer available I started using regular unleaded gas with lead substitute additive. The mechanic where I got most of the work done to get it going again said I could use regular unleaded gas with no lead substitute additive or aviation fuel, may be because he also operates and maintains helicopters. My question is: which is the best gas to use for keeping engine internals clean and crank good also.
January 12, 2013
  Followup from the Pelican Staff: I would use a name brand gas and a good octane grade. - Nick at Pelican Parts  
Aquazulu Comments: Thanks for the point to POR-15 flush and sealer.. I resaerched it as a rust inhibitor on ebay, liked the product but I did not know they had a tank sealer.. I am rebuilding a 1986 911 after a couple of years mothball, was planning to replace the tank, but now looking for ways to refurbish the old one.. Thanks. 1-800-45-por15.
December 25, 2010
  Followup from the Pelican Staff: Thanks for the additional info. We appreciate it. - Nick at Pelican Parts  
Shindog Comments: It's a good idea to replace with little thicker outside diameter fuel line. I replaced mine with an inexpensive fuel line from the local auto parts store and had the crimping problem mentioned. I have had to replace with a thicker OD hose to stop the crimping.
January 25, 2010
  Followup from the Pelican Staff: Thanks for the additional info. We appreciate it. - Nick at Pelican Parts  
Ken Comments: "Simply cut the lines,and lift the tank out, keeping it lifted to prevent excess fuel from leaking from the tank". I;m lost...how do you cut the fuel line and not have a shower of gas raining down as you lift the tank?
September 9, 2009
  Followup from the Pelican Staff: You have to use a fuel line crimping tool above where you cut the hose. A heavy duty medical hemostat works too. - Nick at Pelican Parts  
Gene Comments: Recently removed gas tank, cleaned, and added new hoses & clamps. Stock FI is gone, to be replaced with carbs. I don't want to get into the carb vs. FI thing, so my question is: How to tell the inlet from the outlet on the wall where the short tubes are, and does it matter which tube on the tank is used with the hose from the fuel pump/filter going to engine? What do most people do with the other tube on the tank & the wall?? Do I need a return line? TIA.....Gene
July 3, 2009
  Followup from the Pelican Staff: Good questions. For a carburetor installation, you don't need a return line. One of the lines coming from the tank has a built-in screen inside the tank - this is the one that you want to use as your supply line. Install the pump in the engine compartment, below the battery area, and you should be okay. Vapor lock and other problems like that don't really apply to low pressure fuel pump systems. I recommend using a Carter pump - it's about $80 or so. Make sure that you mount it correctly with rubber mounts or it will be loud as all heck. As for determining which line is which, I forget whether the one on the right or the left is the supply line. You can trace back the lines from the pump you have on the car now and see, or ask someone in our forums to do it for you. The lines in my 914 (now a six conversion) were replaced a long time ago. Hope this helps! - Wayne at Pelican Parts  

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    


[Home] [Customer Service] [Shopping Cart] [Project/Wish List]
  [Privacy Statement]  [Contact Us] [About Us] [Shipping] [Careers]

Copyright © Pelican Parts Inc. -    DMCA Registered Agent Contact Page

Page last updated: Wed 10/26/2016 02:14:58 AM