ixfxi
04-18-2017, 10:55 PM
Repairing the plastic S14 fuel tank has been a topic that has come up time and time again over the years here on Zilvia and various other forums. Being that I've always owned an S13 and other vehicles with steel tanks, I've never had the need to repair a plastic tank until my recent acquisition of an S14. If money is no issue I highly advise purchasing a new tank. In my case, this restoration project is so vast that I am doing my best to keep a practical budget in order to keep costs from spiraling out of control.
If your tank has a large split it will most likely need to be replaced. My tank had some very small pinhole leaks in the front LH corner, right along the factory plastic welded seam.
For all you novices, this is no easy fix and you will need to go through the extensive procedure of dropping the subframe, emptying the tank and then dropping it. I advise that the tank MUST be empty before attempting this fix.
Once you have emptied the tank, wash it out with water - inside and out. Dry it off and then seal off the tank as best as possible as you will need to pressure test it with compressed air and use soapy water and a brush to locate the leak(s). Locate the leaks and mark them with chalk. The next step is to use a heat gun with an exacto flat razor. I used the flat razor as a putty knife and using direct heat from the heat gun, managed to heat and rework the plastic tank. It took multiple attempts, but eventually I managed to close up and cover all the pin holes. There must have been about 5-6 very small holes, but that was enough for the fuel to seep out of. Here are some photos of the tank and the repaired area. You can see how the OEM seam has been flattened and smoothed.
http://www.clearcorners.com/temp/fueltankrepair1.jpg
http://www.clearcorners.com/temp/fueltankrepair2.jpg
http://www.clearcorners.com/temp/fueltankrepair3.jpg
As of today, new tanks list at $650. Most of the fuel related parts are discontinued. I would highly advise buying a new tank. But, if you are on a tight budget and replacing the tank is NOT an option, hopefully this fix will help you.
Note: I pressure tested the tank and it checked out A-OK.
If your tank has a large split it will most likely need to be replaced. My tank had some very small pinhole leaks in the front LH corner, right along the factory plastic welded seam.
For all you novices, this is no easy fix and you will need to go through the extensive procedure of dropping the subframe, emptying the tank and then dropping it. I advise that the tank MUST be empty before attempting this fix.
Once you have emptied the tank, wash it out with water - inside and out. Dry it off and then seal off the tank as best as possible as you will need to pressure test it with compressed air and use soapy water and a brush to locate the leak(s). Locate the leaks and mark them with chalk. The next step is to use a heat gun with an exacto flat razor. I used the flat razor as a putty knife and using direct heat from the heat gun, managed to heat and rework the plastic tank. It took multiple attempts, but eventually I managed to close up and cover all the pin holes. There must have been about 5-6 very small holes, but that was enough for the fuel to seep out of. Here are some photos of the tank and the repaired area. You can see how the OEM seam has been flattened and smoothed.
http://www.clearcorners.com/temp/fueltankrepair1.jpg
http://www.clearcorners.com/temp/fueltankrepair2.jpg
http://www.clearcorners.com/temp/fueltankrepair3.jpg
As of today, new tanks list at $650. Most of the fuel related parts are discontinued. I would highly advise buying a new tank. But, if you are on a tight budget and replacing the tank is NOT an option, hopefully this fix will help you.
Note: I pressure tested the tank and it checked out A-OK.