Series 2 Fuel Tank seepage when over filled

John Goldie · May 16, 2016

Greetings - (Series 2A 88 NAS 1969)
Noted that when the tank got over filled, gas leaked from the top seam of the tank and under the truck perhaps 0.5 gal. I guess it did that until the gas in the filler drained down enough below the seam.... I think the vent in a closed system, so I dont think it back flowed from that. Inspected the filler pipe / vent pipe and all is dry there, lifted the plate under the passenger seat and can see some seepage marks around the top seam. Is this normal, or time for a new tank? Looking for advise and or any removal tips. While I was in there, I did clean up the sender unit contact and the fuel gage is reading better now. Thanks in advance.
John G
San Carlos CA

SpringDon · May 16, 2016

If it's not leaking from the sender or vent gasket then it's time for a new tank or tank sealer.
There are a couple of people here who will braze patches on to classic car tanks, don't know if you have that over there.

John S · May 16, 2016

The location and shape of the fuel tank is a design flaw in series landies. Mud, grit, water and salt accumulate at the back and inner side of the tank on top of the metal seam. Unless periodically blasted and scraped clean it leads to corrosion and leaking tanks. Even with ordinary road use there will be serious build up of crud in this area over time. Best way is access from the top and use a long screwdriver to scrape the crud out and then wash and scrub with wire brush etc. to get it back to bare metal. Red oxide and then a Hammerite or similar top coat of paint will keep it at bay. If your are in there anyway its a good time to do likewise to that part of the main chassis as well if it's showing rust/ distress...and greasing the hand brake linkages!

kommer2013 · May 17, 2016

John S said:
The location and shape of the fuel tank is a design flaw in series landies. Mud, grit, water and salt accumulate at the back and inner side of the tank on top of the metal seam. Unless periodically blasted and scraped clean it leads to corrosion and leaking tanks. Even with ordinary road use there will be serious build up of crud in this area over time. Best way is access from the top and use a long screwdriver to scrape the crud out and then wash and scrub with wire brush etc. to get it back to bare metal. Red oxide and then a Hammerite or similar top coat of paint will keep it at bay. If your are in there anyway its a good time to do likewise to that part of the main chassis as well if it's showing rust/ distress...and greasing the hand brake linkages!

i made up mud guard

John Goldie · May 18, 2016

Thanks for the feedback, I inspected it some more and not sure if it is the seems and now suspect the sendor or feed gasket are the leak as suggested

..... Will park on a slope to help push the gas up (perhaps top off a tad too) and inspect again with the under seat plate off to see if that is indeed the source of the stream which then spills down the sides of the tank. Will also clean up the tank as suggested. She is a bit of a mystery - would be happy of old dryed gaskets vs new tank - thank you all for the advise and feedback. Will post the final outcome.

John S · May 18, 2016

A new fuel pump isn't expensive.

John Goldie · Jul 5, 2016

Greetings - Tank issues resolved, just wanted to share the leak source. As suggested above (thanks!) the cork gasket on the draw line was leaking and allowing gas either sloshing around or if over-filled into the large bore fill pipe to have pressure to run out while it emptied down to that point. Also replaced the sender round gasket, lock washers and fill and vent pipes at the same time. Back on the road again. Many thanks for all the advise.

John G

Series 2 Fuel Tank seepage when over filled

John Goldie

Member

SpringDon

Well-Known Member

John S

Well-Known Member

kommer2013

Active Member

John Goldie

Member

John S

Well-Known Member

John Goldie

Member

Similar threads