Skyliner gas tank

[jdwilker]

Just finished installing a new gas tank in my Skyliner and what an adventure it's been. The biggest hassle has been installing the new sender unit. That piece came with a lock ring and an o-ring that plainly is too thick for the application (1/4 inch thick). There is just no way to compress that o-ring enough to lock it into place. When I looked at the original tanks o-ring, it was rounded on the bottom to fit into the groove, but the upper part was flat and much thinner than the replacement. I ended up trimming about 1/3 of the rings thickness off by mounting it on top of the lock ring and using that as a jig.  Then by using a razor knife and heating it with a torch, it cut through the rubber like butter.  The trimmed ring still had to be compressed a little, but I was able to lock it into place.  Of course, the acid test will be when I fill it with gas.  Anybody have a similar experience with this?

[RICH MUISE]

Similar, but different, lol. I can't remember (old age bad memory) exactly what the issue was, but after finding and ordering a quality fuel sender to match the ohms range of my gage, I found out it had the wrong type of mounting plate....maybe a screw-down?? I ended up morphing the new gage's inards onto the old sending unit's mounting plate, which fortunatly was still in good shape.

[BWhitmore]

I tried to use a new sending unit from a sedan on my Ranchero by bending the arm.  No luck.  I ended up having a company called John Wolf (Pennsylvania?) rebuild my original stock sending unit ($135) and they included a new O ring.  Worked great.  John Wolf advertises in Hemmings.  The price may have gone up as this was 3 years ago. 

[John Palmer]

All of the original ford gas tanks that I have worked on had a square profile O-ring.  The tank side has a curved seating area which would cause the O-ring to deform into a curved shape on that side.  I would think you could use a normal round shaped O-ring in the appropriate thickness.  Originally they were hard to get started during replacement, but the density of the rubber ring did conform.  A 1/4" high does sound a little thick.

[hiball3985]

I wasn't too happy about the original designed rubber band type and tried to find a regular O ring to fit but never found one of the right diameter and thickness. After a few tries I finally got the original one to seal, it leaked the first few times.

[clusterbuster]

Guess this is giving me a heads up on what to expect when my new tank arrives this week. How about a good grade of gas resistant sealer applied to the o-ring seal when putting it together?

[jdwilker]

I did apply a bead of gas resistant sealer with the altered o-ring - hope that helps. I'm not sure how that sealer reacts with rubber, but I figured it should add a little insurance. I originally tried to source another, better fitting o-ring, but just try to find the right one.  In the universe of o-rings, trying to find one with the correct dimensions and not being forced to buy a case of the things is nearly impossible. You'd think that job should be the responsiblity of the vendors offering a part with the "correct fit".
One other thing I wanted to mention is that even though the tank is listed as a "exact reproduction" of the original, it is not. The shape of the original is square in the lower rear part of the tank. In the replacement it is slanted at a 45 degree angle.  This does not affect its fitment in the car, but requires new, compatible straps to mount it and probably changes its capacity.

[pepfalcon]

i had the same problem with the new sender i ordered. o ring was way too thick. ended up splitting it to be able to get retainer on. have not tested it yet, but hoping for no leaks.

[clusterbuster]

My new tank arrived today and it had a rather thin cork gasket for the retainer. I don't plan on putting the tank in yet,as I need new straps and the right timing to do the job. Also ordered new strap bolts which came today. When I do the job, I will report back and tell how it went with that cork type  gasket o-ring. Seems as though some type of permatex could be used on it. Will see.

[clusterbuster]

Found this sealer that should work on my gasket and rubber o-rings that are used on any ones tank sender retainer.


Permatex? PermaShield? Fuel Resistant Gasket Dressing & Flange Sealant

[hiball3985]

Do a trial fit, one of the cheap replacement sending units I tried came with a flat thin cork gasket and when I installed the lock ring the sending unit was loose, no way it could provide a seal.