SteveG

Dwayne's Garage (http://www.dwaynesgarage.norcal928.org/) has a write-up on fuel gauge reading low when full. Seems like that would be the place to start. As usual, an excellent reference for us.

Mrmerlin

And as an addendum to this thread, in the WSM it advises to soak the sender securing nut in very hot water for a few minutes this will expand it ,
then fit to the tank and tighten it with the new tank seal.
An expanded nut will tighten further and thus reduce the tendency of future leaks.

abecker

Dwayne - Followed your writeup to perform my very first brake job ever. It went flawlessly because you provided so much detail. I have the same problem with a broken seal and appreciate the time you spent to document the procedure.

GuardsRedHammerhead

I will be using the photos and procedures documented in this thread this weekend, to correct a bad seal.

Thank you for the excellent write-up.

Geza

Just changed my seal using these instructions, but I used the hot towel method to heat up the plastic nut, thus expanding it allowing for easier opening (by hand - no tool required) - I placed a wet rag in the microwave to get it extra toasty, then pressed it against the nut for a minute or so to transfer the heat - worked like a charm. One tip I thought I'd add: you can use a 1/2 drive socket extension to temporarily plug up the hose, thus preventing any residual fuel from dripping. Once plugged, I used tape on the extension to tie it off to the side, out of the way.

Radmd74

Just came across this thread. Is this the first step to check if one notices a fuel smell after filling the tank nearly full? My fuel gauge works fine. I like the hot rag for plastic nut removal. Also I assume it is good idea to disconnect the battery before starting this job to evaluate the fuel sending unit?

dr bob

First steps include a visual inspection under the tank, looking for leaks or trails in any dust that might be telltales of prior leaks. No disassembly required usually. Then look at the tank sender area for a seals leak, as described in this thread. If you are of the habit of topping off the tank into the filler neck, it's also worth a hard look at the vent hose that runs from the filler neck forward. IIRC it's 15mm "vapor" hose. If cold fuel in an overfull tank expands, liquid may find its way into this line. Know also that there's a balancing hose between the top of the main tank section and the filler neck area, so air at the top of the main section can vent to the top of the neck while filling.

There have been more than a few reports of cracking at the top of the tank, generally due to inadequate or incorrectly placed rubber pads where the tank contacts the steel tub. The straps and the saddle that cradle the tank came with foam padding too, stuff that has deteriorated to dust in many cases. Bottom line is that a tank fracture is not that rare, so you'll want to include that possibility in your potential-causes list.

Rexxus

Hiya,

I thought I had this one pegged. I have a fuel vapour smell, no gas on the floor or anything. A mech replaced a washer in the fuel filter but the smell persisted. I ran the car a few mins and followed the write up. When I lifted the white cover and smelt over the sender unit I could detect fuel. The mech says a vapour smell won’t be coming from the sending unit, it might be the filler neck? He said if the sender had a bad seal, it would leak liquid fuel not vapour. Thoughts there? It was dry, dirty, but dry. I started in on the process to check the seal but couldn’t loosen the plastic nut. I sprayed a tiny amount of WD40 on top to see if it’d work to loosen it but nada. The hose was also a MAJOR pain to remove. It can’t be pulled off by hand. It’s way too tight. I had to wiggle it down with a pair of pliers and a screw driver but I’m worried it will damage the end of the hose.

how do you properly remove a hose? What tools? Wrap the hose in a Towel and use pliers? How do you loosen this nut? I’ll try the hot towel thing.

jpitman2

Which hose do you speak of - the return line one going into the sender unit? This one is a real pain, easy to damage the end at the tank trying to ease it off using a screwdriver. I got the plastic nut off by using 2 long screwdrivers at 45degrees, levering one against the other with the tips engaged in the ridges on the cap. Being able to turn the sender can make hose removal a little easier. It helps when refitting the plastic cap to heat it in boiling water. I replaced my tank due to spinning the outlet filter threaded insert. While it was out I replaced the short return line hose - its clipped end on the steel line pulled off the pipe with hardly any effort, so I fitted the new one with jubilee clips.
jp 83 Euro S AT 57k

Broccoli

Discovered this thread after having recently filled up and parked in the garage when I smelled gas, saw it dripping and then found it sloshing about around the sender. The not funny thing is that I had filled it during the first couple of shake down runs for this very recently restored 1986.5 barn find (those times I went right from the station to the highway). WHEW and thanks Dwayne.