Ok, so I need to replace my fuel sender unit in my 90 240 Wagon. I have the parts I need however I just got off with my dad who is the GM at a Volvo dealership and told him what I was going to do. He said that I would be lucky if I didn't come away from the experience with a new tank on the car because of the rust that is usually found in a 14 year old car which lived its whole life in Vermont.
Well I'm in Orlando, FL now and I drive 40 min to work each way and I could really use a gas gauge so I need to get this done. Anybody have experience with this kind of thing? And if I do need a new tank, where should I get it and how difficult are they to install.

Tom
Orlando, FL
1990 245 185K

Just did one of these in a 1990 wagon. Typical rust (Connecticut). The sender totally rotted out at the top. The nut was very rusty too but did come out.
There is a special spanner tool for the nut. I've always managed to do this using a punch or chisel and a hammer.
Soak everything with PB Blaster, and wipe up the loose dirt- don't let rust and crud fall in the tank. On the one I just did, two of the steel lines broke right off the sender- a fuel disaster waiting to happen.

Buy the sender, a new intank pump, the sock filter, a new o-ring and a new nut. Get a few sizes of hose clamps as well- the old ones are guaranteed to be useless and it's helpful to just have some handy. You need to reuse the plastic housing around the old intank pump, or at least I did on the one I just replaced.

The other cable through there, a grey cable, is the speedometer sensor to the rear axle- it'll just be in the way as you service this, and you can unplug it as needed for access.

Hope this helps- good luck!
--
Rob Bareiss, New London CT ::: '87 244DL/M47- 234K, '82 245T/M46-182K, '89 244DL/AW70- 212K Not too distant past: 86 244DL 215K, 87 244DL 239K, 88 744GLE 233K, 88 244GL 147K, 91 244 183K

And please do your tapping around the tank with something made of brass or copper etc. No sparks is a good thing.
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'94 940 150k, '86 240 170k, '72 142 KIA, '70 144 KIA, '69 144 RIP

And sniff before sucking dirt with a vac.

OK so I did my 240 '89 which was born and raised in the cold salty canadian north....

New sending unit, pre-pump, lock ring for sure, small hose, sock...

LOTS of release-all, WD40, liquid wrench, tapping, tapping, tapping, tapping...
I tapped for exactly one hour. It was slow but steady and eventually got out.

The tank top was perfectly rust-free. The only parts that had rust were the lock ring and the sending unit top plate. Consequently those got replaced so everything was like new afterwards.

What you need it patience, patience, tapping, tapping, round and round to not buckle the lock ring. After scraping the chunks of rust off, a vacuum is used to take away the rust so it does not fall into the tank afterwards.

PATIENCE and it will be long, hard, but well done.

Greg Mustang

The sending unit is also the tank's top cover plate, which includes the terminals for all electrical and hoses going in and out. If you don't replace the sender, eventually one or more of those terminals/connectors will fail, and you'll have to do the job anyway.

I'd replace the in-tank fuel pump at the same time. Getting in there is no picnic, but once you're there, give yourself a new pump. The price is relatively low. If the old one fails, the car will likely keep running, relying mainly on the main pump (outside the tank), but this strains the main pump, leading to its premature failure - and the main pump is much more expensive.

i've never seen cars from vermont before but the rusty 1s i've seen took a lot of patience. spray the top of the sender with wd40 or something a few days and times before starting. tap at it a few times to get things loose. buy the lock ring and a new oring and keep the pounding limited to just the ring, not the tank. good luck, chuck.