71supreme

Hey all, I have drained all the fuel and am getting ready to drop the fuel tank to inspect it, get it boiled out and replace the sending unit.


Do you have any tips on removing the tank? Signs the tank is not salvageable? stuff to beware of?


Any help would be appreciated, thanks!

pogo69

make sure to remove the ground strap under the car and wiring harness inside the trunk, use some penetrating oil on the tank straps. if by yourself a floor jack and a piece of plywood to support tank and as its lowered you have to tilt it to get the filler neck free from the frame its more awkward than heavy. if you have a telescopic snake camera you can get a good look inside of it

71supreme

Thanks Pogo! I'm hoping to get this done Friday AM. I will likely post pic's when it's out

hookem horns

Tank bolts can be rusted solid so be prepared to cut them. Spectre repop tanks are resonably priced if the old one is in bad shape.

71supreme

Thanks Hookem!


Is the tank just held in by the 2 bolts and straps? other than the wires Pogo mentioned, are there any other surprises? I'm going to take a peek under there this afternoon, but I don't think I'll have time to get under there & pull the bolts til tomorrow


Thanks!

rcorrigan5

If it's like my '68, you got it. Just another reminder, though, about the filler neck. If you just let the tank drop, you will bend the filler neck on the frame. Be careful to make sure the filler neck is clear of the frame.


Randy C.

pogo69

just the straps hold it in but dont be confused the inner part of the strap strap needs to removed about a 4'' bolt (closer to the front of the car) the rear part of the strap behind the bumper with the short bolts just retains the strap. and as said its possible that they are rusted and may need cutting. and of course you have to reach up and remove the fuel line and return line (if equipped) they are at the center of the tank just a band clamp and twisting action will remove it... watch your face in case there is gas in the line. there may be a vent hose on the upper right part of the tank that needs to be loose from the frame....once you get under and look you will see

pogo69

yes the filler neck is a pain you have to lower the front part of the tank and tilt it near vertical to get the neck out of the frame.... you may lay there and wonder ''how the hell does this come out'' but it does

droldsmorland

What others mentioned ....and get it up in the air as far as you can, A lift is preferable if you have access to one. Buy all new hardware, straps, sending unit, its o-ring and insulator pad etc...You dont want to do it twice. Some like to preserve "clear coat" on the new tanks or Blacken the original if the galvanizing is shot.
Replace the fuel line jumpers with new high quality hose designed for todays sheet gas. I like the original spring clamps verses the worm gear clamps. The worm gear clamps tend to pinch the hose and tear into it or cause a slight gap which = an air leak. Make sure both ends of the ground wire are clean and shinny. Get a replacement or make up a weather tight wire with shrink terminals. Spray the attachment points of both ends of this wire with ignition sealer after its secured to its mounts. Put a small dab of die electric grease on the positive stud before fitting the connector over it. All this will provide years of trouble free tankin!

71supreme

This is perfect, just the kind of info I was hoping for! Thanks! I probably wouldn't be asking so many questions, but it's outside I an unheated one car garage, so the less time laying on the floor scratching my head about why this thing won't come out the better.


I was going pretty good on this ol' gal, then a hospital stay and a wedding pretty much soaked up all the spare time I had in the past 2 years. It feels good to get back to it! Hopefully this time I'll get her going enough to get some driving in this summer


Thanks again guys, I really appreciate it!

pogo69

well good luck...you have my respect for dropping a gas tank outside, the middle of winter in Maine no less....you must have some ''Old Yankee blood''

halfmoontrail

It's hard to get them empty, be prepared for it to be HEAVIER than you think.
Steve

Allan R

Been there done that. Here's some pics to help you out. They're from my thread.

OEM bolts https://classicoldsmobile.com/forums...tml#post447794

The vent lines https://classicoldsmobile.com/forums...tml#post447796

More lines and clips https://classicoldsmobile.com/forums...tml#post449637

Dropping the old tank https://classicoldsmobile.com/forums...tml#post449649

Installing new tank tips https://classicoldsmobile.com/forums...tml#post591087

droldsmorland

Oh and I have to toss it out there...no open flames! So use a hack saw on the strap bolts. Even that can risk sparks. I always have a type B or BC extinguisher next to me when in garage.
Chase out the rear tank strap bolt holes (by the bumper) with a chase...not a tap. Use plenty of lube.

Olds442redberet

I wish I would have known all of these things before I dropped my fuel tank. LOL

Even now I sometimes forget stuff as I am pulling this somewhat dangerous item from a parts car.

I agree, keep a fire extinguisher close by. Maybe two.

71supreme

Thanks guys! I just typed a complete response only to see it disappear...


Some great advice here, thank you! Allan, that is an awesome post, thanks! I think if I had that much fuel to drain I would have driven it out I just had a couple gallons to empty. I bought a shake siphon from NAPA for IIRC $12 or so. too early to tell but it so far appears to work great!


I have to say, I love this board! I belong to a Subaru board to help my wife with her daily driver and they get downright uppity when I post something that already has an answer. I did a search before I posted this question, but somehow missed Allan's thread. What I like is more information always comes out of asking a question more than once.

71supreme

As far as an update, it is snowing now, so I may get out and brave the weather anyway this afternoon. The good news is, I was able to get under the car yesterday, get it up on stands, get a hydraulic jack under the tank, and get a wrench on the bolts. The bolts turn hard, but they do turn, so I hit them with penetrant, so when I do get back out there, either today or tomorrow, they should come right out.


One quick question, the tan wire is the ground wire, correct? I did get that wire disconnected.

oldcutlass

The tan wire runs to your gauge from your level sending unit.

Allan R

The ground wire is black and runs from the sender towards the front of the car where it is screwed in place by the rear foot well area. It's the only wire that comes from the fuel tank towards the front of the car (drivers side). The ground wire is only about 2 feet long.

droldsmorland

We TRY to pride ourselves here as "upper class" as our hotrods are. After all they were targeted towards the sophisticated business man back in the day. There is a few out-layers around here. You'll learn who they are quick enough. But for the most part we play well in the sand box and are always willing to help keep Olds goin.
Now if you asked about a widget and didn't provide the year, make and model well then you will see a bit "uppityness" Bad grammar is a challenge too. Then there is the infamous Cutlass vs Supreme "motor off-set" the header companies insist exists that does not. If you asked that question it would be clear you didnt search and are lazy.