loudmouthaussie

Hi all!

My gas tank has a few pin ***** holes so needs to come out and be re- sealed. My fuel gauge on the dash doesn't work properly so i'm thinking a new sender unit while its out would be a good idea.

Anyone know if the sender units in the 73 olds clamshell wagons were the same as the GM sedans of the same era?

Any advice would be appreciated.

Thanks tom

jaunty75

Don't make any assumptions about what's wrong until you've done some simple tests. Can you be more specific when you say the gauge "doesn't work properly"? What, exactly, does it do, if anything, when the ignition is on?

There are two wires coming off the sending unit, which is located at the top of the tank on the forward side. You'll need to remove the stone shield behind the left rear wheel to get at it. (The tank is located behind the left rear fender right at the point of the filler neck.)

One of the wires goes to ground, and you should make sure that that wire is firmly connected and the connection is clean with no dirt or corrosion around it. If you find that the ground was dirty, disconnected, etc., fix the problem and then recheck the operation of the gauge. This might be all that's needed to fix it.


To test the operation of the dash gauge itself, disconnect the other wire coming off the sending unit and ground the side coming from the gauge. The wire may disconnect directly at the sending unit, or there may be a connector in the line you can pull apart. With the wire coming from the gauge grounded, turn the ignition ON and observe the gauge. It should go to E and stay there. Remove the wire from ground, and it should go F, or more likely well past it, and stay there.

If the gauge operates as described above, the gauge itself is fine. If it doesn't, check the wiring between the gauge and the rear of the car.

If everything checks, then, yes, the sending unit is the next thing to suspect.


Unfortunately, the sending unit for the Custom Cruiser is different from the one used in the 88s, and 98s, and I've never found a source for new ones. New gas tanks are available for the wagons if it turns out you need to replace it.

With EECS (Evaporative Emission Control System):

http://www.autozone.com/autozone/par...vice=420803505


Without EECS:

http://www.autozone.com/autozone/par...vice=420803505


I'm sure other vendors will have these as well.


Be advised that removing the gas tank on a clamshell station wagon is no trivial matter. It requires putting the car on lift, lowering the car onto jackstands supporting the car on the frame side rails, disconnecting the left shock absorber from the axle housing, and lowering the axle housing as far as possible without stretching the brake hose. Then pivot the tank down and out of the car. Of course, the tanks straps have to be removed as well along with the fender skirt rear mounting bracket.

To my mind, if one is going to go through this much trouble to get the old gas tank out, you might as well put in a brand new one and eliminate any chance that the repaired old tank will start leaking again after a period of time causing you to have to go through the tank removal process all over again.

If you do determine that the sending unit is causing the problem with your fuel gauge, perhaps it would be possible to clean, repair, or rebuild the unit you have.


By the way, the entire 1973 Olds Chassis Service Manual, where all of this is covered, is available over at wildaboutcars.com, which is free to join. The relevant section is pages 8-13 to 8-16.

loudmouthaussie

thanks for all that great info jaunty! a new tank to Australia would probably cost 1000 by the time it was landed so ill have this one repaired. seems like they don't make reproduction senders for wagons so yeah, ill see about getting existing one fixed up