Seems as if the only gas tanks available for '72 Oldsmobile B/C cars are for wagons. Are gas tanks from their fellow 1972 division mates compatible? Is there an actual difference between 1972 and 1973 tanks, as the 73 version is available as well...TIA.

 

Yes, there is. On the '73 tank, the place where the sending unit attaches is an elongated hump. There is no hump on the '72 tank. My guess that the '73 tank would not fit properly into place because of this.


1972 tank from the '72 chassis service manual. The top of the tank is flat.






1973 tank from rockauto website. The chassis service manual shows the same thing, but rockauto has a better image. The raised area is circled.




I've not heard that tanks from Chevy/Buick/Pontiac of the same size cars and same year will work. I don' think they will. If you can't get yours repaired, you'll have to find a good used or, barring that, adapt something.

 

use the search thread.
71 and 72 tank are the same in Oldsmobile full size. dont know about other gm makes. 73 and up tanks have bump up on the top of the tank and use little different evap system

 

Yeap, just got my 72 tank stripped got to braze patches above the seem where it rotted out, can't find any used tanks, repops not available

 

Still researching gas tanks, looks like the Spectra GM 61A is the correct size, only question is the location of the strap slots and possible filler neck bend angles, is the 88 tank 20 gal.? this one is 25, might be thicker near the rear where as the 88 tank tapers? IDK, trying to repair mine now, with patches on the seem where it rotted, more rot on the top and sides then on the bottom! Wash you tanks regularly, clean the seam and top.
https://www.ebay.com/itm/71-72-LeSab...-/333418471968

OG tank bottom, almost perfect after stripping.

Seam rot from folded up edge,traps dirt.

Top of tank, dirt sets and accumulates water, rust as pin holes.

 

Fuel volume depends on where you live. In US gallons it's 25. In Imperial gallons (UK and Canada) it's 20. Ref: 1 US gallon = 3.78 L. 1 Imperial gallong = 4.52 L
The Spectra Premium products are really good quality. I bought one for my car and it fits like a glove. The tank strap 'slots' lined up perfectly. No reason to think these ones won't either.

 

You bought the spectra GM61A and installed it in an 71-72 Delta 88? Its specified for a Buick but looks and measures similar to my stock 88 tank, figured it MAY work, can you elaborate on your tank/car fitment? Thanks

 

Allan,
I purchased the Spectra Premium GM34R tank for my 72 Cutlass S, engine VIN "M" (4bbl, dual exh). Is that the same tank you used? I'm having a problem with fit. The tank mounts up well to the trunk floor, straps, etc.. BUT the filler neck is in contact with the horizontal frame cross-member which is just forward of the license plate and bumper. It's putting upward pressure on the filler neck. I contacted Spectra about it, but haven't heard back yet. If I leave it like that, I can predict that eventually the solder job joining the neck to the tank is going to fail. Apparently you didn't have this problem(?). If they don't give me some acceptable course of action, I'm submitting a warranty claim for defective workmanship.
Barry Griffin

 

Hi Barry, I replied to your other post. Can you post a picture of the way the tank is mounted and the clearance issue? And yes, I used the GM34R tank. I picked it up in person at NAPA and inspected it before accepting delivery. I couldn't see any issues and it was extremely well packaged. I'm surprised your tank doesn't fit.
One other thing I would ask. Has your car been in any rear end collisions that could have affected the rear frame cross member? Those cross members aren't all that strong and could be subject to damage, however slight.Just a thought.

 

Allan, Thanks for your reply. I'll attach some photos. I am the original owner of the car, I ordered it from a dealer in Michigan in 1971 and picked it up in Sept 1971. Therefore I can verify that the car has never had rear end damage (or any other body damage) which would have moved the rear cross-member. That cross-member is factory welded in place as part of the frame, and not messed with during a restoration.

Reading about other members having their new tanks damaged during shipping - that certainly is a possibility in my case. When I received it, the body was seemingly well packaged, but not the filler neck - see attached photos taken when it was received.

I can see 2 possibilities for my fit problem: (1) defective workmanship by Spectra, and (2) slight damage during shipment, bent so little that I didn't notice it prior to installation. Looking at these as-received pix now, I see on pix #3 that the virtually unprotected filler neck has some damage to the wrapping plastic right at the end of the neck on the side of the neck that faces upward when installed. This corresponds nicely to my problem, which is that the filler neck has been displaced downward causing it to hit the cross-member. And a knick can be seen on the top of the filler neck under the fuel cap.

I will contact Spectra and see what they say about me bending it back upward, or if that will break the solder joint and/or void the 3 year warranty. If that fails, I'll see if Autozone will do anything about the apparent shipping damage discovered 10 months after I received it.

Another topic: Sun visor supports. I got some aftermarket ones from OldsParts.com. They are made in Taiwan. They look real pretty. But massive turning force on the clamping screw will not make it clamp down sufficiently on the visor pin, so the visor just flops around. And the screw head actually broke from the screwing force I applied. OldsParts has offered to refund my money. I put the original pitted ugly OEM supports back in and they work fine. Any idea how to find usable reproductions of those supports (or preferably OEM ones)? All the ones on Ebay seem to be Chinese, and the ones from the usual classic car parts suppliers are either Chinese or Taiwanese.

Barry

 

Barry, your box shows the tank is GM 34B not GM 34R. Is that something to consider for your fitment?

 

Allan, True - I should not have attached that photo. That caused me some heartburn when it was delivered. But look at the other photo with the 'Trugrade' sticker on it - it shows part number GM34R. Spectra website says GM34R has 3 vents, and GM34B has 2 vents. My OEM tank had 3 vents, and the new tank has 3 vents, so it's definitely not a GM34B. GM34B was used on various 68-70 Buick & Chevy models.

My guess is that the packaging is done by the seller and not by the manufacturer, hence the different packaging sent to end users. 'Trugrade' is apparently a trademark of Autozone or one of their suppliers - if you go to their website and look up 'GM34R' it pops up as a 'Trugrade' tank there is NO MENTION of SPECTRA PREMIUM.

Along with the virtually unprotected filler neck, 'GM34B' just another sign of packaging carelessness (and degradation of society IMO). Another sign - the 40+ defects I found on my car after I got it back from a 2.5 year restoration from Precision Restorations in St Louis - I'm still fixing their ridiculously obvious mechanical errors 2 years later (wonderful paint job though). On the plus side, at least they did honor their 6-month warranty and paid 2 local shops about $6k to fix most of their errors. I'm dealing with what's left. Now I'm ultra paranoid about who touches my car.

Barry

 

Final update: I think it's fixed.

I called Spectra Premium this morning and they basically said to try bending the filler neck up to the correct position, knowing that the solder joint might break.

So I did. See attached pix of my setup and finished product. I wedged a piece of wood on top of the filler neck base to help relieve any stress on the solder joint. Then used wood and a floor jack to move the end of the filler neck up until the desired clearance to the frame was achieved.

I think it's all good. Will know for sure after I fill up with gas and check for leaks.

Barry