I have an 85 gs as my dd beater and fuel gauge doesn't work, so I know I can go 300 miles every fill up so I fill up- about a week ago I filled up and found a hole now so it leaks for about the first 50 miles. Bought a new (used) tank off a member and tried to install it today with no luck it will not go in- am I doing somethng wrong or are the tanks just different because they look almost identical besides the fact the 85 has a removable sending unit and the 83 does not-
I searched and found nothing any help?

 

What do you mean by will not fit?

The '82 Fuel tank I had is almost the same as the GSL-SE one I am using, the only difference is as you mentioned a removable sending unit.

Are you sure that you're using one from an 83? the SA use a different gas tank because they used a full sized spare if I remember correctly.

 

It will not go all the way up on the drivers side something is stopping it- but yes its out of an 83 I was there when it was removed I've wiggled it around into every position but it just won't fit all the way in place

 

tanks are fitted to the following years:

79-80
81-83
84-85

 

What do you mean by Fitted???

https://www.rx7club.com/build-threads-293/rising-ashes-pics-warned-812400/

I cant see any physical difference that would prevent them from being installed

 

Yeah thats what I was saying side by side they look identical cept for the sending unit but this dam thing just won't go in

 

I was not able to put an 83 tank on my old 84 GS. The tanks are slightly different. I agree with Dave on the years that are interchangeable. The top flat area where the fuel and vent lines are is wider on the 83. The 84-85 tanks are slightly taller and the fuel pickup line plate adds another 1" or so.

More pictures

84 GSLSE left 83 GSL right

 

I have not personally tried this swap but others have stated that all 81-85 models will interchange.

https://www.rx7club.com/showthread.p...light=gas+tank

 

All fuel sender units are removable.

You can remove the line assembly(Different part and location) on the SE so you can replace the sock filter inside.

 

if u have a welder fill the tank with water and weld or braze the leak just put some heat in when u emptey the water and let it sit for a day or two (slosh the heat around)

 

even the SA tanks can be used in the late model chassis if you add an 1"-1.5" spacer between the tank and chassis on the passenger side

 

Interesting. I had the same problem that 12arotary has. I couldn't get the tank to go up all the way. The top hit the body and the straps weren't even close to being long enough. If the tanks won't interchange there would have to be some difference in the 84-85 spare tire well. I have 84 and 83 parts cars. I'll take some measurements and see if I can find a difference.

 

I installed an 85 tank in my 83. It fits tight. Some BFH action would make it fit better - and thats what I plan to do when I drop it to clean and POR it.

 

I put an 85 tank into my 81 just had to take it slow and wiggle it into place
so an older tank into the 85 should work

 

just remembered the tank I took out of the 85 was originaly out of a 81 gsl so your swap should work you may need to adjust your lines a little

 

Problem solved- 83 tanks don't fit in 85's stock-ly they are different-
welding is out of the question due to the fact there are like 3 pin holes on an
area thats super rusty so I would have to remove a large portion of the top and replace it so i'd rather just replace the tank, also the walls on the inside are pealing off so no matter how many times I power wash it,or use rocks and kerosene- everything- it just gets dirty again- so i'll try to fine another thanks for the info all
Dave's response of this is correct-
tanks are fitted to the following years:

79-80
81-83
84-85

 

do you have friends or relatives from LA area who can ship it to you. I have several between SA-S3. Finding it and getting out the pile of junks may take days

 

haha thanks but there are lots of them around here I just have to look,
just nothing will beat what I paid for the one I have

 

i paid to have a rust free SE tank shipped to me from oregon. wasnt too expensive and was worth it when i opened the box. you just done see tanks that nice in ohio. if wacky will sell you one, go for it. western tanks are scarce as hens teeth!

 

I measured the distance from the left inside metal wall to the left edge of the spare tire depression, directly below the rear left speaker. 83 GSL was 15". 84 GSLSE was 14". I'll take some more measurements when I have time, but It appears the two cars I have are different.

 

Silly question but are you loosening the front (forward) long tank strap bolts about 3 inches prior to installation or are you just installing with only the Rear short strap bolts?
I took me 3 tries to figure out that the front bolts are there to provide slack in installation of the tank. I was freaking thinking that the 85' -SE tank was different than the 83' GSL tank I was replacing for Ron.
I works just fine, the sender on the GSL-SE tank is 3 prong, 83' sender is 2 prong connector.

 

yes tried that- and to put the stock tank back in it took me about three min with 8 gallons of gas in it still so that kinda puts proof on the it doesn't fit in the stock settings-
and you can get the three prong to work fine with a two prong sender

 

thats odd. i put the tank from my 84 -se into my 82 gsl with little issue

 

I believe the 81-83 tanks have a slightly wider flat area on top. That would let 84-85 tanks fit into earlier models since those tanks are slightly smaller. The problem comes when you try to bolt the wider top of the early models into the smaller area on the 84-85 bodies.

 

Yeah the Question was will an 83 GSL tank fit in an 85 GS
Answer is it doesn't without some kind of modification-
it should work the other way around