Topic: 1980 Fuel Gauge Calibrating
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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Let me see if I have this straight and correct me if I'm wrong.
'77 and earlier vettes had a bladder that was pliable?? (I've never looked in one)
'78-'82 vettes had a thick hard plastic liner. More like how modern plastic fuel tanks are today. (I've looked in a few of these tanks)
And no... '82 Cross Fire Injected vette tanks do not have a baffle in them for the in-tank fuel pump. This I know for fact.
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Vette(s): 1981 Coupe, Guards Red, Edelbrock Performer Intake, Holley Street Avenger Carb, Hooker Headers/Side pipes, Richmond Super T-10 4 Speed, TruSpoke Wire Wheels
Sarge81 said: Let me see if I have this straight and correct me if I'm wrong.
'77 and earlier vettes had a bladder that was pliable?? (I've never looked in one)
'78-'82 vettes had a thick hard plastic liner. More like how modern plastic fuel tanks are today. (I've looked in a few of these tanks)
And no... '82 Cross Fire Injected vette tanks do not have a baffle in them for the in-tank fuel pump. This I know for fact.
I had wanted to ask someone knowledgeable about this because when I read Knudsen's "Star Spangled Sports Car", he had said in there that the 78-82's had a hard liner and that 77 was the last year of a bladder. I was confused/surpised because I had always heard that all C3's had a bladder, and I have never had my tank off/out to check. I guess mine works the opposite since it was my understanding the tanks were 24 gallons, but when mine reads empty the most I have ever put in it is about 18 gallons and I always thought 6 gallons was a lot to have for "reserve".
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rastafford3164 said:
I was confused/surprised because I had always heard that all C3's had a bladder, and I have never had my tank off/out to check. I guess mine works the opposite since it was my understanding the tanks were 24 gallons, but when mine reads empty the most I have ever put in it is about 18 gallons and I always thought 6 gallons was a lot to have for "reserve".
I was confused/surprised because I had always heard that all C3's had a bladder, and I have never had my tank off/out to check. I guess mine works the opposite since it was my understanding the tanks were 24 gallons, but when mine reads empty the most I have ever put in it is about 18 gallons and I always thought 6 gallons was a lot to have for "reserve".
There were NO bladders or liners in the tanks until the '75 model. Earlier cars were nuttin but steel. The tanks are listed as 20 gallon for most years, but the '68-'74 cars have a filler tube extended down into the tank, that will keep you from being able to put any more than 18 gal in them. The '75-'77 cars had a little less fuel capacity due to the bladder taking up space. The '78-'82 cars had different tanks to start with, and I think most of those will hold 20 gal when totally empty...not 100% sure on those.
The '75-'77 bladders can be removed fairly easily thru the filler neck hole, once the neck/sending unit has been removed. The later cars with the less flexible liners can be removed, but not very easily.....usually not worth the effort. Even the rigid type liners can deform over time, and cause problems.
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Hello all. I just bought a 80 vette that needs a lot. First thing to fix is the gas gauge:) then speedo. I've read this post and I'm not sure what to do next. When I disconnect the ground to the sending unit the gauge goes past full. As soon as I reconnect it drops to around a quarter full but nothing else. There is probably 15 gal in the tank and no change. I have a limited budget and a little knowledge(which is dangerous) so I just don't want to throw money at parts wishing it works. I'm looking for any and all advice I can get. Thanks
Use your average mpg and the capacity of the tank. That should tell you how far you can go on a tank. Just reset your trip odometer.
Unfortunately the speedometer doesn't work either. That is project number two after I get gas gauge working.
Car pic
(modified large image to link-aapple)
|UPDATED|7/20/2015 4:21:11 AM (AZT)|/UPDATED|
Car pic
(modified large image to link-aapple)
|UPDATED|7/20/2015 4:21:11 AM (AZT)|/UPDATED|
Ground the wire to the sending unit and see if it reads empty. If so your 80 either has a bad ground from the sending unit in the tank, or a bad sending unit. if not, it's back up to the dash gauge or a bad connection between the two.
|UPDATED|7/20/2015 6:00:18 AM (AZT)|/UPDATED|
|UPDATED|7/20/2015 6:00:18 AM (AZT)|/UPDATED|
OK ...... it may be Aliens but I have to tell this story.....
I have been
having a problem with my 1980 fuel gauge for 5-6 years.....
ebo
The gauge would not go to full when topped off, went to 3/4 or less. When fuel burned past that, it would read correct and the low fuel light would come on when at that point in the red on the dash gauge. I removed wires as both Joel and Ken have instructed and still did not correct. Spring of 2014 I removed and replaced fuel tank sender, left lots of blood around tank opening for future DNA testing if needed. Still no change.
This spring 2015 I purchased a new fuel gauge and was ready to replace but did not find time before gathering.
OK here is the Aliens part.....We have a local quick stop fuel station that offers non ethanol fuel. I started running that in the vette last month. I filled the car 2 weeks before the gathering and it sat until that trip.
As we are on our way I noticed the gauge is reading full again, during the gathering there was no non ethanol fuel to find..... the gauge would not go all the way to full but very close. I came home close to empty and filled with the non ethanol and its back to the full mark on gauge.......doo doo doo doo......doo doo doo doo.......you explain that one to me......Kyster......Adams Apple........??
ebo
eboin Forum: C3 Fuel, Emission Control, and Exhaust Systems
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