was my gas tank switched?

Topic: was my gas tank switched? (Read 1758 times) previous topic - next topic

was my gas tank switched?

November 03, 2005, 03:35:35 PM

i just filled my cougar up full of gas. a rarety for me bu i needed to for work next week. anyway, it took 14.5 gallons and i had bout 2 or 3 left in the tank when i filled it. Now on the cool cats web site it says i should have a 20 gallon tank. what gives? also its a 84 with the 5.0. so shouldn't it be a 20 gallon tank? insted of possibly a 18 gallon?

was my gas tank switched?

Reply #1 – November 03, 2005, 03:41:04 PM

My guess is you really had four or five gallons left over. :)

was my gas tank switched?

Reply #2 – November 03, 2005, 03:43:05 PM

i must have because it was actually on the line before empty. and i know when it reads empty there is about 2 gallons left in the tank. so it is possibule i had that mutch left in it.

was my gas tank switched?

Reply #3 – November 03, 2005, 03:48:12 PM

There is almost always more gas left in the tank than what your gauge indicates. When the needle is physically on the E, you should have 4-5 gallons left in the tank. That's your early warning system...after that you're on your own.

was my gas tank switched?

Reply #4 – November 03, 2005, 04:12:26 PM

I dont think that is entirely true. The other day I ran out of gas and my digital gauge said 2 gals left. I had pushed it that far before, but apparently I was lucky.

was my gas tank switched?

Reply #5 – November 03, 2005, 04:21:30 PM

OK, digital is a totally different ballgame. The factory digital gauges show a representation of something, not the actual value. In other words, two bars is not equivalent to 4 gallons, or any set amount for that matter. It's just an indication that you have little gas left in the tank. How much? Take a guess...that is why the digital cluster is so frustrating. It is accurate for the speedo but that's it. Everything else is merely representational.

was my gas tank switched?

Reply #6 – November 03, 2005, 04:28:29 PM

I've run my car about half a notch (if it existed) below the E and can still only get ~15.5gallons in. Never seen it take anywhere near 16+ gallons at the pump.

Does the tripminder know pretty accurately how much there is? Tempted to pick one up just for this

was my gas tank switched?

Reply #7 – November 03, 2005, 06:12:57 PM

I've gone over a 1/4 past E and only put in just over 17 gallons in my '85 Cougar. It has some, eerrr, sending unit issues methinks.

was my gas tank switched?

Reply #8 – November 03, 2005, 08:28:10 PM

Before i repaired the gas tank, the "Low Fuel" Light came when i had at least 12 liters. After , the los fuel light come on when i had only Five liters. One time i ran out of gas `cause i need fast transportation and i took the car, no time to get to the gas station...Who cares, my "low fuel light didn`t come".... ten minutes later the car dies, luckily that was in the city....

was my gas tank switched?

Reply #9 – November 03, 2005, 09:14:05 PM

Quote from: EricCoolCats

OK, digital is a totally different ballgame. The factory digital gauges show a representation of something, not the actual value. In other words, two bars is not equivalent to 4 gallons, or any set amount for that matter. It's just an indication that you have little gas left in the tank. How much? Take a guess...that is why the digital cluster is so frustrating. It is accurate for the speedo but that's it. Everything else is merely representational.

Then I must have the most rarest digital gauges of all. I've run my tank down pretty low, like a gallon maybe 2 left, and the gauge ended up being almost dead on. Granted my gauge show's E when I hit 2 gallons or less, but it's still pretty accurate IMO.

was my gas tank switched?

Reply #10 – November 04, 2005, 12:41:27 AM

my digital cluster shows gallons and also has a gauge after it gets to 2 gals it goes flashing "E" havent ran out of gas yet

(knock on wood)

takes about 16.5-17 gal to fill from "E"

was my gas tank switched?

Reply #11 – November 04, 2005, 05:58:56 AM

Quote

Then I must have the most rarest digital gauges of all. I've run my tank down pretty low, like a gallon maybe 2 left, and the gauge ended up being almost dead on. Granted my gauge show's E when I hit 2 gallons or less, but it's still pretty accurate IMO.

i've taken my full digital guage down to 1 gallon and the tripminder read 7 milres till empty. It was really cold that day (about 5 deg. F.) and I stuffed 24 gallons in the car.

was my gas tank switched?

Reply #12 – November 04, 2005, 02:14:21 PM

Well after running out at 2 gallons, the car took in 22 gallons at the gas pump. I think the general consensus here is that the owners manuals were wrong. Some cars have the 15 gallon tank and some have the 22 gallon tank.

was my gas tank switched?

Reply #13 – November 04, 2005, 03:28:17 PM

The whole gas tank debate has been going on for a few months, both here and on the NATO board. One guy over there said he was bored one day, had his old tank out on his 1987-88 TC (which is a 22.1 gallon according to manuals), and decided to fill it with water. He filled it 1/2 gallon at a time with a measuring device (milk jug?). He said he filled it 50 times...which would make the tank 25 gallons. I believe him. But I don't believe the tank is rated for 25 gallons either.

There were three different sized tanks for our cars between 1983 and 1988. Papa Bear is rated at 22.1 gallons; Mama Bear is 20.6; Baby Bear is 18.1. Those are the official ratings. Physically there are differences between all three, and I can spot them in a heartbeat. It's hard to describe with words though. The 18.1 gallon tank was only for 1983-86 turbo cars. The 20.6 gallon tank was used in 1983-4 and possibly early 1985. From 1985-88, all V6 and V8 cars had the Papa Bear. And 1987-88 Turbo Coupes had Papa Bear. These are facts, no BS.

But back to capacity. Can you overfill the tank, past the rated capacity? Possibly. There are some internal sumps that could theoretically hold a bit more. Also, you can squeeze at least one more gallon into the filler neck; general consensus is closer to 2 gallons. So on a dead empty (read: new) 22.1 gallon tank installed on your car, you can get 25 gallons in if you count those sumps and the filler neck.

But in the real world, with a tank you've already been using, I don't think there can be a realistic way to put 25 gallons in. You'd have to have totally sucked the tank dry, or have a pinhole leak somewhere. And these pumps are designed to stop working with about 2 gallons left in the bottom. In other words, if you ran the car way past E and ran out of gas, stalled on the side of the road, you still have two gallons in the bottom of the tank that the fuel pump pickup cannot physically reach. If you then get towed to a gas station, and then proceed to put 25 gallons in...the gas station has cheated the pump. It's just not possible. There are physical limitations to a container, and a gas tank cannot hold more than it can contain.

What is uncertain is the nature of the relationship between the sending unit and the gauge. There were different sending units for buttstuffog and digital, and also different ohm ratings for empty and full. This can get very confusing. And the information that you glean from the gauge can also be skewed. Lots of factors, no definitive answers. As I said...take a guess.

was my gas tank switched?

Reply #14 – November 04, 2005, 04:09:30 PM

Quote from: EricCoolCats

The 20.6 gallon tank was used in 1983-4 and possibly early 1985. From 1985-88, all V6 and V8 cars had the Papa Bear. And 1987-88 Turbo Coupes had Papa Bear. These are facts, no BS.

Woud the "possible" early '85 20.6 gallons correspond to the '85 that got the narrow rear end?

Like I mentioned earlier, I've run my car 1/4 past E (early '85 Cougar), and only put in ~17 gallons. Either the sender is screwed up or I have a different tank in my car. Do all tanks use the same sender? (assuming an anlogue dash)