How to replace the gas tank, the easy way with pics!

Connie

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Even early unleaded was red. I don't remember when it changed to yellow, sometime in the mid to late 80's I believe. I know here in Michigan, 10% ethanol was started in 1980 in various places around the state. By the 90's it was everywhere though.
But yes, I do remember leaded gas.:)

I haven't seen no-ethanol since I was in South Carolina a few years back. Other than Mexico, where it's still available too. You probably CAN get it somewhere here, but everything I have runs fine on the up to 10% crap we have here now. At least we still have Ultra 94!
 

SupraGuy

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A few things about gas.

The colour is a dye that is put in. The colour is a regulated one. The dye for gasoline which has been taxed for road use is supposed to be orange (Though it does appear yellow.) Gas which is intended for farm use is purple. The only difference is how the gasoline was taxed. Aviation fuel is clear. Since the 70s at least, I only remember gas being the colour that it is, but since the colour is artificial, and nothing to do with the refining process, it could be different in different areas of the world. I can remember some of my friends who were farm kids changing their fuel filter to hide the fact that they'd been driving around with purple (farm fuel) gas.

Gasoline without ethanol in it does give better fuel economy because the amount of potential energy per unit of volume is greater, therefore less of it needed to be burned to produce the same amount of work. (Work from a physics standpoint, that is.)

Higher octane gasoline burns slower. Ethanol enhanced fuels have a higher octane rating, which allows them to burn with less pre-ignition since they are more able to take compression and still need the spark plug to start ignition. Leaded fuel also burns slower because of the mass of the lead. Old unleaded gas had to be refined for heavier hydrocarbon content which is more expensive, so ethanol is used in order to provide a similar effect. E85 gets relatively crappy fuel economy, but since it can be used with really high compression (Or really high manifold boost pressure) it can make a lot of power.

I kind of dislike the term "octane rating" because it really has little to do with the actual chemical content of the fuel. It's a rating of how much timing advance a specifically designed motor can run at a certain RPM before detonation occurs. (Actually 2 different ratings, averaged)
 

Connie

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A few things about gas.

The colour is a dye that is put in. The colour is a regulated one. The dye for gasoline which has been taxed for road use is supposed to be orange (Though it does appear yellow.) Gas which is intended for farm use is purple. The only difference is how the gasoline was taxed. Aviation fuel is clear. Since the 70s at least, I only remember gas being the colour that it is, but since the colour is artificial, and nothing to do with the refining process, it could be different in different areas of the world. I can remember some of my friends who were farm kids changing their fuel filter to hide the fact that they'd been driving around with purple (farm fuel) gas.

Gasoline without ethanol in it does give better fuel economy because the amount of potential energy per unit of volume is greater, therefore less of it needed to be burned to produce the same amount of work. (Work from a physics standpoint, that is.)

Higher octane gasoline burns slower. Ethanol enhanced fuels have a higher octane rating, which allows them to burn with less pre-ignition since they are more able to take compression and still need the spark plug to start ignition. Leaded fuel also burns slower because of the mass of the lead. Old unleaded gas had to be refined for heavier hydrocarbon content which is more expensive, so ethanol is used in order to provide a similar effect. E85 gets relatively crappy fuel economy, but since it can be used with really high compression (Or really high manifold boost pressure) it can make a lot of power.

I kind of dislike the term "octane rating" because it really has little to do with the actual chemical content of the fuel. It's a rating of how much timing advance a specifically designed motor can run at a certain RPM before detonation occurs. (Actually 2 different ratings, averaged)

Some good information there. Never knew how they measured the octane ratings, and didn't expect the method you describe; seems really obscure.
To be honest, gas here looks clear to me, not yellow, but they do the same dying thing here with diesel; farm use has red dye and isn't taxed.

The only time I run 91 or higher is in my boosted cars; the Merkur is running 15psi, but is a fairly low compression engine, so I can get away with 91 without the knock sensor retarding the timing at WOT under boost. The Accords always get 87, because that's what they were designed to run on.

The RX7 can't handle much over stock boost of between 7 and 8 psi with 91, but with 94 I can run 9-10 without any pre-detonation.

A lot of people share the misconception about the higher octane rating meaning more explosive, when in reality its the complete opposite of that.

I've always thought of a higher octane to mean a more controlled burn. (less volatile at higher temperatures and pressures.)
 
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Rusty Accord

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Some good information there. Never knew how they measured the octane ratings, and didn't expect the method you describe; seems really obscure.

A lot of people share the misconception about the higher octane rating meaning more explosive, when in reality its the complete opposite of that.

I've always thought of a higher octane to mean a more controlled burn. (less volatile at higher temperatures and pressures.)

Yup, about the only time I run 91 octane, is on a road trio with my air cooled VW, as I want a slower burn of the fuel to help cool the heads.
 

puzzlemaster94

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Nice job on the DIY, great info.

Now I have to ask, why have 4 6th Gens. I'm not blaming you, because I'll likely get my 3rd one day, but just curious.
 

Connie

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Nice job on the DIY, great info.

Now I have to ask, why have 4 6th Gens. I'm not blaming you, because I'll likely get my 3rd one day, but just curious.

Well two of them are just parts cars; I was hoping to find a good gas tank in one of them, but turned out both parts car tanks were rusted out in the same spots. So I had to buy 2 new tanks for Connie and Midnight. Connie ($700 4 years ago) is my daily/winter car and gets over 200km a day, and Midnight ($800, but in really nice shape now that the leaks are fixed) is going to be my girlfriend's daily/winter car, because she doesn't drive much and my commute is a car destroyer. She is also neater than I am, and will keep it nice enough to hold some value if we decide to sell it.

I might fix up the green sedan just to sell it, as I got it for $400 and it just needs a gas tank, brakes and a hood latch. I could probably make a few hundred bucks on it.

The silver coupe parts car ($200) was driven directly into a tree at I'm guessing 50-60 kph, so it'll stay a parts car.

For dailies that need to function, the Accords are perfect and the price was right. And that V6 power sure is nice, too.

I actually just found a black 01 F23 sedan with a blown head gasket for $300....the clear coat on it is still perfect and it's clean, rust free and low mileage. Something like that certified and e-tested would get between 2-3 thousand here, so I might pick up that one too, drop in an engine, and try my luck making some money off of that one too.

There are a lot of these cars around; I've made my money back on the parts cars already by posting part-out ads in the classifieds, and still have almost two whole cars left. I like supplementing my income by flipping cars from time to time; before I travelled so much for work, I used to flip 2-3 cars a year and make a few thousand dollars extra a year.

I bought my house in large part because of the garage and the space to keep extra cars around. 5 years ago it was Hyundai Accents; at one point I had 5 of those laying around, all bought for less than $500.
 
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Rusty Accord

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I will try and walk you through step-by-step as I get this tank replaced in my black 2000 V6 coupe.

All the bolts you need to take out apart from the large sub-frame bolts and brackets are pictured here. The only thing still holding the sub-frame into the car at this point should be the sub-frame to body bolts. Apparently on I4 cars there are only 4, but I only have V6 cars, so I can't confirm that. There are 8 12mm hex size bolts that hold on the brackets and 4 17mm hex size bolts that go through the sub-frame into the body. Remove all of the small bolts and 2 of the 4 large bolts (opposite corners). Leave the remaining 2 large bolts in there and get a jack to support the sub-frame on the cross member underneath the tank. Then remove the last 2 bolts.

I just want to add that I'm currently doing this job (I followed these instructions where they applied) on an I4 model with drum brakes, and found that you need to disassemble the drum brake assemblies, so you can get the cables out of the backing plates.There's 2 small M6 (10mm headed) screws that hold the cable to the backing plate, plus 1 short M8 (12mm headed screw) that holds the cable to the front link arm on each side. Unfortunately with drum brakes you have to disconnect the lines, so keep that in mind. You also have to remove the thru bolts for the bottom of the strut to the knuckle. If you're changing struts, this is a good time to do it. Salt belt owners take note here, the thru bolt can rust to the metal sleeve in the strut, and cause a problem, as it won't come out due to the amount of rust it may have. I only mention this, as I ran into it on the left side of the car (where they sling the salt on the road), and had to cut the thru bolt to get it out/off the car. Then you can remove the 4 bolts that hold the rear subframe to the car and drop the unit out.
What I'm getting at, is that there are only a few bolts on the I4 models versus the V6 cars.
 

Connie

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I just want to add that I'm currently doing this job (I followed these instructions where they applied) on an I4 model with drum brakes, and found that you need to disassemble the drum brake assemblies, so you can get the cables out of the backing plates.There's 2 small M6 (10mm headed) screws that hold the cable to the backing plate, plus 1 short M8 (12mm headed screw) that holds the cable to the front link arm on each side. Unfortunately with drum brakes you have to disconnect the lines, so keep that in mind. You also have to remove the thru bolts for the bottom of the strut to the knuckle. If you're changing struts, this is a good time to do it. Salt belt owners take note here, the thru bolt can rust to the metal sleeve in the strut, and cause a problem, as it won't come out due to the amount of rust it may have. I only mention this, as I ran into it on the left side of the car (where they sling the salt on the road), and had to cut the thru bolt to get it out/off the car. Then you can remove the 4 bolts that hold the rear subframe to the car and drop the unit out.
What I'm getting at, is that there are only a few bolts on the I4 models versus the V6 cars.

Thanks for the update! I was wondering what the differences were going to be for you when you got around to doing this on a 4 cylinder car. Still doesn't sound too bad though. I'm sure you'll have it back together in no time.
 

Rusty Accord

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Thanks for the update! I was wondering what the differences were going to be for you when you got around to doing this on a 4 cylinder car. Still doesn't sound too bad though. I'm sure you'll have it back together in no time.

I've already got most of it back together. What I've got left is reassembling the brakes, and bleeding them, and re-hang the exhaust, and weld my sleeve on where I cut the pipe (no flanges to unbolt). I still have to put fuel into as well, but most of the little crap is already done.
 

Gradfien

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I think Im still a few years from needing to replace my tank but Ive been realy curious if the 7th gen accord tanks would fit. We had a 6th and a 7th gen up at the same time at work, and the subframe/tank shape looked the same. The only noticable difference seemed to be the 7th gen tank is plastic, meaning no rust.
I suppose I should just quit trying to get somebody else to try it for me.

Sent from my SAMSUNG-SGH-I747 using Tapatalk
 
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