Fuel delivery woes

[matrixx]

OK I didn't want to start a new thread for a simple question but the search function didn't bring back exactly what I'm asking.

Anyway so I have been using an external fuel source to get my car running and moving. The PO installed a new gas tank but failed to coat it so it has surface rust and a spot that looks suspicious. PO claimed to have cleaned the lines and so forth but that was 5 years ago. I want to connect my engine to the tank so I can have more than a half gallon fuel container haha. What would y'all do in this situation? I don't want to gum up my new Carb. I have 2 filters in line from pump to Carb right now. I'm thinking to blow out the line with compressed air and put another filter right where the line comes through the engine bay. Then add about 5 gallons and hope for the best. I just figured I'd ask before I bring more trouble upon myself.


Here are some pics of said suspicious tank.

 

[caspianwendell]

If the car has been sitting awhile I would pull the tank, clean it and the lines before hooking it to my engine...just my opinion

 

[matrixx]

So pull the tank, pop out sending unit, and what would you use to clean it? Fresh gas? Any product you recommend?


Fuel guage reads 1/8th tank but it may be wrong.

 

[caspianwendell]

So pull the tank, pop out sending unit, and what would you use to clean it? Fresh gas? Any product you recommend?


Fuel guage reads 1/8th tank but it may be wrong.

fresh gas wont be strong enough. they make specific products for this, not sure whats availible in your area but check with your local favorite auto parts store. The main thing I would worry about is debree in the tank but you can let the tank dry and check it with a mirror...tanks are cheap so I would not put a lot into an old one

 

[matrixx]

So pull the tank, pop out sending unit, and what would you use to clean it? Fresh gas? Any product you recommend?


Fuel guage reads 1/8th tank but it may be wrong.

fresh gas wont be strong enough. they make specific products for this, not sure whats availible in your area but check with your local favorite auto parts store. The main thing I would worry about is debree in the tank but you can let the tank dry and check it with a mirror...tanks are cheap so I would not put a lot into an old one

Yeah I agree with you there, I was just noting that since it was a brand new tank and the car never really was run with the new tank. PO said he only put about 2 gallons in it and the old Carb kept giving him trouble and then life happened to him so the car just sat after that. Maybe I will pull the sending unit and take a peek inside with a mirror and a light.

 

[caspianwendell]

So pull the tank, pop out sending unit, and what would you use to clean it? Fresh gas? Any product you recommend?


Fuel guage reads 1/8th tank but it may be wrong.

fresh gas wont be strong enough. they make specific products for this, not sure whats availible in your area but check with your local favorite auto parts store. The main thing I would worry about is debree in the tank but you can let the tank dry and check it with a mirror...tanks are cheap so I would not put a lot into an old one

Yeah I agree with you there, I was just noting that since it was a brand new tank and the car never really was run with the new tank. PO said he only put about 2 gallons in it and the old Carb kept giving him trouble and then life happened to him so the car just sat after that. Maybe I will pull the sending unit and take a peek inside with a mirror and a light.

You never know it may be like new inside...just a cleaning and fresh paint and away you go

 

[Jeff73Mach1]

Keep in mind that an empty gas tank is a fire hazard and only nonsparking tools should be used around it. Clean rust with a copper choreboy or a scotchbrite pad, treat it chemically- do not sand it with an electric sander.

Replace the two short sections of rubber hose with fresh hose. You should be able to used compressed air to blow out the metal line, but blow from rear to front.

Do not run two inline fuel filters, it will cause fuel starvation.

 

[matrixx]

Thanks jeff, other than scotchbrite any other chemical I should put on that rust?

 

[Jeff73Mach1]

Phosphoric acid will convert the rust to a black oxide. Wash down afterwards with soapy water then plain water before prepping for paint.

If the inside isn't pretty clean, I would replace the tank and save the time and effort.

and please don't blow yourself up!

 

[matrixx]

Not going to use any power tools. I'm going to take a peek inside and see how rough it is or isn't. Then make my decision from there. Can't believe he didn't coat the tank while he replaced it.

 

[72HCODE]

as cheap as a new tank is, i would just replace it why chance it.

all those tank coating liquids have been reported to fall apart over time and release pieces into the fuel that clogs the filter.

the new tanks are also galvanized to help prevent surface rust from forming.

 

[caspianwendell]

you can also use white vinegar to aid in rust removal

 

[turtle5353]

My dad went through the same problems as you with his 66 mustang. Put a new tank in the car and new carb, but kept having trouble with the carb and filter plugging up. he checked the line from the tank to the pump and it looked good. I pulled the line down out and when we cut it open the inside was rusty as hell. the outside actually looked better than the inside. So we replaced the line from tank to the pump and it helped for a while then the trouble started again. Carb overflowing and shutting down. When he put the carb on he didnt replace the short line from pump to carb. Overall with new lines and tank it was around 200 bucks. if he would of changed them all in the first place it would have saved us alot of headaches!! I would reconmend just drooping the tank and putting in a new one and replaced the fuel lines. I bought the prebent lines from laurel mountain mustang and they worked great and were not very expensive. Just my opinion....little money now will save you alot of headache and time in the future and not to mention a piece of mind knowing that everything is new.

 

[72HCODE]

just a thought,

you can convert to stainless steel, fuel lines and vapor return lines. the fuel sender is also now available in stainless.

i would recommend going stainless in the fuel system. Stainless for the fuel system is nothing like the headache stainless steel brake lines are.

i converted to galvanized tank, stainless main fuel line, stainless vapor return, and stainless fuel sender. with luck i shouldn't have a rusting issue up to the carburetor.

 

[matrixx]

Good idea. Where is this vapor return line supposed to be? My car was missing some things under the hood I don't recall seeing a return. A pic would be great.

 

[Jeff73Mach1]

vapor return line runs in the transmission tunnel and comes up near the center of the firewall.

 

[matrixx]

vapor return line runs in the transmission tunnel and comes up near the center of the firewall.

Where does that end connect at?

 

[Jeff73Mach1]

to the carbon canister if you still have one.

 

[72HCODE]

the vapor line comes of the top of the fuel tank, rubber hose then the line runs tight to the body through the trans tunnel up the fire wall and then another section of hose connects to the vapor canister on the passenger side of the engine bay. the charcoal or vapor canister is a pancake blue looking thing with a small blue mushroom on top.

the 70+ mustangs had to switched to a sealed fuel cap for government emissions but the tank needs to breathe to prevent a vacuum from forming inside the tank as fuel is used and collapsing the tank. so the vent from the gas tank was funneled to the front of the car through the vapor canister which connects into the air cleaner before the intake so it uses the natural vacuum of the motor to change the air inside the fuel tank. the original air cleaner has a fitting and a secondary filter that connects to the vapor can.

this sucked the fuel vapor from the gas tank into the motor and allowed the pressure inside the fuel tank to equalize with the outside air to conform to government fuel vapor regulations.

many people when they change intakes and carbs ditch the carbon vapor canister or disconnect it. then wonder why they have a gassy smell under the hood all the time.

the canister has a second function as well, since the fuel tank is constantly vented by the vaccum of the engine, you do not get water condensation inside the fuel tank which helps prevent the tank from rusting on the inside walls and clogging the fuel system with rust particles.

this is the canister.

on the original ford carburetor the fuel vent was located on the side and was outside the air cleaner body so ford needed to run a line from that vent down to the vapor can as well, on replacement carbs like the holley the fuel vents end up inside the air cleaner body so they are vented by the intake air and don't need to go through the vapor can first.

the air cleaner to vapor can hose is that special foil wrapped paper hose that is about 1.5" diameter and about 4 feet long. most cars don't have this tube anymore because it fell apart. you can still find replacements for it from 1980s cars.