Fuel Tank swap 70 Mach 1

[Print Dad]

Hello,
I need to change the 22 gallon gas tank on my Mach 1. The car has been in the garage for 22 years and I am having lots of fuel problems. I think the best bet is to swap the tank.
The tank has no straps...looks like bolts around the edges. I have never changed a tank but have some mechanical skills. I can change lifters, carbs, clutch etc.

Can someone tell me the proceedure for tank removal. Does it come out the top (Trunk) or from the bottom. If possible does anyone have a link to instructions. Also any tips when doing. I know I will change the sending unit and sock?. I could use some help as I have been having lots of fuel problems causing me to replace the fuel pump, carb twice,etc.Thanks in advance.......Jim

 

[Grabber70Mach]

This might help you out.


Fuel Tank Installation - Mustang & Fords Magazine

 

[Print Dad]

Hello Grabber70Mach,
Thanks thanks thanks.. This is just the type of info I was hoping to get.
What a great link. I have bookmarked it and have already read through it.
It gives me a much better idea of what I need to do. Seems like with the
proper replacement parts, this should be a snap.
The one thing I don't understand is the top of the tank the bottom of the trunk.
I need to get out to the garage and check the trunk. Of course my wife wants to paint 2 rooms so I need to juggle my time after work.

Being new to the forums I don't know how to check your profile but I assume you had/have a 70 Mach. They are great cars and I have owned this for about 34 years. The car was in real good shape when I took it off the road 21 years ago when my son was born. It was our plan to give it to him but it is not practical as an everyday driver around this area. Pretty high theft. The bad feature is that the previous owner painted the car Black. It was grabber green by signs in door jambs.

I would like to get this car going again. I still drive Mustangs as my daily driver and plan to continue doing so. It is my wish to purchase a shelby when I retire.

Once again your post was simple but so valuable to me ......Thanks.......Jim

 

[bnickel]

the top of the tank is the trunk floor. not exactly comforting is it?

there is a kit you can buy called "Tanks Armor" that puts a very thick gauge piece of metal over the tank designed to offer some protection against fuel entering the passenger compartment, this would be especially nice if you have a fold down seat in your mach. here's a link

Tank_armor

FYI, if your fuel gauge currently reads right, re-use your current fuel sender, just replace the fuel sock on the end of it. a lot of people complain that their fuel gauge doesn't work properly after replacing the fuel sender or replacing the tank. this is because some of the aftermarket sending units are junk, not all of them but it can be kind of hit or miss whether you get a good one or not. i got lucky when i replaced the tank in my 69 as the fuel sender that came with it works perfectly but not everyone is so lucky.

 

[Grabber70Mach]

Hello Jim

Yes I have a 70 Mach 1 that I am currently working on, I've had it for about 11yrs.
But with 2 kids it kinda takes longer to do some things than I would like it to. Bicknel has already answered your question about the tank being the floor. I haven't done the tank armor like he recommended, but have looked at it and thought about it as a future project. When you get the chance post some pics of your car as we all like to see the ponies. Ted

 

[Print Dad]

Hello bnickel,
First thanks for the reply. It is a bit scary to think the tank is the floor
of the trunk.
Thanks also for the great links.I have bookmarked them both and have already checked them out.

I notice you are on of the founding members. That is really nice. I use forums to help
me on my Macinstosh computer and car info. Forums when used properly can be such a great help. I hope to be able to contribute in the future.

Again I thank you and all the others who took the time to read and/or respond.....Jim

 

[bnickel]

actually the "founding member" title can be a little misleading, this forum was here for at least a few years before i found it.

 

[Print Dad]

Hello Grabber70Mach,
Sorry for delay in posting. I go the tank and it was a snap to put in. The links and pixs were a great help. One other small question, when I removed the trunk rug, there was a form of insulation? over the tank. It is about 3/4" think and is like a stiff tar paper. Any idea what this is and where it can be bought? Oh yeah, my wife is buying me a compressor for Christmas. I know this will help out.

I thank you for the help and for all the members....Happy Holidays.......Jim

 

[Tim65GT]

It's called underlayment

View attachment 286081

 

[Grabber70Mach]

Glad to hear you got it all taken care of, the link above will lead you to what you are looking for. Hope you all have a Happy Holidays.

 

[Print Dad]

Hello Tim65GT and Grabber70Mach,
Thanks for link. Yes this is what I was talking about. I wish I had seen it as this is where I got the tank. No big deal as I am sure I will need more stuff as I go along.

Thanks again and Happy Holidays.........Jim
Oh yeah I have a few old pixs of the Mach that I may try to post. The car looks the same but is a whole lot dustier. Take Care

 

[66 Restomod]

...FYI, if your fuel gauge currently reads right, re-use your current fuel sender, just replace the fuel sock on the end of it. a lot of people complain that their fuel gauge doesn't work properly after replacing the fuel sender or replacing the tank. this is because some of the aftermarket sending units are junk, not all of them but it can be kind of hit or miss whether you get a good one or not. i got lucky when i replaced the tank in my 69 as the fuel sender that came with it works perfectly but not everyone is so lucky.

I recently found that the brass floats, and the socks for that matter, were defective on two import senders I bought. You can buy a new brass float in a Ford package from NPD for about $6, which I recommend if you are replacing the sender with an import. I haven't had the sender itself go bad, but have heard of that problem too.

Here are a few photos and a brief writeup of what I found if it helps anyone else:

Restoration and Modification of a 1966 Mustang "Restomod": Brand New Repro Parts, Part II: More Adventures in Head-Scratching

 

[bnickel]

i believe Scott Drake also has new stainless steel sending units which seem to be of much better quality than the rest of the repro sending units, plus they will work with E-85 fuel if one should ever decide to switch over to it. they also have new stainless steel complete fuel tanks as well, match that with the stainless sending unit, stainless fuel lines and an E-85 compatible carb and you'd be all set for the switch.

as a side note one could also have their original carb re-done to be compatible with E-85 as well, if you could find a rebuild kit designed for E-85 and have the carb body zinc or ceramic plated, IIRC