• Hello there guest and Welcome to The #1 Classic Mustang forum!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

Fuel filler Mods

I think I finally found an advantage to living in California. I have never had any splash back problems with our environmentally friendly, stupid proof fuel nozzles. I guess I better never travel out of state!
 
I have to admit I am a little disappointed now that I can see how this "kit" solution works. It is more like a solution for guys who don't have access to or the ability to "do it right" by modifing the tube by cutting it and welding in the aftermarket piece. I'm sure it can work and might last but denting the tube out of round to wedge the piece and then securing it with JB Weld seems a little McGyverish to me.

I'm not sure what equipment was used to "resize" the insert flange but it doesn't look too sophisticated judging by the results. If someone wanted to go this route they can simply grind off the outer lip to size or roll it back as seen below with simple hand tools. Not rocket science. Myself, I'd advise cutting and welding so you can do it right once and forget about it.
View attachment 31208

it was definitely meant as a solution for those with no equipment or skills to weld, and judging from the responses it worked well. As I recall from our conversations the JB Weld was added as a CYA. He reasoned that if the car was sold and someone jammed a fuel nozzle down and missed the smaller hole in the insert they might dislodge it and he was concerned about possible litigation. There are more lawyers in California than many entire nations.
 
Last edited:
Mach1Driver: Thank you for the info and pdfs. I did sign up for the forum hoping that was the picture problem but that didn't solve it. I ordered the materials, including a filler neck for my Cougar and will go through my options when I have the parts in hand. Thank you.

Horseplay: I don't think a "McGyverish" process is bad in some cases if it works. In this instance its not a part that will be seen so a few dimples is no big deal. However I agree on the JB Weld issue. I'm not a fan of the potential for failure and having the insert get pushed loose and end up in the tank.

I'll keep you guys posted on my process as it evolves. Right now I'm waiting on parts delivery. Hopefully Monday.

Once again I appreciate the responses and the welcoming of a Cougar owner into a Mustang forum!!
 
To me "McGyverish" stuff really refers to something that can work in a pinch but not meant to be long term. Something out of sight is also out of mind. When it comes to that kind of thing I typically try to over do it so I am not surprised later after I have forgotten all about it.

A much better, yet still fairly easy, approach to this might be to do the dimple thing, and drop the part in but have drilled a couple small holes on opposing sides in line with the insert edge so one could put in a nice tack weld to hold it. Even a bad welder could do that as you can clean it up with a grinder as the welds would be on the outside. For me I would feel better doing this than JB Weld.
 
A much better, yet still fairly easy, approach to this might be to do the dimple thing, and drop the part in but have drilled a couple small holes on opposing sides in line with the insert edge so one could put in a nice tack weld to hold it. Even a bad welder could do that as you can clean it up with a grinder as the welds would be on the outside. For me I would feel better doing this than JB Weld.

That's a good approach, but you still have to have the equipment or access to someone that does.
By the way, how is your TIG welding coming along?
 
By the way, how is your TIG welding coming along?
Haven't done a thing yet. :( What free time I can manage, that would usually be spent in the garage, is spent in the car. Unfortunately, the season is going by fast so pretty soon I will be back to melting some metal. It's projects like the fuel filler mod where a TIG can be a really great tool in the arsenal.
 
Ok ... I joined this forum a while ago, have visited a few times since, but don't know if I ever posted anything.

I also never saw all this activity in this thread referencing the thread over at 1969stang.com or myself until TODAY (yes, I'm late to the party).

Terry (Mach1 Driver) provided a link to this thread and as he said his work and other's work posted in THIS thread was the inspiration for my "NO-CUTTING or WELDING" solution for this filler neck insert.

SO YES … I'M THE FILLER NECK INSERT GUY.

For those wondering, I'm crimping the OD of the insert down in a Gates Hose Crimping Machine.
I'm crimping it down just enough so it can slip past the bend, but not be too sloppy once up in place.
There are also three different tubing ID's used on '65-70 necks (stock '65-66 Necks, '65-68 Conversion Necks, & '67-70 Stock & Repro) so I've had to come up with 3 different crimp specs.

For my install, the insert is mechanically held in place with 3 punch indents above the insert's crimped down flange and 7 below it.
If the indents are deep enough, you "could probably" do without the JB Weld. However the JB Weld is an insurance policy that the insert will stay in place.
I install the insert cocked with more of the gap at the top; the JB Weld then goes between the tube wall and insert top & sides (only) leaving the bottom open for fuel drain back. Once fully cured, the JB weld becomes a solid wedge shaped horseshoe.
The filler neck tubing I.D. is somewhat rough, so that also helps the JB weld adhere and stay in place.

Life has been pretty busy since I started doing this March 2018 so other than the thread over at 1969Stang.com, I've not been "actively trying to sell" these things. It certainly did not help sales when the thread over there lost all the pictures either ... and after that happened I did plan to post in a few forum "For Sale" sections, just never got around to actually doing it.

Anyway, I've got quite a few inserts kits and some completed necks ready to ship if anyone is interested. I can also turn around complete necks within a week or so if I don't have what you need in stock.

Attached are all the current docs with lots of pictures and info ... updated to the current files 08/20/2020.

Thanks,

Doug
 

Attachments

  • Fuel Filler Neck & Insert Kit Price list.pdf
    1 MB · Views: 11
  • Fuel Filler Insert Instructions-R7.pdf
    1.3 MB · Views: 5
  • Fuel Filler Insert Tool List-R6.pdf
    696.9 KB · Views: 6
Last edited:
Ok ... I joined this forum a while ago, have visited a few times since, but don't know if I ever posted anything.

I also never saw all this activity in this thread referencing the thread over at 1969stang.com or myself until TODAY (yes, I'm late to the party).

Terry (Mach1 Driver) provided a link to this thread and as he said his work and other's work posted in THIS thread was the inspiration for my "NO-CUTTING or WELDING" solution for this filler neck insert.

SO YES … I'M THE FILLER NECK INSERT GUY.

Thanks,

Doug

Hey Doug,

Is this still the best available solution to the problem? Are you still selling these? How much? Thanks!
 
Is this still the best available solution to the problem?
I think Doug would agree that it is not the only solution, and the best solution would be the one that best matches your skill level or desire. Doug's approach certainly has it's merits and I applaud him for it. I had already made a modification that works quite well, but I bought one of Doug's kits, because until I learn to TIG I feel its the best way to go.
 
I'd like to add that one of the real issues with our cars is the close proximity of the fuel inlet to the actual tank body. As the tank fills up this starts to create issues. I have made a few filler necks with a fully welded in piece with a smaller port with flapper and small vent holes and they work fairly well but not always perfect. Some pumps discharge at higher volumes/force than others which can cause the nozzles to self-shutoff frequently. The trick is to avoid sticking the nozzle in any deeper than necessary and I have also found that if I angle the stream to deflect off the side of the tube rather than as straight shot into the tank it does much better as well.

A future planned modification I have in mind is to weld in a couple bungs in the tube before and further down beneath the block-off plate into which I would screw in hose nipples (after the filler tube passes through the rear panel) to be used with a hose looped back into the neck above the plate to provide additional venting ability. You see such in lots of newer car fuel neck designs. The idea is to allow the volume of air able to escape to match or surpass the volume of incoming gas. This would help keep the pressures from tripping the nozzle off during fill-ups.
 
I've also come up with a fitting set for adding a 1/8"NPT to 5/16" Hose Barb above the insert for venting the gas tank (as Horseplay mentions in post 291).

For me, I connected it to the 1969 GT500 Recall External Vent Line that I bought from CJPP so my gas tank no longer vents out the gas cap or via a vent dent in the face of the neck.

But it could also be connected to a fitting in the top front of the gas tank to better allow the air to escape while filling up the tank.

See attached

Doug
 

Attachments

  • Modding Neck for Hose Stem.pdf
    261.8 KB · Views: 16
I strongly feel the best place for the additional vent port will be in the tube under the inset plate, closer to the tank. This is where the pressure builds up that causes the pump nozzle to trip. I run an EFI set-up in my car and have a separate vent port on the top of the tank which doesn't eliminate the issue 100%. I think the flow of gas with some pumps is so large it over-paces what the stock filler neck can accommodate at least to the point forces are generated that create the pressure to shut the pump nozzle off. I also think that the earl cars length of filler tube may just be too short to ever function without the occasional trip.
I have learned to just set the handle at a less than max flow position, rotate the nozzle so it rests at about 2 o'clock (if looking down the length of it from the top with it held perfectly upright is 12 o'clock) and inserting it just enough so that it can rest and remain in the tank on it's own. This results in the flow hitting against the left upper side of the tube creating kind of a swirl effect as the gas rushes down into the tank. My thought is that this allows the fuel volume to pass without fully filling up the space leaving room for the air in the tank to escape. 90% of the time I can fill her up without a hick-up this way.

Who would have ever expected it took this much thought and engineering to fill up with gas!
 
Back
Top