Correct position for rubber fuel neck collar on 356C

[Robert Stonerock]

T6 1965C Gas tank. I have tried to find a photo of the correct orientation of the rubber collar and metal "U-shaped" drain insert as it relates to the back of the fuel filler area where the fuel neck enters the filler area on the outer fender. The manual photo suggests it goes inside of the cutout, but searching the web for forum articles, I found 4 different photos that were very different from each other in how they oriented the collar. Some were upside down in relation to each other the rubber collar was completely on the outside on one, which looked correct, but the other 3 had it inside of the opening to the fuel lid area, and the drain tube was not oriented the same in any of the installations as it related to the edge of the rubber collar. I didn't have a photo of it when I disassembled the car and no diagram. I know............big mistake. As a side note, mine had never been apart and I noted that the screws to the inner seal were not as the factory manual stipulated, which was the uppers from one direction and the lowers from the opposite side. Mine had the rears placed from the wheel side and the fronts were from the gas tank side. I have spent a lot of hours looking on the web for photos and have 5 different versions.
Can anyone post a photo of how the outer rubberneck flange of the collar is really supposed to fit against the body?
Thanks, Bob

[Doug McDonnell]

Here is what I have on my 64 C Coupe My car is in the garage but I can get any other angle you would like. I installed mine the way it was when I purchased the car 8 years ago. However I do not know if it was original. I think it was based on overspray from previous paint job on collar and U shaped drain piece.

[Robert Stonerock]

On the photos, I noticed the metal drain portion is too far inside the rubber flange and it appears "puckered where the holding clamp is located, suggesting that the rubber seal is 180degrees inverted? As a side note, the head of the tapping screws to the metal inner seal portion appear to be round and doesn't have a washer underneath it, which is not per the parts manual for T6 cars??? The original screws were hexagonal heads 4.8X19mm. (Available from Stoddard as a kit, or from Porsche with the part number from the manual). The clamps in both applications are not per factory either, so I can only assume that while it works, it is not the way it was originally assembled at the factory?? I saved the original rubber inner tank neck seal and it is contoured much differently than the current reproductions, but I evidently discarded the outer seal when I secured the reproduction parts, so I do not know if it is molded differently than the originals??? I do appreciate the posting, as it helps me narrow the orientation options.
Bob

[Brad Ripley]

In the photos --
Screws are wrong. should be DIN 7976 4,8 x 19 which look like below.

The nuts for the screws are painted (looks POR 15 over rust). should be clear zinc.

Clamp is wrong. should be the usual Norma but I have seen original cars with the German hat clamp (as used on breather hoses on 4-cam engines).

Drain tube should not have a clamp

Rubber collar looks wrong or it's oriented incorrectly as Robert suggests. The collar has provision for the drain trough but doesn't show in the photo.

This tank filler pipe set up is illustrated in the Workshop Manual, page SF22 of the Supplement. There are two versions of this page: (1) the printing of Nov '61 shows no drain trough and (probably) the Norma clamp. The screws go from the tank side of the flange plates. (2) the Jan '63 printing shows a drain trough and the hat clamp. The two bottom screws go from the outside; the two upper screws go from the tank side (easier to install the screws!). And, the screws shown are DIN 85, not the DIN 7976 spec'd in the parts catalog!

Oh, BTW, page 21 lists chassis numbers for the T-6 fuel system for Coupe, Cabrio, Hardtop and Roadster all ending in "601" -- what a coincidence, or a mistake. But take a look in the T-6 Parts Catalog and will see conflicting chassis numbers. So, I dunnknow ....

[Robert Stonerock]

Brad, or............. " I could not find the long drain hose and clamp in any of the manuals that I reviewed. Fortunately mine were ok, but If I read your note correctly, it does not have a clamp at the top per factory????? The workshop manual I have shows the rubber collar with the metal drain piece, more of a drawing than a photo, but it is difficult to tell if the wide portion goes inside the opening to the fuel flap area, or it rests against the metal on the outside, which makes the most sense when I look at where the metal drain portion is in relationship to the rubber collar edge. Do you know if this is the correct orietation, ie. with the rubber collar resting against the wheel well of the fuel opeining for the collar of the gas tank?

Thanks, Bob

[Brad Ripley]

yes, the metal drain piece (644-201-179-00) is right in front of your eyes when you look up into the wheel well which puts in the lowest part of the gas filler cup in the fender.

[Wil Mittelbach]

Bob -
Perhaps responsive to your subj query:-
Herewith are photos showing the new collar on the fuel tank neck with its original hardware, screws, clamp and drain tailpiece in their original positions upon the re-installation of the original fuel tank in my unrestored 65C cab.
Being in the fenderwell, the original tailpiece and clamp were a bit corroded, which I cleaned and painted black rather than re-plating. The original collar was also in reasonable condition, but somewhat age hardened and therefore replaced.
- Wil

[Robert Stonerock]

Thank you!! The photos confirmed my suspicion of how it should go together.I will finish buttoning it up this afternoon.
Bob
Back again.....I couldn't get the collar to conform to the outside of the filler opening, as per the photo supplied by Wil. It was so stiff and narrow that it kept wanting to ride inside the opening for the filler tank at the top portion. I tried rolling the edges back to the outside of the opening, but the rubber was just stiff enough that it would "pop" back out as I adjusted the clamp. I am assuming that it's edges are supposed to roll over onto the outer edges of the opening and for a seal that way?? I reviewed the supplement page again with the 61 and 63 update as mentioned by Brad, but the drawing is just too vague as to tell whether the collar tucked inside the opening or stayed completely on the outer surface. Only one post that I could find showed the rubber collar inside the opening around the filler neck itself. It looked right, but conflicts with the only two photos I could find posted on the forum, which states that per their original seal, it was completely on the wheel well side of the opening. Anyone got an original photo or knowledge. I still think Wil is right, but I am really struggling trying to get the collar adapted per his photo.

Bob

[Wil Mittelbach]

Bob -
Possibly the problem may be that your replacement collar is stiffer and/or thicker than others. Warming it a bit may make it more supple.
Zooming-in on my photos, one can see the collar's upper lip flared out over the filler opening per the factory installation of the original collar.
- Wil

[Robert Stonerock]

Wil,
I found my records stating that the rubber collar was purchased in 1989, so it was a little stiff. It was probably more pliable when new?? I heated it and then rolled the edges and taped them while the rubber cooled, before installing it one last time!!! I had to partially remove the tank for about the 5th time to get the collar back around the tank neck. It worked, and I was able to get it sealed and flattened around the inner side of the wheel well. From the fuel cap side, rubber does not go inside the housing, as seen in many posts. I enclosed several photos and one of the original inner seal, which is quite different than the reproduction. it works, but I will seal it with Wurth Seam seal around the edges, before clear coating the assembly. On to converting to H4 lights and relays.

Bob

[Wil Mittelbach]

Bob -
Well done - - despite the hassles of multiple tank and stiff collar manipulations.
The photos with the tank neck's trunk thru-wall surround and collar installations look as original, complete with a proper period roll-up clamp.
It looks great and as new.
- Wil
In Huntington Bch.

[Robert Stonerock]

I will post two final photos of the drain hose positioned which shows where the original clamps went. The hose is the original one, which I removed earlier. My clamp in the photos is loosely positioned just below where one can see the original hose clamp was.
The last photo shows the fuel tank vent hose and drain hose positions. Brackets around vent hose are not fully closed as this was final fit before buttoning up everything. The rubber pieces around vent hose were copied from the originals, which had cracked and were split. I painted the welded hose brackets black after closing them.

Hope this helps someone else along the line.

Bob S.

[Jack Banville]

Hello,
I'm assembling a 63 T6 that I didn't disassemble. Nothing was marked... These photos and descriptions are helpful but I still have questions. The manual isn't quite clear, at least to me.
What is the sequence of assembly for the tank, metal plate that fits on the outside of trunk, rubber gasket, and the collar?
It appears that the top two screws are inserted inside the trunk and thread into the captive nuts on the metal plate on the outside wall of the trunk. The bottom screws are inserted through the metal plate on the outside of the trunk wall. What do the screws attach to inside the trunk?
The hardware specifics are mentioned above. I did not see them on the Stoddard site. I realize this is an older thread.
Thanks in advance,
Jack

[Doug McDonnell]

From the guy who did it all wrong earlier in this thread (me) Robert did it correctly. Each of the metal plates has 2 U nuts (clip nuts). So all 4 screws go into clip nuts. Make sure you orient your plates correctly so screws go in from correct sides. Also make sure that the plates are oriented so holes in the plate for fuel overflow tube is in correct position. Install plate on filler neck then filler neck through sidewall then after filler neck has cleared sidewall rubber gasket then 2nd metal plate and finally filler neck rubber collar with it's Norma clamp. After you have everything in correct order you will get the result Robert did. Final step is to install fuel overflow tube which connects to fuel tank by a small piece of fuel line without clamps. If you want shiney new clip nuts Stoddard has a scew,washer,clip nut package: http://www.stoddard.com/64420100206-nla.html

[Jack Banville]

Ahhh, there are 2 metal plates! That makes sense.
Doug, thank you very much! And thanks for the Stoddard link.
Jack