What goes beneath fuel tank on T6

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Robert Reed
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What goes beneath fuel tank on T6

#1 Post by Robert Reed »

Hi folks, I'm in the process of getting my '62 back on the road, and need a little help trying to determine what was supposed to be under the fuel tank. There appeared to be a little soft material, possibly felt(?) under the periphery but really nothing in the well where the tank sits. There is a latitudinal rib near the front and just behind the opening for fuel cock, but seems as though there should be something that doesn't absorb water.
Does anyone with a T6 have any photos of this area from when they had the tank out? I did a search but really didn't find much about the T6, although there was info on T5's.
Thank you much for anything you can provide.
Bob

Geoff Fleming
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Re: What goes beneath fuel tank on T6

#2 Post by Geoff Fleming »

There is no material of any kind under the T-6 tank, simply some of the felting at the edges. You might consider investing in one of the many books which illustrate the 356 construction. I would contact Dr. Bill Block, of "Block's Books. He has a huge list of 356 related books, etc.
Since the tank sits quite high in the chassis, there is little chance of water penetration,( unless you drive through several feet of standing water).

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Jim Liberty
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Re: What goes beneath fuel tank on T6

#3 Post by Jim Liberty »

Robert, I believe Stoddard or Sierra Madre sell a self sticking felt for this application.
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Doug McDonnell
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Re: What goes beneath fuel tank on T6

#4 Post by Doug McDonnell »

Here is an old link: viewtopic.php?f=1&t=25409&hilit=gas+tank+insulation In the link Jack Staggs recommends nothing in that area although I believe T6B and early C had a felt type material there originally.
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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Jim Liberty
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Re: What goes beneath fuel tank on T6

#5 Post by Jim Liberty »

For a driver like my '63 - B, I use Black silicone dispensed from a caulking gun. Not enough to ooze out, but the to seal the metal to metal joint.
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Robert Reed
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Re: What goes beneath fuel tank on T6

#6 Post by Robert Reed »

Hi again guys; I can certainly understand the logic in placing nothing under the tank; hence my question. The crossing ridge though does create enough of a trough, that it made me wonder about the ridge area being an area of concern.
I will try to post a pic off this phone.
Thanks again,
Bob
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Jim Nelson
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Re: What goes beneath fuel tank on T6

#7 Post by Jim Nelson »

Here’s a picture of a ‘62 taken in 1977, when the car had a little over 19000 miles on it. Tank was out to replace that delightful sending unit for the fuel gauge. I don’t recall the nature of the material, but it sure looks like something is there.
45E45D50-71CE-4016-9476-9D1A4850C85F.jpeg

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Ron LaDow
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Re: What goes beneath fuel tank on T6

#8 Post by Ron LaDow »

Robert Reed wrote:Hi again guys; I can certainly understand the logic in placing nothing under the tank; hence my question. The crossing ridge though does create enough of a trough, that it made me wonder about the ridge area being an area of concern.
I will try to post a pic off this phone.
Thanks again,
Bob
Bob, if it were me (and even if I wanted to show the car), I would use an awl to open several holes 'upstream' of that rail (and coat the resulting 'tears' with the rust-preventative chem of your choice). And I would use generous fore-aft beads of RTV (with plenty of time to set) to keep the tank off that floor.
The factory had no interest in keeping the cars free of rust for any extended period and devoted little effort toward that end until sometime in the 9XX production. I don't blame them; they were making money by selling cars, not collectors' pieces, but we are pretty much in the latter business. And no one is EVER going to look closely enough to see what you did there.
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Eric McKinley
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Re: What goes beneath fuel tank on T6

#9 Post by Eric McKinley »

Robert,

The kit I bought from a vendor, may have been from Stoddard or Sierra Madre, it had a piece that folded under the tank as in the picture of the original above.

This material I am sure is not like the original, however it looks good under the hood and cushions the tank well, I could not see this stuff holding water or rotting any time soon, almost a type of fiber/plastic in consistency.

When the 4 clamps are applied to the perimeter of the gas tank it pulls it tightly down onto the material which sits under the edge of the tank.

This is the best picture I have of the material in place.
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Robert Reed
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Re: What goes beneath fuel tank on T6

#10 Post by Robert Reed »

Hi guys, Ron; I had the very same thought on the holes punched into the lowest area of the trough. I don't plan to show the car, as it will just be a driver. I thought maybe just 3 holes drilled, and then punched to assure that they would be lower than the surrounding area would be sufficient.
I will however check with SMC and Stoddard to see what may be available.
Thanks to all who responded, it certainly makes life easier for us amateurs.
Bob

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Mervyn Hyde
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Re: What goes beneath fuel tank on T6

#11 Post by Mervyn Hyde »

My 63 had cream/white felt strips along the raised ridges of the tank, that I put back in again, after cleaning and metal sealing.
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Robert Reed
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Re: What goes beneath fuel tank on T6

#12 Post by Robert Reed »

Hey, back again, Mervyn, your car must be RHD, as the front looks like a T5.
Well I was out in the garage digging around in the back corner of the tank well, and found what appears to be a black horse hair type of material sandwiched in tar paper. I may try to make something appropriate, if I can get a material that doesn't absorb water. I was going to go with Ron's suggestion and put a few drain holes in but after checking I think it would drain into the floor board. I'll see what I can find, Stoddard is asking over 3 bills for just the front...
Bob

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Re: What goes beneath fuel tank on T6

#13 Post by Ron LaDow »

Robert Reed wrote:Well I was out in the garage digging around in the back corner of the tank well, and found what appears to be a black horse hair type of material sandwiched in tar paper. I may try to make something appropriate, if I can get a material that doesn't absorb water.
Nothing I found was such that it wouldn't absorb (and hold) water, which is the reason I used beads of RTV, aligned to drain toward the front.
Robert Reed wrote:I was going to go with Ron's suggestion and put a few drain holes in but after checking I think it would drain into the floor board.
Look underneath. The T6 tank outlet is far forward of the interior. If it wasn't, when it rusted through, it'd leak on your toes anyhow
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Wil Mittelbach
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Re: What goes beneath fuel tank on T6

#14 Post by Wil Mittelbach »

As a reference:-
Herewith a photo of the original trunk and under tank mats of my T6 unrestored `65C cab.
(Disregard temporary water bottle/fuse cover bungees.)
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Mervyn Hyde
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Re: What goes beneath fuel tank on T6

#15 Post by Mervyn Hyde »

Robert Reed wrote:Hey, back again, Mervyn, your car must be RHD, as the front looks like a T5.
Well I was out in the garage digging around in the back corner of the tank well, and found what appears to be a black horse hair type of material sandwiched in tar paper. I may try to make something appropriate, if I can get a material that doesn't absorb water. I was going to go with Ron's suggestion and put a few drain holes in but after checking I think it would drain into the floor board. I'll see what I can find, Stoddard is asking over 3 bills for just the front...
Bob
Yes Bob - RHD 62-3 T6

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