I need a very good membrane

For the project truck, I find myself with an odd problem. I have two tubes protruding through the wheeltub. I wish to somewhat isolate the large hole in the wheeltub from road debris, but I need the membrane to be easily removable. Basically, I need duct tape that I can form into a membrane that I can rivet onto the wheeltub and not be a hack about it.

Ideas?

Shifter boot?

A sheet of rubber? The stuff they use for membranes roofing is great if you know any roofers and can get your hands on some scrap.

Look up 'pipe portal'

Or how about a clamping CV joint boot?

what about a wheelbarrow inner tube?

Aw crap! I just helped a buddy lay down some roofing membrane. 40 mil thick IIRC. TOUGH STUFF. He had a BUNCH of scrap left over. Give me your sizes and I will see if I can score some pieces.

Elephant condom?

Could you reuse the firewall boot from... something? On my C900s, there is one that surrounds the shifter shaft as it passes through the firewall. It is held in place by the lip on the firewall.

I am not sure about any of these yet/ The application is two tubes, one 2 1/4" and one 3/4" protruding through a square hole roughly 5"x4".

Maybe something like these?

http://www.sealsit.com/firewall.asp

Curmudgeon wrote: Maybe something like these? http://www.sealsit.com/firewall.asp

Looks good, but pricey. I might DIY something just like it, though.

Mudflap material.

Pond liner. And you can mimic what curmudgeon shows with a sheetmetal rings around the perimeter. Cheap and available. The roof membrane will also work.

Since I know $$$ is always a factor, might also be worth looking in the carpet runner section of the Home Depot. Buy it by the foot instead of the roll.

If you need to get real fancy, you can order some liquid casting material and make a mold of what you want. Some of the materials are very tough when cured.

That roofing material is good stuff, always keep some handy around the shop. 101 uses. Use it under jaw teeth wrench to not mar the surface too.

There's industrial rubber gasket material in rolls/ sheets, some reinforced w/ fiber. 1/8" would be good for that type of application, won't flex as much as roofing material. Somebody in a plant or mill oughta hook ya up.

Little silicone around the tube to membrane seam helps (Watch yer hootus).

NOHOME wrote: Pond liner. ... The roof membrane will also work.

Hint: it's pretty much the same stuff.

Go to big box home store of choice and look for pipe boot flashing.

I had a couple of holes that needed isolation and used a plastic trash can as a donor. Easy to cut, molded it a bit with a heat gun, paint and VIOLA...perfect fit. I even put a grommet in it for some wires and hot melted some washers in the screw holes.

I did drag home a couple of roof membrane (Mule Skin) that has become many things such as lower shifter boot.

Bruce

The roof membrane everybody is talking about is EPDM, by the way. Typically available in 40 mil, 40 mil reinforced, and 60 mil. I'd skip the reinforced stuff.

How good of a seal do you need? Does it need to be flexible, or is a little freedom of movement enough? Could a solid piece of sheet be cut to fit close on the tube(s) and larger than the hole, then positioned closely against the wheel tub?

Just spitballing ideas, since I am unable to see the application or know what the other requirements and constraints might be.

In reply to Driven5:

I just need the cavity above the wheeltub not to be filled with trash and dust. The tubes I am sealing are protruding from under the wheeltub and into a faux stake pocket. I don't want the faux stake pocket to get ridiculously filthy. We're not talking water tight.

The hardest part is that I have to decide to make it reusable or not, because the tubes have a flexible hose on each end to connect them, and the hose will need to be pulled down through this membrane due to space constraints to remove the tube.

Then again, how often do you need to maintain your fuel filler?

Insane

tuna55 wrote:

Curmudgeon wrote: Maybe something like these? http://www.sealsit.com/firewall.asp

Looks good, but pricey. I might DIY something just like it, though.

Price is always an issue for me, cheap is best. Shoot, head to the boneyard and start looking around. Firewall harness grommets for wiring, the aforementioned steering shaft boots, there's all kinds of stuff out there. Something is bound to fit.

JohnRW1621 wrote: Insane

and that's why I can't say membrane

thanks, now stuck in my brain all day

Here, this will help:

Doesn't the Miata have something like this where the fuel tank fill and vent penetrate the trunk floor?

I'm fresh out of miatae or I would just look.