Replacing a single-piece cap gasket the Hippie way.

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Gunhippie
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Replacing a single-piece cap gasket the Hippie way.

#1

Post by Gunhippie »

Lots of us dread this procedure. There's a good reason Coleman Service Centers just tossed the cap and put a new one with fresh gasket on. But we want to keep our painted caps that match the founts, right?

So here's how I do it:

First, of course take the cap off the fount and turn it gasket-side up. Now get a hand drill and a 1/8" or slightly larger drill bit. Carefully drill a series of holes around the circumference of the old gasket, being careful not to drill into the metal of the cap, just through the dried-out rubber.

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Now use a jeweler's screwdriver and/or gasket pick to pry out the little chunks that are between the holes.

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That's never happened to me before. Normally, the gasket comes out in little, brittle chunks. I guess it means the gasket was fine and didn't need replacement--but that's something I do on every fettle, regardless.

Clean the groove where the new gasket will go, making sure you leave a clean, flat surface.

You can buy new gaskets from OCP or E-Bay, but I make my own.

A concentric punch set is almost indispensable for making concentric gaskets. Good luck trying to get a nice, uniform ring without one. My Mayhew set was spendy, but has paid for itself many times over, both at work and on fettles.

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According to my notes, a single-piece gasket is 3/4" OD by 7/'16" ID X 1/8" thick. Now the problem with that is that the two punches fit on the same step of the mandrel, meaning I can't punch them in one fell swoop. But I have a trick for this.

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Mount a 1/8" punch to the center of the mandrel, then the 3/4" for the OD to the first step.

Punch out a slug the size of the OD with the 1/8" hole nicely centered in it. I'll be using 1/8" thick Viton 70 sheet for this.

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An old scrap of plastic cutting board is excellent for making gaskets. I put it on the concrete floor, as even my uber-stout workbench has too much bounce to get a good. clean punch.

Now remove the 3/4" punch and back the 1/8" out a couple of turns until it projects past the edge of the 7/16" ID punch:

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That center punch needs to come out a turn or two, until the straight part just clears the ID punch.

Now skewer the OD size slug on that projecting 1/8" punch and punch away.

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Of course, since this was the 275 from Hell fettle, the center hole isn't big enough. The centers of the single-piece caps are peened over and there is some variation, so I started over and made a gasket with a 3/4" OD and 1/2" ID. It fits perfectly.

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I use a small finishing nail set to push the gasket into place, after lubing it well with silicone plumber's grease. Work the outer edge in first, then get the inner edge tucked under the peened center bit.

I've never had one of these fail, but it's always a great idea to test it using soapy water and a pressurized fount. Safety First!

TFL!
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Walk a mile in a man's shoes before you criticize him--then you're a mile away, and he has no shoes.
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stoves1234
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Re: Replacing a single-piece cap gasket the Hippie way.

#2

Post by stoves1234 »

Great idea Timm. You're right, compared to removing the gasket from a three-piece cap I do dread working on the one-piece caps.
Jim
stoves1234
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Re: Replacing a single-piece cap gasket the Hippie way.

#3

Post by stoves1234 »

Great idea Timm. You're right, compared to removing the gasket from a three-piece cap I do dread working on the one-piece caps.
Jim
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outlawmws
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Re: Replacing a single-piece cap gasket the Hippie way.

#4

Post by outlawmws »

Having cap jaws for a vise helps hold the cap without danger to your hand/fingers - I made this out of scrap Maple.
Cap and insert block e.jpg
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Gunhippie
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Re: Replacing a single-piece cap gasket the Hippie way.

#5

Post by Gunhippie »

But those are three-piece caps. I just remove the insert and burn the gasket out!
It's priceless until someone puts a price on it.
Walk a mile in a man's shoes before you criticize him--then you're a mile away, and he has no shoes.
Texan's last words: "Y'all--hold my beer--I wanta' try sumptin'."
Timm--Middle of nowhere, near the end of the road, Oregon.
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outlawmws
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Re: Replacing a single-piece cap gasket the Hippie way.

#6

Post by outlawmws »

The cap pockets can still hold one piece caps, and Its still easier for the final scraping with the three piece.
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Coleman Blue's 243's #341 - 275 Appreciation Syndicate member 0242
FAS #001 Confusing Future Generations of Collectors, One Lantern at a Time!

“A Human Being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, give orders, take orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook  a tasty meal, fight efficiently, die gallantly.  Specialization is for insects.”            - Lazarus Long


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