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gasket material?

Hi all! if you've been following any of my posts I'm attempting to rebuild my boiler return trap and air eliminator. So I'll throw up a question, what type of gasket material should I be using for sealing the boiler return trap float mech. to the trap housing? What I pulled out looked to be an asbestos embedded fiber and/or graphite material total thickness 1/8". The return trap will be subject to full mainline pressure and temp. Choices I've found so far are:

1. Carbon fiber sheet gasket

2. Pure Rubber

3. High temp RTV (built up, let tack, then join, cure, then tighten)

4. aramide fiber sheet

I feel it needs to be 1/8" (what I removed) because the thickness will change the float level ever so slightly. There are several listed that are very pricey (without naming amounts) and some that are less, but the problem I'm encountering is that I need a small amount not a 60x60" sheet, more like 7"x 9". I did check with my local auto parts store and after viewing their sheet gasket material, I was not happy with the quality, and they could not provide any operating temps, expansion, etc. So any input would be great!
steam newbie


  • Rod
    Rod Posts: 2,067
    Original Steam Gaskets aren't Space Age Materials

    Hi- Without seeing the old gasket I'm not quite sure what to tell you. It would seem to me that considering the original age of the unit that the gasket material can't be too sophisticated which means you should be able to get by with some common automotive gasket material.

    Are you familiar with a cutting a gasket with a ball peen hammer? If not , Google "Cutting a gasket with a ball peen hammer" and you should get a lot of instruction on how to do it.  Basically the first step is to stretch the gasket material over the surface where you want it and attach the gasket material by making holes for several of the attaching bolts which then will secure the gasket in place while you cut it out with the ball on the ball peen hammer.

        You could also use  RTV to build a gasket. I would wax the cover surface where the gasket touches so that you can get the unit apart easily at a later time.

    - Rod
  • gerry gill
    gerry gill Member Posts: 3,058
    i like to use a product

    called Garloc (not sure i spelled that right)..as Rod says it taps out with a small ball peen hammer.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • moneypitfeeder
    moneypitfeeder Member Posts: 249

    The aramide (sp?) gasket is just the generic name for the brand Garlock. I was wondering if you got the marsh traps I sent you awhile back, just curious if either of them tested okay and gave you an accurate measurement of venting.
    steam newbie
  • gerry gill
    gerry gill Member Posts: 3,058
    oh, that was from you...thanks

    One was failed closed, and the other , well, lets just say for a vent thats made like a sherman tank, it vents like a martini straw..actually a matini straw would vent better..
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • moneypitfeeder
    moneypitfeeder Member Posts: 249
    should have included my "id"

    Sorry, didn't think about adding my "wall name" But I'm glad I changed over to the gordons, before I shut the system down for the summer the mains were venting beautifully with the new vents on them! I decided to go with 1/8" garlock sheet gasket for the return trap, might use it for the air eliminator (it's face plate cracked in half when I removed the piping to it and I had to have it braised), so I might use high temp RTV to build a more flexible gasket for that piece, and rubber composite for the transition from the return trap to the piping. Thanks for the updates on those traps, I thought they were toast, but I don't have anything rigged up to test them myself.
    steam newbie
  • World Plumber
    World Plumber Member Posts: 389

    If you use RTV coat one side with cooking spray. Makes for easy disassembly.
  • Al Letellier_21
    Al Letellier_21 Member Posts: 402

    Garlock makes a good gasket material and any good gasket supply house should have sheet material...if you use a gasket, coat it with a never seize product....it will be easy to replace the next time around....do the bolts too.....a can of this stuff should be in every steamfitters tool box.!!!
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