Bad Filler Cap Gaskets On Optimus/Primus Stoves

Discussion in 'Fettling Forum' started by Cookie, Sep 17, 2019.

  1. Cookie

    Cookie United States Subscriber

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    I recently purchased several stoves (96,210,00,45,& 51) and have noticed that every stove has a bad filler cap seal (dunk tested). Am I correct to assume that this is a common occurrence when finding older stoves that have not been rebuilt in say the last 20+ years ? Of course each stove has this or that part that is in need of replacement but the one common denominator is the bad cap seals. Oddly enough, the 51 does not have a screw in the cap and only fails after about four pumps where as the others fail immediately. It likes to tease you with a spurt of kero and then it's a dud with no pressure lol. I guess my second question to all is "Are caps without the screw directly in them inherently more durable?". Thanks
     
  2. snwcmpr

    snwcmpr Subscriber

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    There was some research done here a few years ago. I do not know the name of the thread. @Spiritburner probably knows, he did the research.
    The difference between different materials was noted. Viton (Fluoroelastomer) ended up being determined to be the best.
    I am not sure how long the other synthetic materials work. I have read here that cork can last a long time, and be refreshed if dried out.
     
  3. HaakonJ

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    On older stoves, you can assume most rubber seals are bad. Typically filler cap and NRV-pip on these types of stoves. They harden over time, and should be replaced. A new seal should last quite a few years, depending on the material they are made from. The Fettlebox make long lasting seals of good quality!
     
  4. Cookie

    Cookie United States Subscriber

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    I'll be making an order through fettlebox once I can figure out how much I need to order to justify the shipping charges lol. Right now I only need about $40 worth of stuff but the shipping is $20. Not really worth it as of yet.
     
  5. snwcmpr

    snwcmpr Subscriber

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    Make sure you use the discount code for Fettlebox.
    I have not seen shipping to be high.

    'Rubber' is a misleading word when it comes to our seals.
     
  6. Spiritburner

    Spiritburner Admin Subscriber

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    It's common on stoves rebuilt relatively recently. It's maybe not the best business model but Viton seals last for years. I've seals in use from 2011 that are still going strong. Before I used Viton I'd find seals rarely lasted a year. I have done soak tests on commonly available nitrile sheet & other 'kits' & non come close to Viton. I've had some washers disappear completely in 6 months. More commonly they just weaken or turn to mush.

    Shipping to USU is normally between £3.65 & £5.70. Sometimes the store does miscalculate the shipping but I always refund overcharges. If you message me here or send an email to the Fettlebox with your requirements I'll gladly quote you in advance. Plus, as a subscriber, you can access a discount code on this sites homepage for a 10% discount.
     
  7. Marc

    Marc Subscriber

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    How'd you spend $20 in shipping!? How much are you ordering? I sent an entire Coleman grill to Sweden for $24.

    Yes filler cap gaskets and rubber parts should be considered wear items. Note that like the rubber bits on a car, they keep aging even if the stove/car isn't used. A ten year old radiator hose is begging for problems, even if you only have a hundred miles on the car.
     
  8. Cookie

    Cookie United States Subscriber

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    @Marc I was going to order two sets of seals (FCAP1808) and the stove fettlers kit (SFKIT01) since I also need a small lead burner tank washer for one of the stoves (forgot which one atm) and would like to have the spares. The shipping was "Tier 5" so it was estimated at $20.

    @Spiritburner Thanks for the information. I may want some additional parts for my other stoves and since work has gotten in the way at the moment I have set the stoves aside for a few days. I'll place an order once I can give them all of my attention as I do not fettle when distracted. It's part of my zen lol.
     
  9. Spiritburner

    Spiritburner Admin Subscriber

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    On checkout that should come in at around $11. Bit more than I mentioned earlier as the bulk kits are parcel rather than large letter. The refill option would be less postage but the box is very useful.
     
  10. sa3spd

    sa3spd United States Subscriber

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    Hi,

    I think with the advent of Viton (and perhaps its generic clones?), we might be getting spoiled with the life expectancy of cap seals. Before I found this site--and Ross!--I went thru a period where all I could find to fit my caps was nitrile like you'd find at the hardware store. It would be gone in 6 months to a year. Now I've got two or three caps with seals probably nearing 10 years old and still working quite well. I'd guess about five years might be a good super conservative interval for replacements with Viton.

    Rick C