Welcome! Becoming a registered user of ShortWingPipers.Org is free and easy! Click the "Register" link found in the upper right hand corner of this screen. It's easy and you can then join the fun posting and learning about Short Wing Pipers!

Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: Plug tester - worth the cost?

  1. #1
    smcnutt's Avatar
    Join Date
    Dec 2007
    Location
    Indianapolis, IN
    Posts
    1,339
    Post Thanks / Like

    Default Plug tester - worth the cost?

    Not sure why but my brother suddenly seems hell bent on buying a full blown spark plug cleaner/tester. Don't know if this is the exact unit he's looking at but at least something like this.

    Thoughts on the need to test plugs (we're using tempest plugs) using this pressure tester rather than the simple resistance test. He seems to think testing them under pressure would provide better feedback and be worth the cost of the tester
    “Common sense is in spite of, not the result of, education.”
    ― Victor Hugo

  2. #2
    Zac Weidner's Avatar
    Join Date
    Sep 2008
    Location
    Bunker Hill, IL
    Posts
    793
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    My opinion is you don't need the pressure testing that badly. I've yet to see an issue that showed up in the tester.

  3. #3
    Glen Geller's Avatar
    Join Date
    Dec 2007
    Location
    Beaverton, Oregon, United States
    Posts
    943
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    Tempest spark plus ~$25 each = $200 and they last about ten years @ 100~200 hrs/year.
    Spark plug tester ~$400.

    Buy new spark plugs every ten years.
    Glen Geller
    1955 PA22-150 "One For Papa!"

  4. #4
    Vagabondblues's Avatar
    Join Date
    Apr 2008
    Location
    N/A
    Posts
    526
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    I have seen small cracks that are not visible by visual inspection looking into the ceramic insulator with a magnifying glass. Most of the cracks are started during assembly when the shell is fitted over the threaded end and crimp sealed during assembly. After many heat cycles the cracks made during assembly will grow and propagate. The only way to test the insulating qualities of the ceramic is to "BOMB" test is on a machine. https://www.championaerospace.com/as...ical/72-10.pdf

  5. #5
    JPerkins's Avatar
    Join Date
    Aug 2014
    Location
    Cordova, Alaska
    Posts
    724
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    It does take more voltage to jump the gap under the pressure and turbulence that goes on in the combustion chamber than in open air. Therefore a plug that will spark in open air may not necessarily spark while underr load.
    Really the tester is only handy when your having a misfire and need to chase it down.

    Sent from my SM-G930V using ShortWingPipers.Org mobile app
    Jason Perkins

  6. #6
    Zac Weidner's Avatar
    Join Date
    Sep 2008
    Location
    Bunker Hill, IL
    Posts
    793
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    Perhaps spend your money on an engine monitor. That will tell you when you have a bad plug and which one. If you have a weak or bad one, throw it away.

  7. #7
    Administrator Steve Pierce's Avatar
    Join Date
    Nov 2007
    Location
    Graham, Texas, United States
    Posts
    12,054
    Post Thanks / Like
    Blog Entries
    1

    Default Re: Plug tester - worth the cost?

    I bought a similar tester used some 20 plus years ago and can't imagine life without it. From time to time I find bad plugs that were not identified any other way. There is no justification for tools, you just want them, buy them and use them.

  8. #8
    andya's Avatar
    Join Date
    Dec 2007
    Location
    UT47
    Posts
    1,610
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    sometimes when I'm too busy or lazy, I send a set of plugs to the shop in Van Nuys CA that cleans, gaps and bomb tests plugs.
    Only once did they find a plug that would not pass their tester. Doing that once or twice a year is a lot less $$$ than buying
    a tester. I believe Zac is correct that the engine analyzer will show the bad plug and you don't have to even remove it first.
    "Progress is our most important problem"

  9. #9
    Gilbert Pierce's Avatar
    Join Date
    Nov 2007
    Location
    Germantown, Tennessee 01TN
    Posts
    3,116
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    Quote Originally Posted by Zac Weidner View Post
    Perhaps spend your money on an engine monitor. That will tell you when you have a bad plug and which one. If you have a weak or bad one, throw it away.
    I agree with Zack. Unless you running a shop.
    If you only maintain your own airplane the bomb is a waste of money. Steve “appropriated” mine because I never used it.
    Last edited by Gilbert Pierce; 08-21-2019 at 10:00 AM.

  10. #10

    Join Date
    Aug 2012
    Location
    Kewanee, IL
    Posts
    36
    Post Thanks / Like

    Default Re: Plug tester - worth the cost?

    I found mine at a military surplus store brand new for $35 maybe 20-25 years ago. I asked the guy why it was so cheap and he said "nobody cleans car plugs anymore, they are too cheap to buy new." He didn't know it was for airplanes......(came with both 14MM and 18MM grommets.-Ross

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •