the right compression tester for mopeds<<<<<<<<<<<<<

Ryan Mayer /
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I was scratching my head for a couple days as my combustion chamber cc measurement and math were not coming close to what my compression gauge was saying. Changed pistons, changed rings, changed cylinders, even checked the gauge against an air compressor, finally borrowed a tester..... still reading low. I was about to deck my head some more, then it hit me

^this kind is the wrong kind to use on a small displacement engine. The hose attached to the gauge has a schrader valve at the coupler but the detachable hose that screws into the head has no valves in it at all. Therefore the detachable hose has to be counted as combustion chamber volume. No big deal on a large engine but when you're dealing with a combustion chamber of around 4cc's it greatly affects what the gauge shows.

^So I dug out one of these, took off the rubber thing, gutted a sparkplug and soldered the sparkplug remnants to the compression tester. Schrader valve now sits where the electrode would go and combustion chamber volume is dead on. Gauge now shows 150% of what it was reading before.

So before you go decking your head and seizing your engine make one of these up to throw in your tool box. Takes about a half hour and only took a propane torch and some solder.

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Subject Written By Posted
  the right compression tester for mopeds<<<<<<<<<<<<<Topic by: Ryan Mayer Ryan Mayer 09/27/11 05:24AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Heath Daniel Heath Daniel 09/27/11 11:26AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Mars   Mars   09/27/11 11:28AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: JBOT Admin JBOT Admin 09/27/11 12:13PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Flagrant - Flagrant - 09/27/11 01:13PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Joey P Joey P 09/28/11 12:38PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Rachid Z Rachid Z 09/27/11 02:40PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Tim Mohr Tim Mohr 09/27/11 02:53PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: john doe john doe 09/27/11 08:38PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 09/28/11 02:16PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Ryan Mayer Ryan Mayer 10/17/11 07:32AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Heath Daniel Heath Daniel 10/17/11 11:18AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Maciek Dub Maciek Dub 05/20/14 02:44AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 10/17/11 12:03PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: cheetahchrome . cheetahchrome . 10/17/11 12:15PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Ryan Mayer Ryan Mayer 10/17/11 01:05PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 10/17/11 03:12PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Flagrant - Flagrant - 10/17/11 03:28PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: mit mortso mit mortso 10/17/11 06:12PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: K Olena K Olena 10/17/11 09:02PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 10/17/11 09:48PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Ross Maser Ross Maser 10/17/11 10:15PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: derek from black pipes moped gang 🌧 derek from black pipes moped gang 🌧 10/18/11 09:33AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: mit mortso mit mortso 10/18/11 06:11PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 10/20/11 01:48PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Ryan Mayer Ryan Mayer 10/20/11 04:28PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Road Rash Dave Road Rash Dave 03/06/13 07:57AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Born to be WillD Born to be WillD 03/06/13 01:17PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Graham Motzing Graham Motzing 05/20/14 10:15AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Maciek Dub Maciek Dub 05/20/14 01:34PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: Ryan Mayer Ryan Mayer 05/21/14 09:36PM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: mit mortso mit mortso 05/22/14 10:15AM
  Re: the right compression tester for mopeds<<<<<<<<<<<<<Re: matt boda1nz matt boda1nz 05/22/14 10:26AM

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