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Komatsu FG25ST-12:
No start - vacuum issue

Let me start by saying I am in no way a mechanic but I know enough to get myself in trouble lol.

I have a 2000 Komatsu FG25ST-12 with a propane Nissan engine. I had issues with the machine starting but immediately shutting off. I had my mechanic come onsite for a brief look and he suggested a vacuum issue and to change the LPG converter. I changed the converter module as well as the lockoff module. Hooked everything back up and still same issue. If I disconnect the vacuum hose on the converter and suck on it while turning over it fires right up, then shuts off again as soon as I stop.

Obviously I have a vacuum issue but I'm not certain where to go from here and am trying to minimize my mechanic call out bills. :)

Thanks in advance for any feedback/help.
  • Posted 19 Jan 2022 09:03
  • Discussion started by PETER
  • Alberta, Canada
- PETER
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Showing items 1 - 2 of 2 results.
Hello Peter, control the governor. It's mounted below the carburator and it's got a 3 screws cover, inside there's a spring witch controls the maximum RPM. I think the spring is broken and the valve stays closed.
Regards
Marcb
  • Posted 22 Jan 2022 01:00
  • Reply by marcb
  • ANTWERP, Belgium
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I would look at carb make sure plunger inside is moving when cranking if stuck will not allow any propane to converter hope this helps
  • Posted 21 Jan 2022 02:47
  • Reply by Scott_
  • Pennsylvania, United States
Scott
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The now-ubiquitous 'Keep Calm and Carry On' phrase was coined by the British government in 1939 to encourage its citizens to stay strong. Posters with the slogan were printed but never officially issued and only unearthed in 2000.