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Gasoline vs gas carbs JC


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Old 04-16-2017, 07:47:28 PM
Crankpot Crankpot is offline
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Default Gasoline vs gas carbs JC

I was carefully inspecting my jc carburetor. Understand I know nothing except I've heard references to tri fuel carbs. My jc is set up to run propane. I removed the float bowl and looked inside. What I see looks like a gasoline carburetor with missing parts... main jet, float seat, float needle, float pivot pin, float.. there is a threaded in plug on the side of the carb where gasoline would enter..

Knowing all this do I have a carburetor that can be run on gasoline with the addition of the above listed parts?

Anyone know?
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Old 04-16-2017, 08:17:10 PM
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Billy J Shafer Billy J Shafer is online now
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Default Re: Gasoline vs gas carbs JC

That is a NG/LP carb. Which means you probably have a high compression engine.
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Old 04-16-2017, 08:25:04 PM
Handyhiker1 Handyhiker1 is offline
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Default Re: Gasoline vs gas carbs JC

Question on high compression pistons. What would the compression pressure be on high and low compression pistons in a JC? This would be as indicated by a compression tester.
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Old 04-16-2017, 08:32:40 PM
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Default Re: Gasoline vs gas carbs JC

To answer your question. Yes, add the missing parts and it will be a gasoline carburetor.

I would not run it on gasoline though. They do so much better on dry fuel, last longer and have far fewer issues. Less maintenance.
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Old 04-16-2017, 09:01:38 PM
Crankpot Crankpot is offline
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Default Re: Gasoline vs gas carbs JC

Quote:
Originally Posted by Gunny View Post
To answer your question. Yes, add the missing parts and it will be a gasoline carburetor.

I would not run it on gasoline though. They do so much better on dry fuel, last longer and have far fewer issues. Less maintenance.
I thanks. I don't know about the pistons yet but there is a silkscreen note on the housing stating the generator won't make the nameplate ratings on natural gas. Makes me think is has low compression pistons.
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Old 04-16-2017, 09:26:23 PM
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Default Re: Gasoline vs gas carbs JC

Crankpot, If you have or can borrow a decent bore scope, you can do a visual of the piston tops through the spark plug hole. Based on what you see (providing there is not huge amounts of deposits) you can determine if you go low or high compression pistons.

You could also do a compression test, but that is not always 100% reliable for determining low and high compression pistons for various reasons based on the health of your JC.

JohnnyC
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Old 04-17-2017, 09:08:33 AM
grif grif is offline
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Default Re: Gasoline vs gas carbs JC

Sometime in the last few months we had this exact thread with some pictures of available pistons and documentation that was interesting. I think OnanParts was involved in that thread, might try a search on his posts.



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Crankpot, If you have or can borrow a decent bore scope, you can do a visual of the piston tops through the spark plug hole.
JohnnyC
New Jersey
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Old 04-17-2017, 06:09:18 PM
Handyhiker1 Handyhiker1 is offline
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Default Re: Gasoline vs gas carbs JC

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Sometime in the last few months we had this exact thread with some pictures of available pistons and documentation that was interesting. I think OnanParts was involved in that thread, might try a search on his posts.
https://www.smokstak.com/forum/showthread.php?t=167523
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