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Onan 12.5jc water in fuel


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  #1  
Old 06-04-2013, 07:00:24 PM
rodymartin rodymartin is offline
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Default Onan 12.5jc water in fuel

The grandkids left the top off the gas tank and it now has water in the carb. what is the best way to deal with this?
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Old 06-04-2013, 07:30:35 PM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5jc water in fuel

Tell your son/daughter to make sure grandkids leave your stuff alone.

Drain the tank, remove the carb bowl, and flush the lines as best you can. Put back together and add a small amount of fresh fuel. Run the set, expect it to stumble and sputter a little bit at first. If it runs OK, fill the tank. Secure gas cap so grandkids can't fool with it.


Save the water contaminated gasoline in case you need it for son/daughter's car in case they fail to get the message across effectively to grandkids.
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Old 06-04-2013, 07:49:52 PM
rodymartin rodymartin is offline
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Unhappy Re: Onan 12.5jc water in fuel

Quote:
Originally Posted by Wayne 440 View Post
Tell your son/daughter to make sure grandkids leave your stuff alone.

Drain the tank, remove the carb bowl, and flush the lines as best you can. Put back together and add a small amount of fresh fuel. Run the set, expect it to stumble and sputter a little bit at first. If it runs OK, fill the tank. Secure gas cap so grandkids can't fool with it.


Save the water contaminated gasoline in case you need it for son/daughter's car in case they fail to get the message across effectively to grandkids.
How to get the carb bowl off with out taking the carb off?
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Old 06-04-2013, 08:16:50 PM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5jc water in fuel

For the (spec AA) JC I have, the carb bowl is held on by the main jet. Removal is very simple - screw out main jet needle, place in a safe area. Loosen and remove the main jet, and the bowl will come right off.

Yours may be different.
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Old 06-04-2013, 08:55:04 PM
rmchambers rmchambers is offline
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Default Re: Onan 12.5jc water in fuel

Can you remove the whole jet assembly without messing with the main jet? that would be easier than having to re-lean the mixture again.
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Old 06-04-2013, 09:08:34 PM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5jc water in fuel

You can, but I have broke a needle valve off before by doing so; thus, I do not do so now.
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Old 06-04-2013, 10:25:06 PM
len k len k is offline
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Default Re: Onan 12.5jc water in fuel

I don't know your carb , but all the carbs I played with are easier to remove and clean them in your hand. Less chance of bending things, like the float. Plus if you just take it off you can also disassemble it more to give it a good cleaning. Carbs always seem to need a little cleaning.
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Old 08-03-2013, 01:19:07 AM
rodymartin rodymartin is offline
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Default Re: Onan 12.5jc water in fuel

Quote:
Originally Posted by len k View Post
I don't know your carb , but all the carbs I played with are easier to remove and clean them in your hand. Less chance of bending things, like the float. Plus if you just take it off you can also disassemble it more to give it a good cleaning. Carbs always seem to need a little cleaning.
Cleaned the carb and reassembled it. completely draned the fuel system. Now it runs better than ever did. But I have a electric fuel pump to keep it running. Where is the best place to hook up the wire to shut it off when I shut off gen set?
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Old 08-03-2013, 06:22:52 AM
Gunny Gunny is offline
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Default Re: Onan 12.5jc water in fuel

Pick up power for it on the hot side of the ignition coil.

Coil has (3) wires. One is the high voltage cable to the middle of the distributor, another small wire runs to the side of the distributor. One wire runs from the coil to the control box. Use that wire as the power source for the electric fuel pump.
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