Gx390 gas tank upgrade

I appreciate the help everyone!. I just ordered the part @marinegrunt posted.

Do you think what Marine grunt said will work? Like i said this isnt a big deal at all for me. I had originally tought there was a after market cap and you could just run a line to the top and gravity feed another tank to yours. Didnt really want to do a bunch of craziness lol.
Letting machine cool down and refueling is my lunch break anyways.

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Never know until you try

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If you went with the carb insulator you can install it. Just pull air filter housing, carb, pull off old insulator, and install the new with hose barb.

You also have to order a fuel pump. Any basic mower fuel pump should work. I can post a link for one if you like.

Iā€™ve only done the carb insulator on an 18 hp but see no reason why it wouldnā€™t work on a 390. Iā€™m 99.9% sure it will work just fine. If it doesnā€™t Iā€™ll order you a new valve cover, install a barb in it, and mail it to you. It only cost about $5 for one.

If you run into any issues when you install everything let me know.

Youā€™ll also need either some 3/16 or 1/4" fuel line too.

Iā€™ll snap some pictures of both the valve cover and insulator setup this evening.

I have some 1/4 fuel line. What pump do you think will work better and is known to be reliable? No need to send me anything if it doesnā€™t work lol. Do you think i need to order some gaskets too? My machine is practically brand new.

You donā€™t need any new gaskets since theyā€™re new. Give me a few and Iā€™ll post a link for pump.

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Just search this on Amazonā€¦Honda 16700-Z0J-003

It should work just fine. You could probably even find a similar pump local. Basically any mower fuel pump will work.

Some people even drill a hole in the crankcase to get a pulse. I donā€™t like the idea of that. I prefer the other 2 methods cause the valve cover and insulator are cheap to replace. No going back on the crankcase.

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Agreed ill update you when the parts come in.

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??? If youā€™re gravity feeding it you wouldnā€™t need the pump in the first place. Iā€™m confused lol

He means putting a pump on a machine that is supposed to be gravity fed might give it to much gas and flood it.

Itā€™s just a way to run a fuel pump so you donā€™t have to worry about mounting a bigger tank above the machine. You can mount the secondary tank anywhere you want on your trailer. I know it has nothing to do with washing but I had to do it for our golf cart when I threw an 18 hp engine in it. I got rid of the small gravity fed tank that came with the engine and used the golf carā€™s stock tank located on the side of the engine compartment. The only option was a fuel pump. I personally donā€™t know if the weight of more fuel would cause issues with the carb but guess it could. I just like the fuel pump so you you can install a bigger tank anywhere you want and donā€™t have to worry about it being above the pressure washer.

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Keep a fire extinguisher handy.

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I have one on my trailer.

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