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AC 720 electric fuel pump conversion

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New member to the forum. I have a 720 that was stalling after 15-30 minutes use. I traced the problem to the fuel pump. Rebuilt the pump with an Onan kit but it still wouldn't pump. I had read some advice that recommended conversion to an electric fuel pump as an convenient fix. Got the pump, but can't figure out where to mount it. Pump instructions say to mount at least 12" below carburetor, but, as you know there's not much room there. Has anyone had experience mounting one on this model or can they recommend placement. Is the 12" guide a serious issue like ant-siphoning or can I mount it up on the shroud above the oil cooler?

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Welcom to our clubhouse, here's a tremendous amount of info at your disposal. I recomend you spend the 10 bucks to get access to the other areas of the club as there has been several posts on these Onan fuel pump convertions. I did a recent post on this but due to sediment in my tank stopping the fuel pump up I relocated the pump to the side below the tank and put the filter before the pump to help protect it. If your float and needle are working good then the height of the mount is not a problem as the tank is already higher than the carb. and it would siphon unless the carb. was in good shape. I used a NAPA fuel pump, with low pressure. I would recomend a fuel shut off velve like I put on if you suspect siphoning or just a precaution. I put this one on so I could get to it without raising the hood. Any further ? just let me know.

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The idea is to mount it lower or even to the bottom of the tank allowing it to pump only and not have to suck the gas out of the tank also. Gas will gravity flow to the pump then get pump to the carb. The pump will last longer and function better.

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