OMC small square fuel pump orientation

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OMC small square fuel pump orientation

Postby PugetSoundBoater » Sun Aug 13, 2017 1:31 am

On the side of these fuel pumps on the edge of one of the black plastic sections, there is a protruding tab with an arrow and the arrow has a "up" printed by it,the arrow should point up when mounted correctly. I have always assumed that these pumps must be positioned with this correct orientation to work right. I worked on a '89 Evinrude 15 hp i just got.It was mounted wrong,the arrow was pointing down. The pump worked fine.
Is this a big deal or not to follow the arrows mounting direction? Normally i do as i'm told..kinda :)
Thanks, Jim PSB
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Dan in TN
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Re: OMC small square fuel pump orientation

Postby Dan in TN » Sun Aug 13, 2017 8:50 am

The way I remember it (long time ago) that pump was used in several different configurations. It could be put together with the outlet in different directions. The up mark on the tab was so you won't put that section of the pump in upside down? That is how I understood it. I know we have people who have come up with good ideas of how to assemble those pumps. It helps a lot in putting them together.
The problem is I don't like the little pumps! Back in the day there was no little pump. They knew something back then. Today's fuels make it even harder for the little pump to do its job. Ethanol & oxgenated fuels vapor lock easier & the pump has to over come that. The bigger pumps have the ability to purge the air better. I try to avoid the small pump if at all possible. The big pumps are usually cheaper & do a better job. Sometimes you just have to get a little creative in finding the space you need for mounting. Thank goodness the hole spacing is the same!

Dan in TN

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Re: OMC small square fuel pump orientation

Postby Tubs » Sun Aug 13, 2017 12:08 pm

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Re: OMC small square fuel pump orientation

Postby fleetwin » Sun Aug 13, 2017 4:22 pm

Well, no need to argue with success....If it works, don't worry about....
But, I would follow the "up" indicators in the future when buying/installing these little pumps...

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Re: OMC small square fuel pump orientation

Postby johnyrude200 » Sun Aug 13, 2017 8:23 pm

My $0.02.

If the pump is working regardless of orientation, I suppose leave it alone.

However, make sure the little vent holes are facing down as it explains when rebuilding them in the directions. A lot of it has to do with how the pump is configured since there are like 4 different combinations (basically has to do with the outlet tube positioning).
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