vac fuel pumps

[Fast Fred]

wanted to run twin vacuum pumps on an OMC, wanted to know how everyone runs theres,
do thay run two pumps on the same cyl, or should i make an other vac barb on another cyl so each pump pulses on its own cyl.
thanks
FF

[Powerabout]

definately one pump per cylinder

[Fast Fred]

ya was thinkin that, all factory pumps are set that way, thanks, anybody gots any pic?

[Powerabout]

and run the fuel flow in series

[17W]

This engine uses 2 fuel pumps, one was for bring fuel from the fuel supply, the other to deliver fuel to carbs via the oil mixing unit.

Maybe J. Nerstrom will chime in on this.

[Fast Fred]

so drilled in on number two intake on the linkage side, ( theres a threaded boss for a dashpot, used the hole closest to the crank). so not side by side? was thinkin fuel line in to a Y fittin then into the pumps, then from one pump to a Tee between the top and the center carbs, pump two Tees in between the center carb and the lowest carb. lookin for volume to the carbs, seen this set up on a V6

[Tim Kurcz]

Hey Fred,

There are two set-ups you can use.

1) The puller & pusher pump set from an OMC 30 or 35 HP triple work well. These are piped in series to the fuel manifold. Or,

2) Two standard pusher pumps piped into a common fuel manifold one from each end.

In both cases pumps are run individually from different cylinders. I've used these systems for race boats with electrics deleted for weight savings.

Good luck,

Tim

[Fast Fred]

finger ported, solid molded, SST60, i'm going with one on each end of the manifold.

[Bill Gohr]

finger ported, solid molded, SST60, i'm going with one on each end of the manifold.

On a 3 cylinder? How many Lbs. of fuel do you need for 100hp?

When I ran the 2.6GT's (V6), I used, as many did, what we called half a VRO which is a South American 200 (3.0L) fuel pump, spun 8300RPM, no problem..................

[Powerabout]

a cross flow big bore to 8300..wow!
and about 10gph so less then 10lbs/hr