Fuel pumps

[RumRunner]

Hi !!
Just wanted to make sure I had some info correct before I started tearing into this old crossflow. I am pretty sure I have read every word that you guys have posted on the crossflow motors. And for those of you that have posted this info a big THANK YOU !!.

Fuel pumps-- From reading the posts I gather that when switching to an electric fuel I can do away with the stock pumps on the motor ??

Is this correct ?

Thanks

[Jeff_G]

Yes, what size motor?
In most situations you would be better off using the diaphram pump with the motor. An electrical fuel pump only adds something else to wire, break or fail. You also have to regulate the pump to the carbs so as not to flood.

[RumRunner]

It's a 1978 235
How would i go about regulating the fuel pressure between the 3 sets of carbs ?
Or would I just regulate it comming out of the pump and all 3 would be at the same pressure ?

Thanks

[Talon2.5]

i would regulate the pressure down at the pump

[Markus]

You put the regulator somewhere between the pump and where the fuel line forks into the the lines going to the carbs.

With many pumps, such as the Carter pump that I am using, and the smaller Holley pump (the red one, if I remember correctly), you do not need a pressure regulator.

While you are at it, get a fuel pressure sender and gauge as well. I know Autometer and Gaffrig sell them, but I do not believe that Teleflex and the other cheap marine gauge people do.

Be aware though, that although you do not need to worry about primer bulbs and broken diafragm pumps, the downside is that electric fuel pumps make some noise.

[B.Leonard]

Use an electric. I've used 2 different red pumps on two different 235s. No regulator needed.

Ask yourself this... Why would I use the same fuel delivery system that's on a 9.9hp kicker on a 200+hp performance outboard?

Wire it into the ignition and kill switch. When you start the motor, you know you have 5-7psi instantly and at all times. No bulbs to squeeze :p

-BL

[RumRunner]

Thanks for clearing that up for me !!
Will definatly go with the holly red wired to the ignition.
Thanks for the help :)

[BenKeith]

Carter also makes a pump that requires a regulator. If you get their larger model. Both companies also make pumps that will work without regulators.

As for regulators Carter (theirs is made by Holley) and Holley have one that can be use down stream at the pump or as a bypass regulator.

I find that you maintain a much more consistant fuel pressure by making a fuel manifold and using it as a bypass regulator on top of the manifold set so I have 5 - 5.5 pounds at the carbs at WOT and the 11 - 14 pound pumps. Doing this keeps the pump from having to deadhead. The pump is pumping wide open and all unused fuel is being sent back to the tank (you do have to run a return line back to the tank), just like the fuel injection system do, and the pressure in the manifold is being maintained at a constant.

I know most people here seem to like the Holley blue pump, but I have for many years found I get much better service from the Carter pump. I discovered this years back during may car racing days. The Carters just don't seem to fail and they don't lock up after setting for a few months like the Holleys always did.

Both companies have pumps that will deliver almost 100 gph at 7 pounds or almost 100 gph at 11 - 14 pounds

Figuring this is over twice what your motor is going to burn, you shouldn't have a fuel starvation problem.