Hot Boat

I am currently using a Holley black pump but I am not getting enough fuel pressure at WOT. I reconfigured my fuel lines a few deferent ways but I cant get enough flow. A friend has a Aeromotive red pump that I can have. I know that these pumps are about the best on the market but they also push a lot more pressure than the Holley pumps.

Can my Holley regulator still work with this pump???? Or do I need a different one???

Also I do not run a return line back to the tank. is it necessary that I run one. If I don't have to I would rather not.

mcollinstn

The Holley regulator will work as long as it is one that does return fuel as opposed to a "deadhead" regulator (they offer both styles and I don't know which kind you have).

You "should" run the return all the way back but it is not an absolute MUST. If you choose to NOT run it back, then you should run the return fuel thru a cooler before it gets back to the tee before the pump. Heat is the main reason you should return to the tank.

There are also aftermarket pump controllers that run the pumps at varying pressures at different RPM that save on battery juice, pump wear, and fuel temp.

Dennis Moore

If you don't want to run a return fuel line you should use a high volume mechanical pump (Mark IV) or the stock mechanical Mercruiser pump that is belt driven off of the crankshaft. A mechanical pump will simply stop pumping when the needle and seats are closed and won't be effected by the dead head fuel pressure regulator (the life span of a mechanical pump is not shortened with a dead head system like an electric pump). If that's still not enough (you really need some larger needle and seats inside the carburetors) use the mechanical and an electric together. You will at least be able to get back to the launch ramp (on the mechanical pump) when the electric pump inevitably fails.
Dennis Moore

Raypanic

you can also run it back to the water separator if needed. It may be an easier connection.

Kanookstr

Aeromotive Does Not recomend running the return back to a "T" before the pump!!! They also do not want you you to return to the water seperator. Doing either of these will result in Pump Cavatation. This will result in either a Pump failier or Lean condition. Run the return to the tank using a 3/8" hose minimum. They also want a minimum of 1/2" supply line from the tank to the pump, But they prefer 5/8" line. That does not mean putting an adapter to the tank pickup to accomodate a 5/8" line. You must increase the draw tube in the tank as well, otherwise your still suppling the pump with the 3/8" draw tube. This Info I got from Brett himself at Aeromotive. If you do a search, I believe Blown1500 posted the Email with this info he got from Brett.
Good luck and don't take shortcuts. there to expensive

Dave F

Kanookstr is correct. I've talked to Brett at length about their pumps.

the best way is:
#10 in and out to reg.
use the return style reg. to the tank
#6 to each side of carb.
min of #8 return to the tank.
I personally used a #10 back to the tank to be assured that what ever the pump put out would be able to get back to the tank.
The pump runs best and draws less amps if it can run one speed constantly.
The reason you don't want it returning to the separator is because of heat, which will cause cavatation. The pump cools itself through the fuel it pumps. If you return it to the tank, it then cools the fuel back down.

Conversely, if you dead head the pump, (non return style reg) the pump draws more amp, creates more heat and shortens the life of the pump.

DAVE

Kanookstr

BTW HotBoat, Here is a link to the post I had last spring where I discribed How I increased my Tank draw tube size without welding a new bung to the tank. Drawtube size increase
Good luck

Krumbsnatcher

You mean something like this pump?

I did a whole project link with pics on oso on the install. I run the pump and a return line to my tank, recommended by Aeromotive. I will never have a vapor lock or run a lean condition. You will need to run this pump regulator setup, the holly's will not hold up to the torture.

http://www.offshoreonly.com/forums/s...ht=return+line

pm me if you have specific questions