Question for guru (Tech. params for Alpha and Bravo Fuel Supply)

[pmp1986]

Hi,
Does anyone have technical parameters (quantity of fuel supplied) for Alpha Fuel Supply module and Bravo Fuel Supply module.
As I understand Bravo supply much more fuel for the same engine.
Best Wishes,
Mikhail

 

[Bondo]

Ayuh,.... I take it yer talkin' 'bout Efi/ Mpi motors,..??

 

[pmp1986]

Ayuh,.... I take it yer talkin' 'bout Efi/ Mpi motors,..??

Yeap, exactly For example 6.2 MX

 

[alldodge]

There might be a reason why Merc shows different fuel pumps for the alpha and bravo for the 6.2L, but the amount of fuel difference would be negligible for the motor. My custom built 8.2L (520hp) uses the same fuel pump listed on the Alpha model. 861156A1

Maybe Fun Times might have some insight

 

[pmp1986]

As I see there is no other variants for 8.2L other than that pump. But engines with BRAVO/ALPHA in namecode have different solutions and that's surely not just for fun.

 

[Fun Times]

Below are the introduction notes when the Gen 3 first came out new in 2005.
I'm not completely positive, but I believe Merc didn't adapt the newer Gen 3 system to the Alpha system do to how the initial inlet cooling system is configured that may possibly put a water flow restriction to the cooling system for the Alpha drive configuration.
Cool Fuel System, Bravo

Service Notes:
EFI "Cool Fuel III" system introduced. Single integrated module filter, lift pump, high-pressure pump, pressure regulator and cooler all in one unit. Module mounted on right (starboard) side of engine [opposite side of engine from location of "Cool Fuel" II system]. It is positioned above and forward of the starboard front engine mount, for easier service access. This system will be standard on Small-Block MPI V8 Bravo, Small-block MPI Inboard, Big-Block MPI Sterndrives and Big-Block MPI Inboards (not available on V6 Sterndrive, SmallBlock Alpha and Small-Block Tow Sports).

Gen III Cool Fuel System System features:

Single Integrated Module - Filter, pumps, pressure regulator and cooler, all in one unit - Fuel flows through filter before getting to lift pump

More Reliable - Fewer components - Fewer fuel paths

Better Accessibility

?Production-Friendly? - Eliminates installation of separate pre-filter at OEM

Re-usable, consumer serviceable filter element - Pull element, dump water, re-install, continue voyage

This system will be standard on:
Small-Block MPI V8 Bravo
Small-Block MPI MIE
Big-Block MPI Sterndrive
Big-Block MPI MIE It will not be available on:
V6 Sterndrive
Small-Block Ski
Small-Block Alpha
System Overview
Water Separating Filter Element
2 pumps ? Lift & Pressure - Lift pump - Gerotor - Pressure pump ? Turbine
Fuel Pressure Regulator - New 288 kpa (~42 psi) regulator - O-rings seal between OD on regulator and ID in cover, rather than a face seal and return hose - Regulator dumps excess fuel to inlet side of pressure pump - Fuel pressure vs. flow characteristics differ slightly from Gen II, requires minor calibration changes
Internal Low Pressure Relief Valve - Limits pressure across lift pump to 10 psi +/- 5 psi - Dumps fuel to inlet side of filter.

System Module Features:
Dual Pump Configuration - Improved Vapor Lock resistance compared to engines equipped with current boost pumps
Corrosion Protection - Strontium-coated Internal water passage (same as outboards) - External housing e-coated
Engine Installation - Low profile water connection, disconnect as required during engine installation - 3/8 NPTF thread inlet fuel connection
Service Access - Modules located above front engine mount brackets in all applications
Water Jacketed - Parallel water flow through module permits smaller module
Pumps immersed in fuel and draw from bottom of cavity - Vapor rises to top of cavity, pumps always draw liquid - Reduced pump noise ? not audible over engine at idle
No external lines between filter, boost pump, pressure pump, and regulator - Eliminates 20 external fuel connectors
5 seals, not counting inlet and outlet - Filter cap ? Modified SAE o-ring seal - Module Cover ? Controlled-Crush quad ring - Pressure Regulator ? Diametric o-ring - Pressure Relief Valve ? Diametric o-ring - Harness ? Fuel-tight pass-through fitting
Self-Draining - Drains when seawater pump outlet is drained

 

[muc]

Now they have dropped the Cool Fuel III in favor of the FSM from the outboard side.