90 model Merc 454 Mark V

[Speakrdude]

I am rebuilding the above referenced engine to drop in a 23' Maxum open bow with a Bravo 1.
My intentions are to install an electric (Airtex-Marine) fuel pump and simply "Block-off" the raw-water-pump mounted, mechanical fuel pump.
Anything wrong in my thinking? I intend on connecting the fuel pump through the low oil psi switch.
Does there need to be any delay timer installed for the initial key-on for the fuel pump to run for a few seconds with -0- oil psi or will simply cranking the engine to build oil psi suffice?
Any pointers are always welcome!

 

[Bondo]

I am rebuilding the above referenced engine to drop in a 23' Maxum open bow with a Bravo 1.
My intentions are to install an electric (Airtex-Marine) fuel pump and simply "Block-off" the raw-water-pump mounted, mechanical fuel pump.
Anything wrong in my thinking? I intend on connecting the fuel pump through the low oil psi switch.
Does there need to be any delay timer installed for the initial key-on for the fuel pump to run for a few seconds with -0- oil psi or will simply cranking the engine to build oil psi suffice?
Any pointers are always welcome!

Ayuh,.... Yer headed the right way, but there's no time delay relay, ya just run a wire from the outside tiny terminal on the starter's solenoid, to power the pump, when the starter is engaged,...

 

[alldodge]

Here is a pic

 

[Speakrdude]

Easy Peezy

 

[Speakrdude]

So it looks like I need to add a "second" low oil psi switch. The first one goes to the alarm system, and I don't see how I could make it operate both, without adding some electronics to it.

 

[Bondo]

So it looks like I need to add a "second" low oil psi switch. The first one goes to the alarm system, and I don't see how I could make it operate both, without adding some electronics to it.

Ayuh,.... The alarm switch, goes to ground when the oil pressure drops to 'bout 3 psi,....

You need a switch that passes through voltage when to oil pressure gets up to 'bout 3 psi,...

 

[Idlespeedonly]

Speakerdude, I sent you a message.

 

[achris]

The problem with using the alarm oil pressure switch (and it can be done very simply with just a SPDT relay) is that if you get an alarm condition on either over temp or drive lube monitor, it will shut the fuel pump off. And that may or may not be desirable... depending on the circumstances....

Chris.......