1991Johnson 70hp has electric fuel pump

[Joecm]

Hi, I've just purchased my first boat other than small tinnies. It came with `91 johnson 70hp and the previous owner has removed the whole vro pump assembly and basically just plumbed in a small electric fuel pump after the fuel tank that operates on a switch on the dash. The boat runs great in my test runs in the river but I don't like the setup and possible fire hazard. I'm wondering why the previous owner removed the vro whole system and went down this route instead of just going a non vro pulse fuel pump. I'm getting a pulse from the crank pulse limiter just not sure if the pulse is strong enough, how can I tell?
Please note I'm very new to outboards other than this forum for the last week..

 

[Joecm]

Hey guys this is my first post, I've been waiting for someone to reply but just realised I'm from Australia and it's late..
Haha thanks in advance

 

[racerone]

A simple pump is easy to install.------The pulse limiter ( flow fuse ) for the VRO is removed.-----Install a fitting there 1/8NPT pipe thread.----pump part # is 438557

 

[Joecm]

Hi racerone, your posts came up when I was searching for an answer a few times and excuse my newbieness it's been a quick learning curve the last few days, I haven't been able to see a photo of my outboard to compare with another so I'm hoping I'm understanding your information... 2 things, I'm so close to understanding what you say so I if I purchase a genuine omc #438557 fuel pump with 1 inlet and 1 outlet and tap the middle hole on the back of the fuel pump to install the1/8NPT pipe thread, then run a line to the pulse valve that comes out of the crankcase. 2 how much pressure pulse is needed to draw fuel as all I have to go on is I hooked up a tube to the pulse valve and I felt air blowing out at about 10inch...

 

[Joecm]

The pulse pulse valve that comes out of the engine was blocked with a basic rubber cap and cable tie.. This is why I question how much air pressure it needs to pump the fuel pump diaframe

 

[racerone]

STOP-----The 438557 pump is ready to install.----Do not modify it !------Remove the pulse limiter valve as it is not required for the 438557 pump ! ------Install a fitting for the pulse supply to the 438557 pump.----As found on say a 1983 model 70 HP.----Did this job last week and ultra simple it is.

 

[Joecm]

Wrong google picture of another hp model was throwing me with the pulse coming through the back of the pump directly mounted to the block ... So in my limited knowledgeable discription I remove the pulse limiter (flow fuse) from the bottom cylinder crankcase, screw in the the1/8NPT pipe thread, make a plate to hold the new 438557 pump and connect fuel in, out and pulse from the new thread . So no need to use the pulse limiter because crankcase combustion isn't an issue... Think I have it now hahahaha