Mercruiser 4.3 Fuel pump-oil sender question

[eclipse196]

It has been several years since being on this forum. Health issues kept me from finishing my welcraft restoration. I am now finishing everything, wiring, plumbing, etc. I have read a lot of discussions on the electric fuel pump, oil pressure switch wiring. I can't find a clear answer to this question. I have the three prong oil pressure switch and relay unit but want to know do I also need to have an oil pressure sending unit plumbed into the circuit or does the three prong switch work for both?
Any help is greatly appreciated.

 

[alldodge]

Welcome back
Need only the oil pressure switch for the fuel pump circuit

Would need a oil pressure sender for a oil pressure gauge, and gauge has nothing to do with fuel pump circuit

 

[eclipse196]

That was what I was wondering. The 3 prong switch is only safety for shutting off fuel pump if pressure is lost and then single post sender that would go to the oil pressure gauge on dash.
The 3 prong is not a dual pressure sender and safety switch for fuel pump?

 

[alldodge]

You can use a 3 prong or 2 prong just depends on how its wired

 

[eclipse196]

Thank you.