87 Sentra Fuel Pump

Glacophane · Apr 19th, 2004, 09:16 PM

I'm buying an 87 sentra that needs a new fuel pump..I was wondering is it possible to put an electric fuel pump on the 4.0 liter engine? The reason I'm asking is because I have it currently in the shop. The mechanic tells me that it needed a fuel pump, but whatever it is that connects to the arm of the fuel pump is lying flat. I dont really know that much about cars and dont really know what this guy is telling me either. He called it the cam lobe but I dont see how its possible that this would connect to the fuel pump.

minute rice sentra · Apr 19th, 2004, 09:24 PM

yeah, that's the fuel pump cam, I guess that's what it's called, but I don't see how it could be "flat"??? I would think an electric fuel pump could be used but you might have to do alot or "rigging" to make it work good, (ie: pressure regualtor, wiring, etc...)
I would just try to find a factory replacement(new or salvage) if I were in your shoes, there aren't really many gains to be had by going electric in this case.

Dean GXE · Apr 20th, 2004, 06:56 AM

Did any carburated sentra have an electric fuel pump?
What about fuel injected models? I am looking for an electric fuel pump that delivers 4psi of high volume flow.

Myetball · Apr 20th, 2004, 04:41 PM

Quote:

Originally Posted by Glacophane

I'm buying an 87 sentra that needs a new fuel pump..I was wondering is it possible to put an electric fuel pump on the 4.0 liter engine? The reason I'm asking is because I have it currently in the shop. The mechanic tells me that it needed a fuel pump, but whatever it is that connects to the arm of the fuel pump is lying flat. I dont really know that much about cars and dont really know what this guy is telling me either. He called it the cam lobe but I dont see how its possible that this would connect to the fuel pump.

Wow, how'd you get a 4.0 liter engine in a B12?

It's really a 1.6 liter. The part you are talking about is called the Jack Shaft. It's a smaller shaft in the block that has a lobe on it that drives the fuel pump. The actual Cam Shaft is in the head.

Gonna have to take all the crap off the front of the engine to get at it. May want to consider getting a new water pump, timing belt, and front main seal installed while it's apart.

minute rice sentra · Apr 20th, 2004, 06:03 PM

Quote:

Originally Posted by Dean GXE

Did any carburated sentra have an electric fuel pump?
What about fuel injected models? I am looking for an electric fuel pump that delivers 4psi of high volume flow.

The carbs had a mechanical fuel pump and the TBI's had an in-tank electric pump, I found something that to me seems strange, in my '88 FSM it says "the pressure regulator, built into the side of the throttle body, maintains the fuel pressure at 43.3 psi." on page EF&EC-18 and then on page EF&EC-149 for the fuel pressure check procedure it says "At idle speed: Approxmately 34 psi" so either way it will easily support 4 psi, you just need an adjustable regulator, but I don't know how volume it's supposed to flow.

Quote:

Originally Posted by Myetball

The part you are talking about is called the Jack Shaft.

Right on the tip of my tongue!

Gsolo · Apr 20th, 2004, 11:09 PM

since you mentioned jack shaft...does the TBI have it? i was thinking it also ran oil pump does it not?

sorry,not trying to steal thread.

the electric fuel pump from TBI is probably to much volume, and a regulator is very expensive. if you must go to electric fuel pump...look at summitracing for part number CRT-P4070 Dont let the fact that V8's were in mind for the pump, it doesn't care what its feeding

In case you are wondering its 5psi at 72gph for $59.95 you'd probably have to wire it into your ignition somehow...not sure how'd you wire it in.

Myetball · Apr 20th, 2004, 11:15 PM

Yeah, all E16's have a jack shaft. There's a gear on the shaft that runs the oil pump and a cam lobe that runs the fuel pump.

Are you looking at an electric pump to avoid replacing the jack shaft? If/when you replace it and if you replace the fuel pump, you shouldn't need to worry about it for years.

AVERAGE · Apr 21st, 2004, 04:43 AM

hey myet, i was told if u did this that u had to leave the mech pump in place and just fab a bracket up for the electric one and hook up the lines. i looked into it for awhile before my car totally died but never got around to doing it. if i remember correctly , it was like 40 bucks at autozone.

Myetball · Apr 21st, 2004, 06:13 AM

You could remove the mechanical pump by fabricating a plate to cover the hole.