12abridgeport

Have been suspecting that my stock fuel pump was on its last leg for about 6 months. The car still drove but sometimes the only way I could get it started was to pour fuel right down the carb. The problem progressively got worse until a few days ago when I was driving back from work with the choke fully on just not to make the car stumble because of a lean condition.

So this weekend I installed Carter P4594 fuel pump with the Holley fpr. Pretty basic install really, kept the original wiring and return line is still intact.

First time I flipped the ignition key to ON I was expecting to hear the fuel pump prime but didn't hear anything to my surprise. After looking over the install everything seemed good.

I cranked the engine a few times and it didn't seem to want to start. Than I proceeded to pour fuel down the carb again and after a few rotations it fired up and ran strong. I still didn't hear the pump until I got the car fully warm and took it for a drive.

It drove and acted very well, my only concern is that I don't hear the fuel pump at all until it's above 1000 rpm in neutral or gear!

Not that I'm complaining but wanted to ask if that's normal or whatnot? Lol

Btw, the car is bone stock '84 gs with a stock Nikki carb.

Qingdao

iTrader: (3)

Have you bridged the little fuel cut off circuit near the steering column? I suspect that's what kept killing my Comp140 back when I was running it.

rxtasy3

iTrader: (2)

if that's the circuit i'm thinking of, it turns the fuel pump on after is senses oil pressure. so as long as the engine is running, so will be the pump. so can be bypassed no problem. although mine was bypassed at the control box in the pass floor by a friend so can't tell u what wires it is. but should be able to run just a single switched +12v from the fuse box to the pump and just ground the other wire, if there is one.

Toruki

Interesting. I have an 8383 GSL, and as long as the ignition is in running position, the stock fuel pump is whining away. I remember this same behavior back in the 80's with my long lost '83 GS.

So is the oil pressure cut off circuit an '84 and later kind of thing?

Siraniko

iTrader: (13)

you dont need to bypass anything since its a non-se. just connect the positive and negative wires. use a test light to make sure youre getting voltage to the pump.

12abridgeport

Yeah, that circuit under the dash was the culprit. I disconnected it and than jumped two wires and now fuel pump is on all the time the ignition is switched.

I followed this thread: https://www.rx7club.com/1st-gen-arch...uel-pump-relay

stranger

When i installed my pump, i just ran a dedicated/relayed +12v to the pump that is triggered off the trailing coil with ignition on.

As for having to pour fuel down the carb to start it, with the car off and you manually working the throttle linkage on the carb, do you see fuel squirt out of the accelerator pump nozzle? It will be in between the two primary venturis? Should see a short stream of fuel out of the nozzle down each primary venturi.

12abridgeport

The problem is resolved, but yes I did see the fuel squirt while there were still some left in the line. The new fuel pump made a huge difference in drivability, sounds and feels so much smoother now