nitsua93

iTrader: (2)

My 1980 RX7 (SA22 12A) receives consistent fuel into the 2 main barrels consistently at low RPM. When revving just one barrel receives consistent fuel. I've noticed that my fuel pump constantly clicks even when the engine isn't running. The pump constantly will push fuel without the engine on. I know that because I pulled a fuel line on the firewall and then the 2 that go to the carb barrels. I don't know if the pump relay is bad or if the pump itself is bad. I changed the fuel filter and it did not seem to change anything. Plenty of fuel seems to run to the carb. I've probably cleaned the carbs as much as I can without pulling the carb off the motor. When driving it feels like I receive power again around 4K RPM. It does not matter whether I rev it up slowly and feather it or if I just floor it. I do not believe any lines to be clogged, the original fuel filter was in good shape and fuel pumps good at the lines under the hood. The car also only has about 35K miles

Another thing I could add is that I bog out at 3K RPM, then somewhat kicks back in at 4K RPM. It idles pretty well besides a miss every now and again. I probably need new plugs and wires.

diabolical1

iTrader: (3)

welcome.

what carburetor? what pump? i just want to be sure whether you're speaking of a Nikki and stock-ish pump or not.

also, i'm not 100% certain your 1980 has a factory relay. i think they came later - maybe '83 or '84? i'll have to check on that though.

nitsua93

iTrader: (2)

I couldn't find a relay. So I'm not sure how the pump is controlled. I believe it's supposed to turn on for 2 seconds to prime and then shut off until you turn the engine on. It's the stock Nikki carb and I believe its the stock fuel pump.

Do you know where the wiring diagram is at for this model? I haven't seen one.

Rotor_Venom08

iTrader: (3)

1985 Mazda RX-7 Factory Service Manual

your welcome.

have oyu checked the strainer inside the tank? and how do you "know the lines are good"? at the very least id suggest blowing them all out pretty good and seeing what comes out.

what was the cars history prior to this issue? did it run recently? was it stored for an eternity? we need more info to help you. for my money id drop the tank and take a look. also install a clear cartridge filter that you can see through. if you havent already to monitor the fuel.

these cars are very simple. ve had the same issues before ended up buying a better tank new lines and rebuilt carb, and pump. and i was off into the sunset.

nitsua93

iTrader: (2)

I thought the 1980 and 1985s would be different as far as electrics go. The reason I think the lines are probably good is the fuel pumps to the front of the car very nicely. This car was only stored for a year. All it took to get it fired up was fresh gas and starter fluid. Like I said, it has only 35K on it. Some idiot high schooler had owned it previously and did a lot of ghetto stuff to it and didn't take amazing care of it.
I'm going to pull the carb off today and clean it. Is there anything I should know ahead of time?

My main concern right now is the clicking fuel pump. It always clicks and pumps fuel when the the key is in the on position regardless of whether or not the engine is running. I'd like to fix it first, I'd rather not have to buy a $150 fuel pump if I can avid it. What would cause it to rapidly turn on/off?

diabolical1

iTrader: (3)

i was right. your pump is doing what it's supposed to be doing. relays didn't come until 1984.

Fuel Pump Relay Thread

and you are right. there are differences between S1, S2 and S3 cars as far as some of the wiring goes.

nitsua93

iTrader: (2)

I don't believe the pump is supposed to constantly cycle on and off though.

diabolical1

iTrader: (3)

maybe i'm missing something. can you post photo of the pump or video of what it's doing?
because all it is sounding like to me is that the pump is noisy and annoying you. you haven't reported any lack of performance besides the hiccup at around 3500 RPM and that could be some sort of transition issue when the secondaries are coming online.

i suppose you could unplug the pump and test the circuit both on the car's side and the pump's side, but i can't think of any on/off cycling that should be occurring.

nitsua93

iTrader: (2)

The pump clicks. When I hold the pump I can feel it surging. I really don't know how to better describe it.

I fixed the 3K rpm bog. The secondary diaphragm wasn't screwed all the way on to the carb so it couldn't hold a vacuum. Now power is inconsistent through the powerband. I will check to see if the signal is turning on and off or if the pump is somehow turning itself off regardless if it has power. I don't know why I didn't think of that. A carb rebuild is definitely in the future.

Rotor_Venom08

iTrader: (3)

that website has all the factory manuals as well.

a carter fuel pump wont set you back $60, plus a regulator. and gauge. if you want to get technical.

1980 Mazda RX-7 Factory Service Manual

ive only driven SB's no SA's s im not to familiar.

rotame12a

Would be fairly easy to just swap out the pump with a cheap electric pump for trouble shooting reasons. Those standard pumps are extremely small as well, when I bought my series 2 it was being used to fill a surge tank as the car was running a 12AT, I pulled it off and replaced it. While it was out I tested it to see how much water it would pump through, it was pathetic!

Garyrotor79

It would be good to see if it's pumping about 1.1 L per minute. It should also have about 3.7 to 4.7 lbs pressure. If it can keep up that flow your lines and filter are probably clear.
My pump runs all the time .

Garyrotor79

If you disconnect the fuel delivery line on the firewall just run tubing into a container on the floor. Let it run for a couple of minutes to get an accurate measure.