BurritoBut

Right, so if you have seen one of my threads before you probably have seen me trouble shoot 34 billion things to try get my silly FC started.

Now that I have finished uni for the year, its time to get back into it.

So, I seem to be having problems with what I have narrowed down to be the fuel pump.

I can get it firing with starter fluid but it won't catch. I checked the fuel lines as I have removed emissions and they have been rerouted as per instructions.

I'll double check tomorrow but the 3B pin on the ecu gets 12v at start (which IIRC tells the car to add fuel).

To test the fuel pump I have jumped the yellow connector which should start it when the key is on. With this I have had mixed results, sometimes not being able to hear it - again I will have to have a better look at it tomorrow. I pulled the return off the fuel line and with about 6 seconds of cranking there was only about a table spoon of gas in there. Before I fixed various other issues (the 3b pin not getting power and switching the starter out) this would have had a constant flow of petrol (didn't fire due to a friend switching the leads order >_<)

Is it possible that the fuel pump has just ****ed itself? Or am I missing something.

Hopefully my ramblings make sense.

rx7_FREAKKK

iTrader: (1)

My fuel pump always comes on when i turn the key on in my 88 gxl. Try hitting it with a rubber hammer. Not to hard. should spin up. somtimes they are sticky. Also check the EGI head fuse or EJI i forgot what its called

BurritoBut

Cheers,
Yea the fuses are all good (never hurts to double check). The car has been sitting for a year and a bit now, but it was running perfect not so long ago >_<.

dwb87

iTrader: (22)

I noticed in your profile that you have a series 4 car. Is it N/A or turbo?

Are you sure that you didn't accidentally switch/mix up the fuel lines? Do you have access to an extra fuel pump to test in your car??

satch

iTrader: (1)

If everything was good the fuel should pour out of the return line so maybe there is something blocking the fuel within the fuel rails perhaps so remove the feed (send) line to the engine and check fuel at that point.

jerd_hambone

Well, usually if your pump isn't turning on all the time, that'd be the first place to check. Have you done the re-wire for the pump?

BurritoBut

Cool, thanks for the info.

Its a 1987 S4 turbo. I have the fuel lines as per the emissions removal guide, fuel filter to primary rail then secondary to return.

Unfortunately I don't have a spare on me. I'll check flow from the filter and that will tell me if its between there and the pump or in the rails.

I havent rewired the pump yet.
Is it possible the tank sucked some dirt up or something and blocked the line?

satch

iTrader: (1)

The pump has a fuel sock on it to prevent debris other than fuel to get pulled into the fuel system so yes, it is possible it could be clogged.

RotaryEvolution

iTrader: (30)

just pull the pump out and inspect it, takes about 5 minutes. you can also visually see what kind of crap has accumulated in the tank over the years while it's out.

BurritoBut

Interesting, its flowing like a **** through the filter. When I pulled the line off there was a lot of pressure. There must be a block somewhere in the rail. Its possible that I stupidly left a piece of plastic shopping bag in there from when I was masking and painting. Ill now pull the top off and start inspecting.

Is there any injector seal that may have caused this? IIRC there isn't one in the actual rail except for the o-ring on the top of the injector (which I replaced) and would be unlikely to pop off.

BurritoBut

Ahh haa!

Found the issue...

This thing (pulsation damper?) on the end is completely blocking the flow.


What should I do?

Researching niow...

jerd_hambone

Pulsation damper removal mod. Is in the archives, I'm sure.

RotaryEvolution

iTrader: (30)

uhh, that's not a pulsation dampener. someone put a second fuel pressure regulator on your inlet pipe... it's trying to push fuel through that pressure regulator backwards, which will allow a tiny bit of fuel to flow, about a tablespoon every few seconds as you said earlier.

satch

iTrader: (1)

Plus he says he has an S4 but the FPR looks more S5'ish.

rx7_FREAKKK

iTrader: (1)

did the car ever run? thats strange. never saw that before, is that an s4 fuel rail? My s4 rail does not look like that

RotaryEvolution

iTrader: (30)

it's a series 4 non turbo primary rail with a series 4 turbo fuel pressure regulator, located on the inlet where the pulsation dampener should be.

all series 5 FPRs were moulded to the stamped steel rails.

BurritoBut

Well **** no wonder its not starting...

I had a few fuel rails when I stripped it down and must have swapped it with another one because it was running fine before I took it off the road. I didn't even notice >_<.

So should I just remove it and do the banjo bolt mod or will I need to get a turbo rail?

dwb87

iTrader: (22)

Doesn't your secondary rail have a fuel pressure regulator on it?

The banjo bolt modification is for the pulsation dampener... Not for the FPR.

RotaryEvolution

iTrader: (30)

pull out your proper turbo primary rail and swap it if it is a turbo car.

in either case it's up to the condition of the part, i wouldn't junk the dampener if it's relatively new. if it's old and the screw is loose, order the banjo bolt.

i'm assuming it now has 2 FPRs, one on each rail otherwise there would be no return outlet on the secondary rail if the FPR was switched in position with the PD.

BurritoBut

I sold off the original one I think . Whats the difference?


Looks like the FPR and the PD have been switched over, here is the secondary rail...

jerd_hambone

I need to learn to look at pictures instead of just reading the text hahaha

RotaryEvolution

iTrader: (30)

the turbo rail has a more stout casting and larger diameter bore. you can run the n/a rail but the turbo rail is more ideal.

yep, just swap the FPR and the PD positions, should cure your issues.

on second thought that could well be a turbo rail, sorry i'm not at my shop there was 2 versions of the n/a rail and 1 of the TII. the n/a rail had a ski slope on it and the turbo had a rib on it, as far as i can remember now after thinking more about it.

BurritoBut

Oh ok, my spare parts motor was a turbo so hopefully these rails are from it.

The PD goes on fine but the FPR doesnt look right. Should the return nipple be in the grove?




Here is the primary - Now with new PD!



ALSO AN IMPORTANT QUESTION - Should I be able to blow air through the FPR? At the moment I can't at all

RotaryEvolution

iTrader: (30)

i can't really think of why that second locator block is there as i don't have any references in front of me. it should work the way you have it though.

BurritoBut

Sweet as, and should I be able to blow air through it or I guess it would require the pressure of the fuel pump to open it.