Fuel Delivery Problem, No Fuel to Fuel Rail (cross post) Options

[AvalonFal]

This is a cross post to multiple sites.

'74 2.0L with stock d-jet. Just installed a new (at least that's how it was advertised) original type 3 port fuel pump in the original rear location and now car won't start. Pump comes on, engine cranks very strong, but no start. There is good fuel flow to the pump, but no fuel to the passenger fuel rail. It seems that all the fuel is going to the return line back to the tank.

Any thoughts??

Paul

[Cupomeat]

Sounds like a fuel pressure regulator issue.

I guess, just to be sure, is one installed after the injector rails before the return line? I has to be the last component in the fuel path before returning to the tank.

Check your fuel path, and if all that is done, check your FP regulator.

Hope that helps.

[ericread]

Is there any chance you inadvertantly crossed the fuel lines to the three ports? Sounds like you may be pumping fuel right back into the return line...

Just a thought...

Eric

[AvalonFal]

Is there any chance you inadvertantly crossed the fuel lines to the three ports? Sounds like you may be pumping fuel right back into the return line...

Just a thought...

Eric

Pressure reg. in place where it should be.


Pump connected as:
Center port to passenger fuel rail
Port closest to relef valve to return line "Y"
Top port to larger supply line from tank
Correct?

Paul

[ericread]

Maybe this informaiton previously posted by Andy will help:

"S" is suction (from the tank), "D" is Druck or pressure to the FI system and "R" is return (pump bypass if a clog occurs in the engine lines) and is "T"ed to the line from the pressure regulator and then back to the tank.

EDIT:

Here's Dave Darlings diagram:

[AvalonFal]

Maybe this informaiton previously posted by Andy will help:

"S" is suction (from the tank), "D" is Druck or pressure to the FI system and "R" is return (pump bypass if a clog occurs in the engine lines) and is "T"ed to the line from the pressure regulator and then back to the tank.

Here's how I have the pump connected:

Paul

[orange914]

Sounds like a fuel pressure regulator issue.

if it's a faulty reg. dumping pressure, you can test it and the pump by pinching off the return line AFTER the regulator. this gives full pump pressure.

[swl]

Ok so you put a new pump in - chances are the problem is associated with that.

There is a failure mode on the 3 port pump where the bypass doesn't close and fuel does indeed just get pumped back to the tank. That should be easy to see by rigging up a collection system.

Did your replace hoses or just plug in the old ones. If you replaced hoses 'while you were in there' it is easy to get the two tubes mixed up and wind up trying to push fuel backwards through the cct.

[Dave_Darling]

My bet is that you got the hoses on the wrong fittings of the pump. Either that, or the electrical plug is in backwards...

Not that I've ever done either of those myself. More than six times.

--DD

[AvalonFal]

My bet is that you got the hoses on the wrong fittings of the pump. Either that, or the electrical plug is in backwards...

Not that I've ever done either of those myself. More than six times.

--DD

Dave:
See my pic above for the pump connections.

Center port to passenger fuel rail.
Port at relief valve to "Y" to return line to tank.
Top port (away from electrical plug) to fuel filter outlet.

Are all "original" type 3 port pumps configured the same, that is, are the ports are in the same locations? This pump has no ID markings on the 3 ports.

If the bypass is staying open, how can that be fixed??
Paul

[Dave_Darling]

No markings? Yikes, that sucks!

The R port is the one that has the silver "hat" on the side next to it. Your pic says you have that one hooked up right.

The pumps should be set up the same way, because of where the inlet/outlet are relative to the pump rotor. (Brings to mind another question: Has this pump been taken apart? If so, could have been assembled incorrectly. Did that on mine.)

The bypass is a spring-loaded valve. The spring and I think the valve are under that silver cap on the side of the housing. You may be able to take the cap off and free up a stuck valve, but I'm not sure how you get the cap to stay on again afterward.

--DD

[Cap'n Krusty]

I think you're on the right track, Dave. The Chinese pumps are reported to have significant QC issues. While I'm here, I noted in the picture a DEFINITELY substandard non-FI rated fuel filter and the lack of the stepped hose. I can follow up with the correct PN later.

The Cap'n

[AvalonFal]

OK, here's the result.

Apparently the 3 port pump sold to me from down south is an aftermarket pump. The problem with the ports not being ID'd is that the ports are DIFFERENT on this pump than the original configuration. On the original pump, the center port is the "pressure" port (to the engine) and the port at the silver cap end is the relief valve back to the return lines. NOT SO WITH THE AFTERMARKET PUMP. Those ports seemed to be reversed. The center port is the relief port and the port near the silver cap is the pressure port to the fuel rail. I switched the hose connections and the car started right up on the 1st try after sitting unstarted since before Xmas!! I left it running for a good 1/2 hour and everything seemed OK, except for a small drip at the pump (I'll have to make sure everything is tightened).

I guess that explains why all the fuel was pumping through the return line to the tank with the original connections. Who knew??? Does this sound OK to use the pump as is??

Has anybody else used these aftermarket pumps??

AA, did you know this???

Paul

[swl]

Are the ports reversed or is your plumbing reversed? I can't imagine how the pump could be built with pressure on the silver cap side.

[AvalonFal]

Are the ports reversed or is your plumbing reversed? I can't imagine how the pump could be built with pressure on the silver cap side.

I disconnected the original hose connections at the pump and put the "Y" connection to the center port and the fuel rail hose connection to the silver cap side port and the engine fired right up.

Paul

[AvalonFal]

I think you're on the right track, Dave. The Chinese pumps are reported to have significant QC issues. While I'm here, I noted in the picture a DEFINITELY substandard non-FI rated fuel filter and the lack of the stepped hose. I can follow up with the correct PN later.

The Cap'n

Cap'n:
The filter was bought from Pelican - part #311-133-511-D-M67. did they send me a bad one?? And yes, the stepped hose is temporarily missing and will be installed when I'm sure this fuel pump mess is finally resolved.

Paul