Walbro Fuel Pump GSS 342 fail?

[Valve Monkey]

Hi all,

Installed a Walbro GSS 342 in tank pump around 3 months ago from and ebay seller claiming to be legit USA product. I have probably only done 3000km since.

I have spent the last day trouble shooting an very bad idle and no response from the throttle unless gradually increasing it very slowly to higher rpm. it started two days ago and became increasingly worse until undrivable, the pump was also a little noisier.

Initially I though i may have been some bad fuel from a servo that had just swapped over there tanks.
Plugged in the laptop and no warning codes and checked the amp draw on the fuel pump which was around 3.8-4A i think normal although not sounding right. Also DCM, coil packs and leads all ok. Cleaned IAC and checked air inlet. I drained some fuel to get a good sample from the return line which unfortunately was clean fuel. Checked the fuel filter and even back flushed it, lines all clear, run the pump directly into a container and it sounded normal and flowed well.

After ruling out everything else i thought I’d have a crack at installing a Fuel pressure regulator from turbosmart which i bought a while back. After much rooting around i managed to hack up the old pressure reg and tap the mounting plate to fit a 1/8 NPT to 1/4" barb and new hoses etc. Probably easier if you could find a 9/16 thread to barb fitting and tapped directly into the fuel rail.

Cranked it up to test pressure and found the gauge was barley reading a few PSI, adjusted the reg to increase pressure and could only manage 18PSI a fair way short of the 40PSI required.

1) Has anyone had trouble with these pumps?
2) Any other thoughts of what might be happening?
3) Can the Pulse Dampener fail?

I'm going to grab a new pump and install it when i have a chance in a couple of weeks.
Here are some pics of the FPR

IMAG0025s.jpgIMAG0023s.jpgIMAG0024s.jpgIMAG0026s.jpg

Apologies for the long post, any comments welcome

[Valve Monkey]

If anyone is interested I found the problem to be the pulse dampener on the discharge of the pump. It had manoeuvred itself half way round the steel fuel line bend and the pump outlet was only a few mm into the dampener. Only partial discharge remained in the fuel line and the rest back into the tank I have now fitted a small length of hose and clamps and have done away with the dampener. Someone at work said the bosch pumps pulse and its not required for the walbro. Not sure?

The walbro pump is a little shorter than the original. You could keep the pulse dampner and install a 10mm peice of hose and clamp downstream to stop any movement
Cheers!

[Valve Monkey]

Oh! the pump is a genuine Walbro GSS342 and is running fine.