Fuel pump died?

[TallTim]

hello all,

I think my fuel pump may have died. I have a Duratec 2.3 with what appears to be the standard Caterham in tank pump (part no 36T004A) 

i have 12v across the outer pins on the pump connector (think the inner two are the sender), but no whining pump noise and the car won’t start.

The ground pin on the pump appears a little tarnished and the corresponding pin in the connector appears blackened 

the pump measures as 0.6ohms across its pins on the connector, meaning a 24A draw if connected but the battery voltage doesn’t dip or even flicker when the fuel pump circuit is energised. I’ve put a clamp meter on the power cable and it’s drawing no current.

im thinking the connector pin is knackered and not making a circuit

Any thoughts would be most welcome?

hopefully this link to photos will work

thanks

Tim

 

[Jonathan Kay]

What colours are all the wires?

Have you already got a wiring diagram?

Jonathan

[TallTim]

Hi jonathan,

From right to left in the photo:

yellow/green (with 12V on it)

Green (possibly Green / black) Sender out

Black (Thin gauge) Sender Ground 

Black (Thicker gauge) connected to ground

The sender wires have 34Ohms across them

I have the wiring diagram in the r400 manual, understand the colour codes, but i dont get the wire numbers next to them.

Thanks

[Jonathan Kay]

If it's the same as the diagram I'm looking at:
YG is the feed from the inertia switch.
GB goes to the fuel gauge.

In that style of diagram the numbers identify the way so you should be able to find the same number and colour code at the other end of the wire, possibly YG 168 and GB 148.

Jonathan

[TallTim]

Thanks, Thats kind of what i expected it to be... but the diagrams i am looking at dont quite work out as i would expect.

I think i am trying to marry up the R400 chassis loom drawing with the "main wiring harness for all standard instrumentation, Ford Sigma Variants", which is why the numbers dont quite work out (colour codes appear applicable to both).

The fact that i have a car that is neither an r400 or a sigma, doesnt really help... its a bit of a hybrid that someone else has pieced together, which makes this kind of faultfinding fun.

On the plus side, unplugging and replugging the fuel pump connection for the 30th time, appears to have fixed the fault and the pump now runs! 

I think i need a replacement small loom that goes from the clear square connector on the chassis loom to the inline black fuel pump connector

[TallTim]

https://caterhamparts.co.uk/looms/4586-sub-loom-fuel-pump-sigma-r400-c400.html

Looks like the ticket... thanks for your help Jonathan

[Jonathan Kay]

Edited: Crossed post.

I think i need a replacement small loom that goes from the clear square connector on the chassis loom to the inline black fuel pump connector

You might be able to buy that subloom. But changing the connector at the pump end might be all you need. I don't know what it is is but we have some experts...

colour codes appear applicable to both

Yes, Caterham generally stick to the British "standard".

Jonathan

[John Vine]

Hmmm...

The "burnt" female terminal (second from top in your photo) is the pump earth (B10 below):

It looks as though there's been some arcing, possibly due to a bent male pin or ill-fitting connector.  The black connector block is a Ford item but the CC subloom you mention already has it wired in.  I think a replacement subloom will solve your problem, but I suggest you clean and realign the male pin on the pump housing first.

JV

[bjw]

This looks like the one:-

Available on eBay:-

https://www.ebay.co.uk/itm/Connector-WPT-1091-1U2Z-14S411-AY-for-Ford-Mazda-Fuel-Pump-Mass-Air-Flow-Meter-/151760740881

Cheers

 

[TallTim]

Thanks JV,

I’ll have a good go at cleaning up the pin before fitting the new loom.

Good find on the connector, thanks. I want a few other bits so will probably go with the pre made loom this time.