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BN7 New SU Fuel Pump Fitted

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Dace

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Having fitted a replacement electronic points SU fuel Pump, I rechecked the electrical and fuel connections, put some fuel in the new ally fuel tank, turned the key - result one click from the fuel pump - nothing else? This repeats each time I turn the key (I'm just checking the pump for delivery at this point and not going for an engine start via the push button)

I expected the pump to continue "ticking" and to self prime.The pump is mounted to the vertical baulkhead, close to the originals position, the power lead is to the terminal on the cap, and an earth connection to the tag where the cylindrical body joins the base.

In my early trouble-shooting I disconnected the earth lead and still had the same single click result. Suggesting the pump is grounding through the baulkhead panel mounting bolts. Is this significant - should I have the pump electrically isolated so the only earth is via the body lead?

Any suggestions?
Dace
 
Hi Dace,
Here's a photo of how mine (a BJ8) is wired up. I have since put in an electronic pump and wired it the same way. The ground wire goes to one of the pump mounting bolts on the heel board.
 

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Are you positive or negative earth? and what is the pump.

I think that you can now get a solid state pump that can work which ever polarity you are working in but when I bought mine I had to be specific, in my case it was positive earth 'cause I still have a dynamo.

I assume that you have disconnected the petrol supply to the carbs and shoved the end into a lemonade bottle and turned the ignition on. If the pump is working at all, you should start to fill the bottle.

Bob
 
Hanging head in shame.......

During subsequent investigation of my problem I discovered I had connected the 6V batteries incorrectly giving myself a negative earth, not the required positive. I checked the fuel pump i/d's on the Burlem site and confirmed it was the positive earth required for the BN7.

It worked when correctly connected.....

Thanks for the advice,
Dace
 
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