electric fuel pump issue

[DeMinimis]

Hey folks. Sold my 79 a while back. Now getting ready to start working on my last VW, a '78 Champ Ed II. Fuel pump isn't pumping fuel. Guessing its the double relay. Seems there was a wrong way to wire the starter so that the pump turned on when the ign turned on (not waiting for the engine cranking to supply power to the pump throug the double relay). If my recall is correct on this point, how do I wire the starter to accomplish this? No need to tell me about the woes of having the pump kick in as soon as the ign is turned on. This is more of a test without going through the whole double relay testing procedure. Thanks..
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Yes Virginia, beer can make you smarter.

'78 SB CEII In Progress.

[zoti]

What are you trying to test? That the pump is working or that the double relay is suppling current to the pump?

Do you have a Bentely? It specifies how to test the double relay.
To test the pump simply connect it to an external power source.
To test the airflow flap that powers the pump while the engine is running test between the 36 and 39 terminals on the airflow connector.

If all tests well (pump working, double relay works and sends power and flap working) then test the connector to the pump on the driver side in the trunk. Follow the wires from the pump up into the trunk and you will find a connector. Wiggle it around and test again.

If someone did some wiring job on the car I would first get all the wires connected correctly.

[68IHscout]

Does the electric pump make a audible sound when working,or testing.

[DeMinimis]

This was 8.5 years ago. My hair was still mostly dark then. It was the double relay. Didn't prevent me from installing a new FP though.
_________________
Yes Virginia, beer can make you smarter.

'78 SB CEII In Progress.

[68IHscout]

[DeMinimis]

You car hear the pump when it's working. The pump won't work unless the starter is engaged (not like a buggy, for example, where you might start the pump with a dedicated on/off switch). Simply turning on the ignition will not engage the pump.
_________________
Yes Virginia, beer can make you smarter.

'78 SB CEII In Progress.

[Danwvw]

I noticed on a starter I have it's the SR-17X though the other lug than the one that goes to the key comes on during cranking only. That would be a good trigger for a fuel pump relay circuit.
I made my own fuel pump relay circuit but did not use it. Mine just comes on when the alternator light goes off. Gets it signal from the alternator light wire. The only time it is a problem is if the bus fails to start for some other reason and uses up it's fuel in the float bowls but that takes a couple of minutes so it rarely happens. I have a hidden (prime switch) to override if needed.

Looks like the 78 beetle had electronic FI and it's fuel pump is interlocked through the starter on that 50 wire terminal we are talking about and a air flow sensor.
Maybe someone put the wrong starter in it and it does not activate the relay in question? Un likely though as it's actually on the 50 wire the cranking circuit. If it cranks and does not energize then there must be a bad connection on one of the relay coils. May be cracked solder joint on the relay's circuit board. Are those relays separately housed?

Probably like it is shown here on these schematics. Note "B" (the starter) lower Left corner of the schematic and "J40" double relay (fuel pump relay) upper Right.

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[68IHscout]

I have the electrics working ,bad ground from RELAY harness to relay ,that was fixed so when cranking I do have power to the pump wires.....BUT I do have the pump out (disconnected ) and have tried to put 12 v to the pump and all I can hear is a faint click .....I am a bit confused perhaps I do have to have the pump mounted and hooked up on the car for it to work??? Thanks

[DeMinimis]

Pump should whirl when hooked up to 12v
_________________
Yes Virginia, beer can make you smarter.

'78 SB CEII In Progress.

[68IHscout]

[busdaddy]

[68IHscout]