AC fuel pump advice

[Lynn Eades]

Amongst us, most things have been covered. but here are a couple of other hints:
As Richard said, make sure the sight bowl seals properly or you will never get it working like it should. Sometimes the alloy is distorted.
Replace the seal around the diaphragm rod. It stops you sump filling with petrol if your diaphragm leaks. Make sure the drain hole to the outside is clear.
Some times the wear occurs at the pivot and you get lost motion. (your last picture, this is where part of the pump stays still while the other part is still moving)
What Andrew says is very important about tightening the screws. It restricts the delivery vol. (the spring dictates delivery pressure) The diaphragm must have enough material inside the pump to move freely, so activate the pump to its maximum travel and tighten the screws in this position.
I hope that helps.

[Ron Pier]

I'll have another play with the pump today. with everyone's tips and hints in mind. I have worked on these mechanical pumps before. I was a motor mechanic in the 60's and 70's when they were quite a usual fitment.

When I fit the glass bowl, I can blow and not suck to prove that the one way receiving valve is working and that the bowl in not leaking. Likewise I can suck and not blow at the delivery valve end. There's something I haven't worked out about the travel of the diaphragm......On the bench.

Cheers Ron

[Ron Pier]

Finally got my carrier running today. I fitted a new Ethanol resistant diaphragm and added about 1/8" to the pushrod. Tested the hose to the changeover valve by dumping it in a gallon can of petrol, then the pipe to the tank. I was beginning to think there was something amiss with the pickup pipe in the tank. But eventually it primed and all worked fine. Ron

[Ganmain Tony]

Hi Ron

Would you mind providing further details on the new diaphragm please?

[Richard Farrant]

Originally Posted by Ganmain Tony

Hi Ron

Would you mind providing further details on the new diaphragm please?

Hi Tony,
Not sure if you are aware but British AC pumps have different diaphragms, the spindle on British ones has two notches on the spindle and you twist them to lock in to the arm, the American ones have a slot in the end and you hook them into the arm. If you have one with a slot in, I recommend those made by MV Spares (Darcy Miller) in Sydney. Very good quality, they are for jeeps but fit other vehicles.

regards, Richard

[Ron Pier]

Yes mine is the British version. Bought from Belcher Engineering. Ron

[Ganmain Tony]

Much appreciated Richard very helpful.

Thank you also Ron. Hope that sorts out the carrier.