Are there any issues with dual action fuel pumps. I have one that sucks vacuum but does push fuel ( no response on the gauge ) Pulled the pump apart and it is like new inside, fresh diaphragms, new springs and very clean. I bought this pump some time ago and been in storage.
I do have a new pump on order with MAC's.

Thanks,
Rich

Richard,

You could just have worn pump valves? Is there a fuel filter on the fuel tank side of the pump? or have you check the fuel tank pick up for blockage?

I'd blow through the fuel line you should be able to hear bubbleing in the tank.

Often the little things.

cheers

Warren

Grizzly (Aussie Mainline)

Thanks for the reply.
Yes there is a filter before the pump. The line seems clear, I can blow air through and hear bubbles. During the rebuild I dropped and cleaned the tank. I suspect the little valves, not sure how you check em.

the rubber in the valves goes hard after a while. you could start the engine with a line disconected running into some kind of container. I have to give you the warning about raw fuel pouring into the engine bay. get some help, your assistant can start the car. pretty much start stop. you should get a resonable pulse of fuel every second revolution.

Grizzly (Aussie Mainline)

My pump sat unused for a very long time and didn't move any fuel at first either. I took the base off and found that the little check valves were stuck on their seats. A gentle push against the spring tension with a screwdriver freed the valves and returned the pump to service. If they aren't moving freely, the pump won't work. Any air leaks between the pump and the fuel will also prevent it from pumping.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

I might worry more that the old rubber is not compatable with the new fuels. The more alcohol in the new fuel will raise hell with that old diaphrams.I think? Gerry

Lake Forest California  5th inf 77 Armor Div. VN 68/69

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help might be closer than you think.

Thanks again everyone. The pump from MAC claims it is made to handle the new fuels so that may be the best bet. In the mean time I will play around with the small valves. Richard

Thats one reason to stay away from NOS and older rebuilt units as the rubber parts were not meant to handle the stuff in the gas these days.If you go on Ebay there are a ton of old fuel pumps listed.If you aren't aware of the additives in the new gas you would think those old pumps were a good deal.