fuel pump question

I have a '61 CJ-5 rebuilt to mostly original specs. Rebuilt 134 engine, rebuilt carburetor, and a rebuilt fuel pump. A few weeks ago I took the Jeep out and didn't get far. It died, out of fuel. At that point I hadn't replaced the fuel pump. It didn't seem to be pumping fuel up to the carb, so I replaced it. Problem solved. Today I took her out, drove about 30 minutes or so and it died again. Out of fuel. Plenty in the tank it just isn't getting to the carb. I had installed an inline paper element fuel filter between the tank and the fuel pump. So I bypassed the filter and it fired up and I drove home with no issues. My question is this: Is it possible the stock fuel pump(one with a vacuum pump) isn't strong enough to draw fuel through a paper element fuel filter designed for a fuel injected car?

 

Well I asked around and this is what I was told. You should not put a fuel filter before the pump. There is always a small amount of air trapped in the filter. That air is enough to cause the pump to loose suction. So fuel filter should go after the pump. Makes sense to me.

 

Sounds logical. But I have run filters ahead of the pump on several f-heads with no issue. Maybe it depends on te type of filter, as you suggested earlier.

 

True the transparent filters always show air (or gas vapor) in them - but they work for me. Perhaps the key is to have the outlet towards the pump low so that the pump is drawing liquid fuel from below the bubble. ???

The glass dome on the old pumps seems to function that way.

 

I acquired a fresh rebuilt 1964, CJ5 that did the same thing. The gas cap was not vented. Replaced with original type vented gas cap Also, There was no fuel filter in line so I added one after it quit and I found dirt in the carb. Since then no more problems in about 700 miles. Because I do not drive it very often I am thinking of installing an electric fuel pump to get gas to the carb quickly. Been pouring gas in the carb to get started-somewhat of pain.

 

Sounds like a vapor lock to me.. I had issues with my 75 and finally installed a fuel pump in the gas tank.. Just like water the boiling point of gas falls as the pressure decreases.. The pump in the tank raises the pressure in the line and thus the boiling point of gas in the line.

 

The optional F-134 fuel filter was intended to be mounted direct onto the Carter YF.
That said the filter location normally will not adversely effect the fuel supply.

The fuel supply is frequently interrupted by particulate matter (dirt) entering the flat end of the pick up tube.
Remove fuel flex line at fuel pump. Remove tank cap.
Inset air hose or blow back into the removed fuel line in order to dislodge the debris from the tank pick-up.
You should be able to hear the gasoline bubble violently when the fuel supply tube is cleared.