Failing fuel pump?

[yetterben]

My car is running lean mid-upper range. I picked up a clear fuel filter to see if there was good flow. Well if i crack the throttle the filter runs dry and it leans out. Assuming pump is failing it is a mechanical and it is old how old who knows. If i pinch the feed line from tank for a few seconds the pump builds pressure and when i release the filter fills half way. Sound like a bad pump or maybe clogged pickup? doubt pickup as the gas is clean as can be and this just happened in the last few days.

[Z train]

Clearness of the fuel means nothing.It still could be clogged.Drop the tank and douche it out real good.If the problem persists,then do the pump.

[Walter Moore]

Are you talking about the mechanical pump I hope?

I don't remember, do Zs have a screen on the pickup in the tank?

Back "in the day" as my kids say, when we suspected a clogged fuel pickup we used to blow compressed air through the fuel line back to the tank. (If you try this, be sure to remove the gas cap, and be prepared for a big burst of gas to belch out onto the floor...) The problem with this method is that it will blow the fuel strainer off of the pickup in the tank if one is present.

Do not try this if you have an electric pump back by the tank.

Speaking of which, didn't the 73 have an auxiliary electric pump? Could the problem by that that pump is bad and the mechanical pump is having to pull fuel through a broken electric pump? Check back by the tank, under the car behind the right rear wheel. There may be an electric pump back there that is causing your problem.

[yetterben]

Nope no pump back there only two lines coming from tank and they both head straight over the diff up to the front. I will run the car from a gas can to eliminate tank theory but i am thinking pump.

I am 99.95 percent sure there is no screen on any 240. I looked whre you told me and there is no pump just the lines going over the diff. Unless its up there in the trans tunnel.

Edited June 1, 2009 by yetterben