455/Quadrajet diagnosis needed
#1
455/Quadrajet diagnosis needed
after sitting in garage for year car would not run over 4000rpm, seemed like it was running out of fuel. rebuilt but symptoms were the same. sent carb to Ruggles who now says I will not see carb for another 6 mos. bought rebuilt Quadrajet....symptoms were the same, rplaced fuel pump...symptoms are the same which are still excellent power up to 4000rpm where it just quits almost exactly like lifter pump up. spark plugs are recent and look great. I will be replacing points/coil soon, spark plug wires brand new. I am thinking crushed fuel line from gas tank and will look at that today. If all of this sounds familar or you think you know what it is just jump in here as I am just throwing parts at it now...thanx
#2
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Wow..a Rochester Quadrajet. I'm having flashbacks of my '73 Olds Cutlass. It would be a good idea to measure not only pressure but volume of fuel from the pump to see if there's a restriction somewhere. I remember there being a filter in the fuel line where it attaches to the carb but can't recall if there's another canister type in the lines somewhere else. Another place to look is at the distributor. The counter-weights under the button are rusted in place or even the points floating, though 4K rpm doesn't seem fast enough to do that..unless the spring metal holding the points is really weak.
#3
I have now just replaced the gas outlet hose from fuel pump to gas tank metal line(the old one was all cracked up with pcs of outside rubber missing, but it did not leak air when checked). I have checked and found that although the centrifigal weights and springs were operational the dist. cap to coil sockets were oxidized, that has now been cleaned up. I will check to see if there is ample dist point opening sometime the rubbing block will wear down closing up the points. I will also put another 4 gals gas in tank to make sure the little is there is not sloshing to the back under acceleration. all stops are now out...this is war!
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