2 replies to this topic

[kavesh]

Hi all

 

I am having issues with my quadrajet carb and trying to eliminate all possibilities.

 

I have stripped the carb several times and even had a carb rebuilder look at it.

 

Problem is initially the carb runs and idles fine. After a drive it won't idle as it should. Gets very erratic.

 

I would like to eliminate the fuel pump as a possible cause. My fuel pump is a mechanical pump and does seem to supply fuel adequately to the carb on face value.

 

If the fuel pressure is not adequate how will I know this? I do not have a fuel pressure gauge to test this.

 

I borrowed a gauge from a friend but he advised that it was designed for high fuel pressure applications and may not work. When I hooked it up, the needle did not move when the motor was idling. I hoped that it would have moved even a mm to suggest there is some pressure.

 

The pic was when the engine was idling.

 

I have an electric pump to try but really do not want to go that route.

 

Please advise.

Attached Files

•  Fuel pressure gauge.jpg   21.92K   4 downloads

[Shiney005]

Holden or Chev motor?

[arrimar]

6psi is only 0.421kg/m2 so the gauge might be fine.
You need a gauge that reads from 0 up to 15 or 20psi so the desired pressure, say 4.5 to 6psi, is recognisable on the dial.
Too much pressure the needle might not seat properly causing a stumble at idle.

Is it an AC servicable pump or a new sealed replacement?