Quadrajet Accelerator pump causing stuck throttle?
May 27th, 2021, 02:29 PM
#1
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Quadrajet Accelerator pump causing stuck throttle?
I just rebuilt my carb on my 1983 Delta 88 with a kit and after buttoning it all back up together its running well but... too well. Its idling a little high and when I press the throttle it wants to stick at its highest RPMs like the spring on the pump cup is stronger than the return spring on the throttle.
When rebuilding I put the new little rubber boot on the end of the accelerator pump but everything else is original including the spring that goes on and below the pump.
Is this an issue anyone has encountered before? I'm about to take the air horn back off to investigate but should I spray some wd40 in there or clean up the bore some for less friction?
When rebuilding I put the new little rubber boot on the end of the accelerator pump but everything else is original including the spring that goes on and below the pump.
Is this an issue anyone has encountered before? I'm about to take the air horn back off to investigate but should I spray some wd40 in there or clean up the bore some for less friction?
May 27th, 2021, 02:56 PM
#2
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Join Date: Mar 2007
Location: Northern VA
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On the Qjet, the accelerator pump can't hold the throttle open - it pushes it closed. If the pump itself stuck in the bore, the pump arm would just gap at the top of the pump, it can't pull the throttle open. Your problem is elsewhere.
I did have one instance where the gasket between the main body and the float bowl was slightly undersize at the throttle bores and held the throttle plates slightly open.
I did have one instance where the gasket between the main body and the float bowl was slightly undersize at the throttle bores and held the throttle plates slightly open.
May 27th, 2021, 03:10 PM
#3
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Ah yes that is true. Must've had my thinking cap on backwards!
I did not mess with any adjustment screws during the rebuild so I now wonder whether a choke could cause the original problem at hand.
I did not mess with any adjustment screws during the rebuild so I now wonder whether a choke could cause the original problem at hand.
May 27th, 2021, 03:11 PM
#4
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May 27th, 2021, 03:31 PM
#6
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Yeah its the CCC. In terms of the TPS I just made sure it was positioned correctly but it seems you're alluding to a special process behind that.
FWIW I also found a factory service manual on eBay for 10 bucks so that should be here next week.
FWIW I also found a factory service manual on eBay for 10 bucks so that should be here next week.
May 27th, 2021, 04:00 PM
#7
Old(s) Fart
Join Date: Mar 2007
Location: Northern VA
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No, just taking the care to ensure it doesn't drop out of position when you install the air horn. Not everyone appreciates that. The bigger issue is the carb adjustment process. The CSM will provide the details.
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