quadrajet help please......
Thread Starter
Instructor
Joined: Oct 2007
Posts: 183
Likes: 1
From: Philmont NY
quadrajet help please......
I have a 1968 327/300 HP....I went back to the original carb 2 years ago did a complete rebuild and it was fine. It sat for over a year while paint / suspension work was done. Float stuck open 1st drive out. Piece of rubber off of excelerator pump.....bought a new rebuild kit, cleaned the carb, replaced the excelerator pump...messed with float level..and air adjustment screws in front of carb....screwed it all up.
I have now set the float level back to 9/32..adjusted air screws to their highest level of vacuum (15)....and it still stumbles / sluggish. When I look at the carb while running / idleing....there is gas trickling in the right side of the carb the way it should, but not the left side. The airhorn gasket is also getting damp with gas as it runs. I was going to try and adjust the float up a hair because of no gas coming in the left side by do not think that is the problem because of the gasket getting wet.
What should I try...I thought maybe a leak, but my vacuum is good (so I think). All scews and bolts holding the air horn on are tight as can be and tightened down in the proper order.
Thanks,
Jeff
I have now set the float level back to 9/32..adjusted air screws to their highest level of vacuum (15)....and it still stumbles / sluggish. When I look at the carb while running / idleing....there is gas trickling in the right side of the carb the way it should, but not the left side. The airhorn gasket is also getting damp with gas as it runs. I was going to try and adjust the float up a hair because of no gas coming in the left side by do not think that is the problem because of the gasket getting wet.
What should I try...I thought maybe a leak, but my vacuum is good (so I think). All scews and bolts holding the air horn on are tight as can be and tightened down in the proper order.
Thanks,
Jeff
Race Director
Joined: May 2006
Posts: 18,692
Likes: 2,572
9/32=.28125 which means the float is too high, I believe the correct setting is .375. When you cleaned the carb and replaced the pump did you also check the pump check ball located under the screw in the bottom of the accelerator pump shaft?
Thread Starter
Instructor
Joined: Oct 2007
Posts: 183
Likes: 1
From: Philmont NY
I will re adjust the float...but not sure what you mean by check ball? Are you talking on the plunger itself or the base of the carb?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
If the accelerator pump seal was cut during prior assembly, the change of float level may solve your problem. If the seal failure was due to other issues, there may be other pieces of that seal which have migrated into passages/orifices in the carb body. Since you have to pull the top off the carb anyway, I would recommend that you take it completely down, replace the needle valve [as a precaution against it having taken a "set" or becoming 'hard' during the long storage], and blow through all the passages/orifices to be certain they are clear. If you damage any gaskets during your work, a new rebuild kit might be useful. That will also provide you with an exploded view of the carb parts so that you can identfy the check ball and its location.
Thread Starter
Instructor
Joined: Oct 2007
Posts: 183
Likes: 1
From: Philmont NY
I set the float level to the first setting you gave (.375)...looked for the ball...did not see anything in the well the plunger sits in? I did take out the screw next to it and everything seemed to be fine. So I put it back together and it seems to have a much better response when I hit the gas...I will take it out on the road tomorrow to see.
There is still no gas trickling from the left side of the carb...but does not seem to be an issue (right now)....should there be..I blew through the hole and it was not blocked?
There is still no gas trickling from the left side of the carb...but does not seem to be an issue (right now)....should there be..I blew through the hole and it was not blocked?
Tech Contributor
Joined: Aug 1999
Posts: 14,373
Likes: 6,371
From: At my Bar drinking and wrenching in Lafayette Colorado
There should not be any fuel visible or trickling in either venturi at idle - all idle fuel is discharged below the throttle plates. If you can see fuel discharging or dripping in the venturi, you have a problem.
All these problems are outlined in detail in the papers I have made available to Forum members for the past 5 years. All you have to do is request the papers.
Lars
V8FastCars@msn.com
All these problems are outlined in detail in the papers I have made available to Forum members for the past 5 years. All you have to do is request the papers.
Lars
V8FastCars@msn.com
Thread Starter
Instructor
Joined: Oct 2007
Posts: 183
Likes: 1
From: Philmont NY
There should not be any fuel visible or trickling in either venturi at idle - all idle fuel is discharged below the throttle plates. If you can see fuel discharging or dripping in the venturi, you have a problem.
All these problems are outlined in detail in the papers I have made available to Forum members for the past 5 years. All you have to do is request the papers.
Lars
V8FastCars@msn.com
All these problems are outlined in detail in the papers I have made available to Forum members for the past 5 years. All you have to do is request the papers.
Lars
V8FastCars@msn.com
I really appreciate you taking the time to chime in.....I will e-mail you for the papers. Once again....thanks...
Jeff
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