Edl 1901 Q-Jet question
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Edl 1901 Q-Jet question
Rainy day on the East Coast so I thought I'd tweak the Q-Jet. 69 427/390 with stock aluminun manifold. Carb was originally set up by Lars with a 73/42 combo. I currently have a 75/43 jet and rod combo and finally have idle mixture screw authority. Car runs pretty good with this combo and spark plugs are showing signs of tan color. While looking down the primary venturies when the car is idling at 800 rpm I see gas getting sucked down the left venturi while the right side is dry. Idle quality is a little rough but not too bad. Any idea why the left side shows fuel and the right side none?
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From: At my Bar drinking and wrenching in Lafayette Colorado
If you're seeing fuel dribbling out of the main discharge nozzle at idle, that is a problem. There should not be any fuel visible trickling out of that nozzle at idle.
2 possiblities: High float level, or throttle blade angle too far open. If I set the float level for you, it's probably pretty close to .420", but you might want to check it. Also, check how far down the power piston goes when you push it down: The inner brass sleeve should be about .020" above the top lip of the plastic retaining collar when fully seated. If the piston goes too dwwp, you often have to crank the idle speed screw in so far that the car starts pulling fuel from the main discharge nozzles.
Lars
2 possiblities: High float level, or throttle blade angle too far open. If I set the float level for you, it's probably pretty close to .420", but you might want to check it. Also, check how far down the power piston goes when you push it down: The inner brass sleeve should be about .020" above the top lip of the plastic retaining collar when fully seated. If the piston goes too dwwp, you often have to crank the idle speed screw in so far that the car starts pulling fuel from the main discharge nozzles.
Lars
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Thanks Lars. I think the float is OK but I'll double check. I'm not sure what you mean about the power piston measurement though. After reading your post again I understand. If the piston is too deep in the hole I need to adjust it higher. I have your paper on power piston adjustment.Thanks.
Last edited by 69monzaredbigblock; Nov 12, 2006 at 08:01 PM.
