Air fuel mix screw way out.
12-19-11, 07:16 PM
#1
Air fuel mix screw way out.
Hi, in order for my 7 to run right, the air/ fuel mix screw has to be turned waaay out. It also seems to lack in power a little bit. Entire fuel system has been taken care of. I don't think the cats are clogged because I blew catalyst into the muffler. fuel pressure is spot on. No apparent vacuum leaks. Any ideas?
12-19-11, 08:57 PM
#2
Mine is about 4 turns out. But that's with a removed rats nest and a pcv valve.
Seems out too far based on all the "initial settings" read here, but it was that way years ago when I bought the car in stock form, and after I went through the carb.
Is this what you mean by way out?
Seems out too far based on all the "initial settings" read here, but it was that way years ago when I bought the car in stock form, and after I went through the carb.
Is this what you mean by way out?
12-19-11, 09:22 PM
#3
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i think factory spec is like 2.5 turns? so +/- 1 turn from that is reasonable.
if its further that means its not getting enough fuel, either because of a vacuum leak, or an idle circuit that is not working.
it could also be that something else is wrong, like the ignition isn't working right, low compression, or the carb idle speed settings/linkage is wrong, but you'd have other symptoms
if its further that means its not getting enough fuel, either because of a vacuum leak, or an idle circuit that is not working.
it could also be that something else is wrong, like the ignition isn't working right, low compression, or the carb idle speed settings/linkage is wrong, but you'd have other symptoms
12-20-11, 03:01 PM
#5
I'm guessing 4 might be too far, and a possible idle circuit issue. That said, the only other symptom is throttle closed engine braking...push in clutch... and 90% of the time the carb will not catch itself and will go very lean 17-20:1 per Wideband, and stall the engine.
12-23-11, 10:08 AM
#6
Rebuild your carburetor. It's pretty easy once you have it out. Go to sterlingmetalworks.com for help on rebuilding and tuning. You could have a damaged needle valve. Hopefully nobody overtightened it and fudged the needle tip up. I would remove and gut the cat or replace it with an RB presilencer just because it's better for your performance.
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