73 Smoking
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Joined: Feb 2009
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From: Midland TX
73 Smoking
My 1973 has been parked for about a year now, went to start it up and noticed a large amount of blueish smoke coming out the exhaust. Could this be due to oil or fuel? Or is it due to the length of time it's been parked. Any help would be appreciated! Seems to idle fine.
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Joined: Nov 2011
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MidTex,
I also have a 73 with very low miles (46000) that does the same thing. I attribute my problem to 38 year old valve seals. Not a big deal, just annoying. I presume your smoking stops after a minute or so.
Where in Mid Tex are you located?
I also have a 73 with very low miles (46000) that does the same thing. I attribute my problem to 38 year old valve seals. Not a big deal, just annoying. I presume your smoking stops after a minute or so.
Where in Mid Tex are you located?
Team Owner
Joined: Aug 2003
Posts: 24,497
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From: Scottsdale AZ
Run it more frequently, change the oil & filter and drive it a bit and that may lessen - - otherwise, it should disappear pretty quickly after start up or you'll need to look at valve seals and some head work.
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Joined: Feb 2009
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From: Midland TX
It continues after start up and warmed up for 30 minutes or so I would feel better if it stopped after a few minutes (valve guides). I live in Midland,Texas.
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From: Midland TX
Thanks everyone! Probably going to the shop with it soon, tried to blame it on the carburetor, blueish/black smoke due to also smelling fuel in the exhaust. Still has the original Quadrajet with 80k on the odometer. Older restoration.
Burning Brakes
Joined: Sep 2005
Posts: 1,050
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From: Lewes Delaware
Does it happen only at idle or also when running? My 73 with th original Qjet had the same symptoms at idle. It was running too rich so I adjusted the 2 idle screws per advice from forum members:solved the problem.
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Joined: Feb 2009
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From: Midland TX
It's happens during idle and when running. What are the recommendations for carb adjustment on the Qjets? I've heard run them in and back off 2 rounds and have also heard back them off 3 rounds. Any recommendations? Thanks!
Burning Brakes
Joined: Sep 2005
Posts: 1,050
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From: Lewes Delaware
For my idle problem, I turned them in all the way, then backed them out 1 1/2 turns. It took about 4-5 turns to back them all the way down so it was pretty far out of wack. Plus I replaced the points condenser, rotor, distributor cap and plugs and tuned/timed it according to Lars' papers.
Melting Slicks
Joined: Jul 2009
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. The guides ,springs ,ect all worn from age more than use not use. So had a machine shop , rebuilt head completely with all new parts, and had carb Q-Jet completely RESTORED , not rebuilt . All new vaccum hoses , bead blasted and painted the intake . New wires , plugs , ect . New rear main seal. The dang thing runs like dream , cranks easy, zero smoke and no oil use or leaks. Zips right up to 5500 RPM , doesn't miss a beat. 
My Corvette is needing a top end job as well, nothing has been apart ever, the carb has a kit 25 years ago put in when I bought it , it has all the simular symtoms too now. I'm gathering parts ....maybe a cam too for this motor ...well see
Last edited by LS4 PILOT; Dec 20, 2011 at 07:11 PM.
Thread Starter
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Joined: Feb 2009
Posts: 50
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From: Midland TX
For my idle problem, I turned them in all the way, then backed them out 1 1/2 turns. It took about 4-5 turns to back them all the way down so it was pretty far out of wack. Plus I replaced the points condenser, rotor, distributor cap and plugs and tuned/timed it according to Lars' papers.
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Joined: Feb 2009
Posts: 50
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From: Midland TX
my 74 Camaro 350 , is very low miles and had all these symtoms , plus it rev'd a bit slow, sluggish . The guides ,springs ,ect all worn from age more than use not use. So had a machine shop , rebuilt head completely with all new parts, and had carb Q-Jet completely RESTORED , not rebuilt . All new vaccum hoses , bead blasted and painted the intake . New wires , plugs , ect . New rear main seal. The dang thing runs like dream , cranks easy, zero smoke and no oil use or leaks. Zips right up to 5500 RPM , doesn't miss a beat.
My Corvette is needing a top end job as well, nothing has been apart ever, the carb has a kit 25 years ago put in when I bought it , it has all the simular symtoms too now. I'm gathering parts ....maybe a cam too for this motor ...well see
. The guides ,springs ,ect all worn from age more than use not use. So had a machine shop , rebuilt head completely with all new parts, and had carb Q-Jet completely RESTORED , not rebuilt . All new vaccum hoses , bead blasted and painted the intake . New wires , plugs , ect . New rear main seal. The dang thing runs like dream , cranks easy, zero smoke and no oil use or leaks. Zips right up to 5500 RPM , doesn't miss a beat. My Corvette is needing a top end job as well, nothing has been apart ever, the carb has a kit 25 years ago put in when I bought it , it has all the simular symtoms too now. I'm gathering parts ....maybe a cam too for this motor ...well see