Starting problems
Thread Starter
Melting Slicks
Joined: Jan 2010
Posts: 2,416
Likes: 8
From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
NCM Sinkhole Donor
Starting problems
Since I got the car in January I have to crank the engine about 4 or 5 times before it will start. I thought it was just the cold weather,but its 80+ degrees now and its still happening. Its a 72 350 with the original Q jet (rebuilt at some time) Any ideas what may be going on? Does the carb need adjusting, or is it just 38 years old and I should be happy it starts at all? Once it starts it runs great and if the engine is hot it will start right up first shot. Any help would be greatly appreciated! 
Drifting
Joined: Dec 2009
Posts: 1,349
Likes: 34
From: Porterville Ca
Cranky
Remove air cleaner, hold choke open and check for fuel squirting into a non-running engine after letting it sit overnight. If there is no fuel, the plugs on the bottom of the carb are probably leaking fuel out of the float bowl overnight. Remove carb and turn over, find the two silver plugs that are probably discolored due to fuel leakage. Clean them up with brakecleaner, epoxy with JB weld overnight, should be good as gold after you reinstall and recheck it. 
Le Mans Master
Joined: Aug 2006
Posts: 7,417
Likes: 1,554
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Easy and free things to check!
#1 Make sure the choke is properly adjusted.
#2 After running the motor wait 5 minutes and open the 5/8 inch fuel line going into the carb. If the check valve in the fuel pump is good you should still have some pressure.
#2 After running the motor wait 5 minutes and open the 5/8 inch fuel line going into the carb. If the check valve in the fuel pump is good you should still have some pressure.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Choke probably needs a little attention. Carb may have been rebuilt many times over 38 years, but that doesn't mean it was done right.
Check it first thing in the am before starting, remove the air cleaner cover, see where the choke blade is. Push the throttle open about half way and see if the choke blade closes. It should start like that. If the choke is still open it needs some work. This is a rough check, but will tell you some of whats going on.
Check it first thing in the am before starting, remove the air cleaner cover, see where the choke blade is. Push the throttle open about half way and see if the choke blade closes. It should start like that. If the choke is still open it needs some work. This is a rough check, but will tell you some of whats going on.
Le Mans Master
Joined: Aug 2006
Posts: 7,417
Likes: 1,554
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Thread Starter
Melting Slicks
Joined: Jan 2010
Posts: 2,416
Likes: 8
From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
NCM Sinkhole Donor
Thanks for all the replies! I havent gotten back into the garage to try anything out yet. Hopefully one night this week. Thanks again!
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Le Mans Master
Joined: Aug 2006
Posts: 7,417
Likes: 1,554
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
You might want to contact Lars ( v8fastcars@msn.com ) and ask for his paper on
"Q-Jet Hard Starting and Fuel Drain-Back".