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Almost impossible cold start

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Old Jul 17, 2017 | 08:13 AM
  #1  
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From: Surtainville
Default Almost impossible cold start

Hello, I am the proud owner of a C3 1979 L82 engine, but since a week now I have a hard time to start the car. I changed the spark plug and the wires as well as the Delco but doesn't change much. I tried to check the timing but the mark is very unstable and at times completely out of the timing light (can't even see the mark). I need some help please. Two weeks ago the car started fine and was at 900 rpm at idle and now it is just about 600 rpm, I didn't do or touch anything in bettween.*
Thank you,
Anthony
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Old Jul 17, 2017 | 08:21 AM
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From: Meriden CT
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Take a look at the mechanical advance springs under the distributor rotor. One or both may have broken. I the distributor loose? And, what do you mean by Delco?
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Old Jul 17, 2017 | 08:56 AM
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From: Surtainville
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Thanks for your reply. Soory Delco is probably a brand name for the distributor cap (I'm in France, and I'm not even sure we call it Delco here either). I'll check the spring but when I remove the distributor cap it didn't look broken. As for the distributor being loose I'll check it right now.
Thanks again.
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Old Jul 17, 2017 | 10:58 AM
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You have to remove the distributor cap and the distributor rotor to see the springs.
Are you disconnecting the vacuum advance when you are checking the timing?
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Old Jul 17, 2017 | 01:24 PM
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From: Surtainville
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Ok, I've checked the springs and they're fine. As for the timing, how dumb can I be, I forgot to disconnect the vacuum from the advance. Now the timing mark is where it should be but the idling is too low 600 rpm (900 rpm before). I don't know what happened for it to change.
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Old Jul 17, 2017 | 02:00 PM
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Check your choke operation
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Old Jul 17, 2017 | 02:17 PM
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As stated above check the choke, does it fully close when the engine is completely cold?
Does it gradually open as the engine heats up?
With the engine off, look down the primary side of the carburetor and open the throttle by hand you should see gas on both sides squirt into the throttle bores.
On the passenger side of the carburetor there are some vacuum hoses connected to diaphragms on the choke linkage, are the hoses connected and not cracked?
Are the bolts that hold down the carburetor to the intake manifold loose? Do not over tighten them.
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Old Jul 17, 2017 | 03:12 PM
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From: Surtainville
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Thanks for your suggestions, as on my side of earth it is already past 9 pm I will check it all tomorrow morning and let you know.
Thank you for your help.
Anthony
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Old Jul 17, 2017 | 04:14 PM
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Ignition Module
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Old Jul 18, 2017 | 01:03 PM
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From: Surtainville
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OK, after removing the distributor cap and rotor to check the springs (they were fine) and clean them with WD40, the car starts no problem (just as it did before). The choke (electric) works fine. The idle speed is still low (600 rpm instead of the 900 rpm before). I just hope it will start just as good in the days coming.

By the way, what to you mean by ignition module (I have HEI ignition).

Last edited by AGG50; Jul 18, 2017 at 02:40 PM.
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