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Shaking Engine Upon Cold Start

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Old 12-07-2007, 02:28 PM
  #1  
carlt66
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Default Shaking Engine Upon Cold Start

1966-289-c4 - with the cold weather upon me - live in Exeter RI - getting those 20 degree nights - car is garaged - not heated - having trouble getting the engine to give a smooth transitition from initial start to warmup - had no problemin the fall - I am starting the car twice a day and will drive itproviding weather is not wet - I made the mistake of letting it sit for a few days and had a real shakey engine - it shaked so bad it loosened thethermostat connectionfrom the radiator to the thermostat -I was able to stem the tide by tightening the housing -with starting the car twice a day, the shaking is not quite as bad but still there - once the engine is warm it purrs away - I also am getting the black soot as others have mentioned out of the tail pipe - the car was ovberhauled this summer - all carb adjustments were done then - the only adjustment I had to make was with the fast idle adjustment - it kept sticking open- how do I stop the shakes?
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Old 12-07-2007, 02:49 PM
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jlg2002
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Default RE: Shaking Engine Upon Cold Start

"the car was ovberhauled this summer - all carb adjustments were done then - the only adjustment I had to make was with the fast idle adjustment - it kept sticking open- how do I stop the shakes?"

First,
What does the fast idle sticking mean?

When the choke element is cold, it (should) springs the choke plate full closed prior to start when the throttle is initially opened. As the engine speed builds during cranking, a vacum based choke pull-off opens the choke plate slightly so the engine can breathe, the engine startsand the fast idle cam sets the throttle butterfly angle open to a maximum speed. As you can see, any of these will cause the problem you've described.
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Old 12-07-2007, 03:08 PM
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JMD
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Default RE: Shaking Engine Upon Cold Start

While what I am going to say might not be considered "normal", I can say that by reaching back in the recesses of my memory, I will have to convey my childhood experience that most carburated cars of the 60s and 70s seemed to run rough and shake a lot when they were started cold. I can say this even though I grew up in Arizona.

I am sure that a car in more perfect tune would not be so prone to experience this behavior, my memory says that few cars were in tuned that perfectly...

IMO, save the cold starts for when you actually want to drive the car, save the unnecessary wear and tear that cold starts certainly cause. Get a cheap 2 amp battery charger to Kerp the battery up.
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