Cold Start 390

My 390 in my Cyclone starts cold, especially in winter in garage where I do from time to time. When it rumbles over, it seems a bit out of balance, even shudders a bit, for a few seconds before it smoothens out, at this time I do not give any gas but let it come up to RPM by itself. After it heats up to say 120-140 it is smooth running. Is this normal for a FE? Do I have crank balance issues; it runs fine and smooth and powerfully out on the road. Had not noticed it much before this winter as I did not have it in the garage and be starting it every week or so.

 

Blue, that's pretty much the nature of the beast. You got a whole lot of metal to heat up there. Think about how long the intake runners are on a FE engine. On a cold start you basicaly are dumping raw gas into the manifold, that gas really hasn't got any help vaporising so it sticks to the inside of the cold runners and then hits the cylinders in uneven drops. Since the drops of gas are scattered so randomly some cylinders get too much while others get starved. Once the intake manifold get's some heat in it everything evens out and your beast runs smooth. As far as starting it up periodically, you need to let it run untill it builds enough heat to open the thermostat (top radiator hose hot) so as to boil off any moisture that has condensed inside the engine. Some of that raw fuel from the cold start will have snuck past the piston rings down into the oil so heating the engine up to operating temp. has the benefit of boiling off that contaminant too. A good rule is to be ready to run that engine for about 20 minutes every time you start it.

 

Hillbilly, thanks man, I feel better, and you gave me some other good advice!! I'll listen to my Beach Boys, or old Rolling Stones CD when I start it up, give it 20 minutes! And I have garage door wide open, of course

 

Good point, thanks!! Will do. Nicer weather over here now, so I can let it "cook in" on the road more