I see three sr-20’s on a daily basis. It’s torture. I also see them flying all the time, with seemingly no problems. However I live in California, so this whole starting issue I keep reading about is very distant, vague, and hard for a simple brain like mine to grasp. You mean it actually can get colder outside than 50 degrees?
So could someone please explain to me what exactly is going on in this fine engine that makes it so hard to cold start, and why such a long prime? Is it that fuel isn’t getting delivered to the right place? Does it happen on the 550 as well. Paul’s PIREP seemed to suggest it does. So is it the engine or something about the way the engine is tuned or… Please help this simple caveman 
I see three sr-20’s on a daily basis. It’s torture. I also see them flying all the time, with seemingly no problems. However I live in California, so this whole starting issue I keep reading about is very distant, vague, and hard for a simple brain like mine to grasp. You mean it actually can get colder outside than 50 degrees?
So could someone please explain to me what exactly is going on in this fine engine that makes it so hard to cold start, and why such a long prime? Is it that fuel isn’t getting delivered to the right place? Does it happen on the 550 as well. Paul’s PIREP seemed to suggest it does. So is it the engine or something about the way the engine is tuned or… Please help this simple caveman 
Good question Dean:
This is what I have been asking in a different way for the last week and hope to have more scientific answers. This “fine engine”, it seems, has some very quirky aspects to it that make it easier to start in hot weather but make it a bear to start in cold weather. By cold we mean less tha 40F. Still looking for the right answer. But when I turn the key in my car each day it starts right up immediately. Would love to see that in the Cirrus as well.
Brian
So could someone please explain to me what exactly is going on in this fine engine that makes it so hard to cold start
The problem is that Continental have restricted the flow rate of the priming pump so that if you turn the prime pump on when the engine is running it will not kill the engine (unlike older engines that suffer rich cut when you do that).
While I’m not sure why the fuel pours out the overflow, the fact is that not a lot of it is getting to the engine. It needs a rich mixture to start, and the lack of fuel is the reason you have to have the throttle almost closed (less air, same fuel, richer mixture). The long prime just gets a little more fuel into the manifold.
Electronic spark!!! Makes a huge difference.
We still have 1930’s mags.
Someday we will have electric oil pump for use prior to starting, this will eliminate pre-heaters, will make our engines last much longer, and then we will be bleased with electronic ignition. Have a great day.
Woor
I see three sr-20’s on a daily basis. It’s torture. I also see them flying all the time, with seemingly no problems. However I live in California, so this whole starting issue I keep reading about is very distant, vague, and hard for a simple brain like mine to grasp. You mean it actually can get colder outside than 50 degrees?
So could someone please explain to me what exactly is going on in this fine engine that makes it so hard to cold start, and why such a long prime? Is it that fuel isn’t getting delivered to the right place? Does it happen on the 550 as well. Paul’s PIREP seemed to suggest it does. So is it the engine or something about the way the engine is tuned or… Please help this simple caveman
Good question Dean:
This is what I have been asking in a different way for the last week and hope to have more scientific answers. This “fine engine”, it seems, has some very quirky aspects to it that make it easier to start in hot weather but make it a bear to start in cold weather. By cold we mean less tha 40F. Still looking for the right answer. But when I turn the key in my car each day it starts right up immediately. Would love to see that in the Cirrus as well.
Brian
What is it about the Cirrus specifically that makes this so hard? Why do I read about pilots watching horrified as Cessnas and Pipers fire right up as they sit there in prayer at the prime switch?
Thanks, Clyde. Interesting and what I suspected… In a fear of one condition (in-flight failure) they’ve used a design that naturally suffers on the opposite end of the specturm (cold start)
On a perhaps related note, the FAA is considering a sweeping AD on all new Cessna singles for the in-flight problem of too-rich mixtures causing a rash of engine failures.
Just think, one day, maybe soon, all these problems will seem ridiculously archaic. What, humans did the mixture? How crude and inefficent.
Dean
Amen to that. I had a really tough start last night in MRY for the final leg of the ferry flight home. Turned out I had put the throttle at my customary 1/4" spot (Cherokee). I primed and primed and primed and primed w/no Joy. Brought the throttle almost totally closed (2mm?) and it started like a charm.
The fuel air mixture on start is very touchy on my 550.
Paul
Just think, one day, maybe soon, all these problems will seem ridiculously archaic. What, humans did the mixture? How crude and inefficent.
Dean
Are you implying that they don’t already seem ridiculously archaic?
Tom