extreme cold no start and run

[wobbedennis]

My Datsun 210 is my daily driver, and she has been a good one. but the other morning, she wouldn't start, and run. she would try to run, but not for long, and when I finally got her to run, she wouldn't idle, at all, had to keep the rpms up to about 2000 to keep her running, and I needed to unchain her to drive her in. it was 3 below zero that morning and I had to drive my Ford truck in. I can't afford to drive that truck every day. suggestions on helping the car start and run in the cold we've been having here would be of great help.

[racerx]

maybe your choke is not working right.  Not sure about 210 if it's a manual or auto choke.

[wobbedennis]

it has an optional electric choke, and it does work. verified that aready

[MikeRL411]

Icing carb?

[datzenmike]

Check when cold... take air filter off. Look in and pump the gas by hand. The choke plate should snap shut! Harder to see at the back is the fast idle cam. When the choke closes the fast idle cam should drop down, and when you release the throttle it will sit against this cam and be held open. Sorry I don't have a picture of a 210 carb.

 

This is the L series Hitachi fast idle cam. When the throttle is opened on a cold motor, the choke plate snaps closed and a linkage allows the fast idle cam to drop down and when the throttle is released it closes on the cam steps. If you look at the bottom you can see steps like a staircase.

 

Here you can see the fast idol set screw has closed on the second step and is being held open allowing more air in and a faster idle.

 

 

Once the motor warms the choke plate open, a linkage lifts the fast idle cam up and out of the way and the throttle can close fully to it's normal idle condition.

 

Find the fast idle cam and be sure it is clean and free to drop into position. It can easily get stuck so liberally spray carb cleaner or WD-40 and work all the linkages to free them up. Hold the throttle part open and close and open the choke plate.... the fast idle cam should drop into position and lift back up as you do so. It should do this easily and freely.

 

Tomorrow you get in your 210 and pump the gas several times to...

1/ pump raw gas from the accelerator pump to richen up the start mixture.

2/ set the choke to ON and set the fast idle cam.

 

Crank the motor over and it should not only start but rev up to 1,800- 2,300 rpms.  This will allow you to get out and clear the windows or drive away immediately.  

[ggzilla]

Carb icing doesn't happen when you let the carb sit -- it happens while driving the car. Unless there is water in the carb, there is nothing to freeze. Carb icing causes the moisture in the atmosphere to freeze around the throttle blades, holding them open.

 

My guess is that there is water inside the carb. Once it gets above freezing, clean the fuel bowl. Do not remove the carb from the engine. See instructions

[wobbedennis]

Well, it only happens when the temp drops below 0, it was one below that morning, and the morning before was three below. just too cold. Any way, I think the jetting is worn out from it's 34 years of use, and I can't get it, so I'm gonna get a reman carb from National Carburetors.

[ggzilla]

That is not too cold for a carburetor. If it has enough choke, even a worn carb will start right up.