cold start and rough idle
Thread Starter
|
New User
Joined: Jan 2003
Posts: 10
Likes: 0
cold start and rough idle
i have an 81 f-250, just replaced the carb. when i start the truck cold it starts to sputter as i push the gas. i have to push the gas slow until it starts to sputter then let off and do it again. i have to do this a few times then it runs fine until im at a stop, then it idles very rough. any ideas what might be a cause of this?
New User
Joined: Mar 2003
Posts: 2
Likes: 0
cold start and rough idle
I'm having a similiar problem. I have a 1982 F150 4x4 with a 351W. It will turn over for a couple of minutes then quit. When you try again, it will not start. I replaced the fuel pump and I have lots of gas. There is a blue spark. I replaced the carburator with a used one from the junk yard over a month ago. It was starting and running good up to a week ago. We checked the timing and it appears to be ok. This has really stumped us. Does anyone have any suggestions for me.
Jo
Jo
Moderator
Joined: Jan 2001
Posts: 56,980
Likes: 2,735
From: Virginia
cold start and rough idle
Like the other poster said, check the choke. On a morning after it has set overnight, pull the aircleaner off. Take your hand and push the throttle wide open(don't start the truck yet), and let go. The choke flapper in the top of the carb should slam shut. Now go start it, and it should fast idle, and go back out and look, and the choke should have a small crack showing. Let it run for a minute or two, and then goose the throttle. The choke should open a little more, and the idle should drop a little. If the choke is staying shut, or is wide open, it's broke. 9 times out of 10 for me it's been the heater element in the round black choke housing. And they are expensive.
Also if you want to make the choke open faster or slower, you can loosen the screws on the round black choke housing(if it hasn't been rebuilt, it may have rivets), and turn it richer or leaner to adjust the choke.
If you look at the diagram below, they call the black thing you adjust a "thermostatic spring housing"
Also if you want to make the choke open faster or slower, you can loosen the screws on the round black choke housing(if it hasn't been rebuilt, it may have rivets), and turn it richer or leaner to adjust the choke.
If you look at the diagram below, they call the black thing you adjust a "thermostatic spring housing"
Last edited by Franklin2; Mar 24, 2003 at 06:13 PM.
