77 Cold Natured
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
77 Cold Natured
Need some advice guys. My 77 has been cold natured when first started since the first day I owned her, and I really have not looked into trying to determine why and how to remedy the problem until now. I have always figured that my choke may not be working properly. I started checking it out last night to see if the choke butterfly was closing upon startup, and found that it was. Everytime I start the car when it is cold, I have to baby it with the throttle to keep it running until I get out of my driveway to the open road where I can throttle up. But until that point, it is all I can do to keep her running. Once the engine is warm the car idles and runs great. Any suggestions on possible causes of the problem and how to fix? Thanks in advance for your help.
Scott
Scott
Burning Brakes
Joined: Aug 2005
Posts: 1,006
Likes: 157
From: Springfield MO
I have the same problem, is yours not going to the cold fast idle?
Mine is not. Judging from the googly, this is common and the most cited "fix" is to adjust the cold idle set screw (down low on the front right). That did nothing for mine since it seems the cold fast idle is never getting "tripped".
Mine is not. Judging from the googly, this is common and the most cited "fix" is to adjust the cold idle set screw (down low on the front right). That did nothing for mine since it seems the cold fast idle is never getting "tripped".
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
No, it doesn't go into cold fast idle when I first start it. It starts, but I have to turn the engine over for a few seconds to get it to start, and then have to keep tapping and feathering the throttle to keep it running. If I don't, it won't idle and will die. It's as if the choke just isn't working. My son's 75 starts up and goes into cold fast idle just as it is supposed to, then after a few minutes you can touch the accelerator and it idles back down to normal idle speed. My 77 doesn't do any of that. I keep thinking it has to be something simple, but I am no carb expert by a long shot and have no clue how to trouble shoot.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Start by removing the air cleaner with the engine cold- before the first start of the day. Move the throttle lever one time to open, and see what the choke plate does. It should drop closed or very nearly so. Crank the engine, as soon at it starts the choke plate should open about 15* from where it was. Idle speed should be per the specs in the manual, if not, adjust as needed.
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Start by removing the air cleaner with the engine cold- before the first start of the day. Move the throttle lever one time to open, and see what the choke plate does. It should drop closed or very nearly so. Crank the engine, as soon at it starts the choke plate should open about 15* from where it was. Idle speed should be per the specs in the manual, if not, adjust as needed.
Burning Brakes
Joined: Aug 2005
Posts: 1,006
Likes: 157
From: Springfield MO
fast idle ajustment
I found this, does any of this make sense?
Fast Idle (1977-1979)
Use choke valve measuring gage J-26701. Rotate degree scale of tool until zero is opposite pointer. With choke completely closed place magnet squarely on top of choke valve. Rotate bubble until it is centered. Rotate scale so that number of degrees specified in opposite pointer. Place cam follower on second step of cam next to high step. Close choke by pushing upward on choke coil lever. To adjust, bend tang on fast idle cam until bubble is centered. Remove gage.
Fast Idle (1977-1979)
Use choke valve measuring gage J-26701. Rotate degree scale of tool until zero is opposite pointer. With choke completely closed place magnet squarely on top of choke valve. Rotate bubble until it is centered. Rotate scale so that number of degrees specified in opposite pointer. Place cam follower on second step of cam next to high step. Close choke by pushing upward on choke coil lever. To adjust, bend tang on fast idle cam until bubble is centered. Remove gage.
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
I found this, does any of this make sense?
Fast Idle (1977-1979)
Use choke valve measuring gage J-26701. Rotate degree scale of tool until zero is opposite pointer. With choke completely closed place magnet squarely on top of choke valve. Rotate bubble until it is centered. Rotate scale so that number of degrees specified in opposite pointer. Place cam follower on second step of cam next to high step. Close choke by pushing upward on choke coil lever. To adjust, bend tang on fast idle cam until bubble is centered. Remove gage.
Fast Idle (1977-1979)
Use choke valve measuring gage J-26701. Rotate degree scale of tool until zero is opposite pointer. With choke completely closed place magnet squarely on top of choke valve. Rotate bubble until it is centered. Rotate scale so that number of degrees specified in opposite pointer. Place cam follower on second step of cam next to high step. Close choke by pushing upward on choke coil lever. To adjust, bend tang on fast idle cam until bubble is centered. Remove gage.
I am sure it makes sense to someone who knows what they are doing, but it definitely is over my head.
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