Re: Problems while starting the car?
Posted by HH56 On 2022/8/1 14:17:44
Quote:
The accelerator linkage works a spring loaded plunger in the carb starter switch that moves to close contacts and energize the starter solenoid. As soon as the engine starts your normal instinct is to let off the accelerator pedal. The relaxing of the linkage lets the spring push the plunger back breaking the contacts and de energizing the solenoid so the starter motor should stop. The now present engine vacuum then draws a small connecting ball between the accelerator linkage and the plunger up into a passage breaking the mechanical connection to the plunger so it can no longer be engaged by the accelerator as long as the engine is running. The ball is also pulled against a seat in the passage which blocks off any vacuum leak thru the linkage or switch.
Unless the accelerator linkage itself is sticking and not returning to the relaxed position fully, the strongest possibility since you can get the starter to stop by turning the key off is the switch contacts have arced or become pitted and is not releasing smoothly or it could have gotten hot and the spring has lost tension. Checking or cleaning will require removing the switch from the carb but when you do so take extra care to account for all pieces in the order they come out. There should be some tiny shims that need to go back in the same position and the plunger must go back with the tapered point on the end down exactly like it came out.
Here is a bit on the switch from an old Motors Manual and a factory piece from Carter that someone -- maybe Ross -- posted on the forum. Unfortunately the photo is not very clear on that one.
NOTE: I deleted the copy I had posted of the Carter factory documentation. The cleaned up version Guscha did in the next post is far superior.
Attach file:
Carb switch1.pdf Size: 285.77 KB; Hits: 60
TMoney wrote:
If I use the floor starter the starter engages like normal, but it never disengages. To get it to stop I just have to cut the car off. I hope this helps. I am very new to this car world.
The accelerator linkage works a spring loaded plunger in the carb starter switch that moves to close contacts and energize the starter solenoid. As soon as the engine starts your normal instinct is to let off the accelerator pedal. The relaxing of the linkage lets the spring push the plunger back breaking the contacts and de energizing the solenoid so the starter motor should stop. The now present engine vacuum then draws a small connecting ball between the accelerator linkage and the plunger up into a passage breaking the mechanical connection to the plunger so it can no longer be engaged by the accelerator as long as the engine is running. The ball is also pulled against a seat in the passage which blocks off any vacuum leak thru the linkage or switch.
Unless the accelerator linkage itself is sticking and not returning to the relaxed position fully, the strongest possibility since you can get the starter to stop by turning the key off is the switch contacts have arced or become pitted and is not releasing smoothly or it could have gotten hot and the spring has lost tension. Checking or cleaning will require removing the switch from the carb but when you do so take extra care to account for all pieces in the order they come out. There should be some tiny shims that need to go back in the same position and the plunger must go back with the tapered point on the end down exactly like it came out.
Here is a bit on the switch from an old Motors Manual and a factory piece from Carter that someone -- maybe Ross -- posted on the forum. Unfortunately the photo is not very clear on that one.
NOTE: I deleted the copy I had posted of the Carter factory documentation. The cleaned up version Guscha did in the next post is far superior.
Attach file:
Carb switch1.pdf Size: 285.77 KB; Hits: 60This Post was from: https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=246654