Idle too high when slowing down and assorted issues
BLyke said
May 21, 2020
My car seems want to get the choke or something else stuck much of the time when slowing down.
A tap of the gas pedal will drop it back down.
Nothing is obviously sticking, the choke opens all the way when warm.
I put a little oil on the shafts and seemed to be a bit better.
Any suggestions??
-- Edited by BLyke on Sunday 7th of June 2020 03:52:41 PM
dashboard said
May 21, 2020
Return spring? Under normal conditions what RPM is the idle at?
BLyke said
May 21, 2020
It was ~600-700 but when it "sticks" I'M thinking it it a lot higher
no tach on the car, dug out my old tach/dwell meter (after ~30-35 years?)
Bobs_Place said
May 21, 2020
Shut the car off( in a safe place) when the engine won't idle down, don't touch the throttle, pull the air cleaner and check to see if the choke is partly closed, also check the fast idle cam on the right side of the carb. Check throttle cable, to short or hanging up and on allowing the throttle to return?
Lost in the 60s said
May 21, 2020
After checking Bob's suggestions, a little carb cleaner on the choke/fast idle cam linkage will help clear any gummy substance from sitting.
How is the spring placement/tension ? Can you pull the throttle open with minimal effort ? May need to double spring it.
Jon H said
May 21, 2020
I changed the throttle return spring last year and had the same issue. I put a shorter spring on and the issue disappeared.
BLyke said
May 22, 2020
Thanks for the suggestions guys!
The cable was just replaced with a new one, and cleaned the linkage.
The spring is suspect looking, not sure it is even a original type.
May try Bobs idea to see what it is like when happening.
Hopefully it is as simple as the spring.
BLyke said
May 22, 2020
since this is apparently what it should look like.. think it is a likely fix and will try it next. the one that came with the car looks nothing like it, funny, everything else was done right by the PO
Check where the spring is attaching to the throttle place and engine also. Selecting the wrong hole on the throttle plate has a big impact on the force to close the throttle and the wrong spring angle from throttle plate to engine may let off too much spring force as the throttle closes.
BLyke said
May 22, 2020
Got the new Dorman springs for the car and it works great. Also the feel of the pedal is very solid and precise. Think I need to add to my trouble shooting list to consider if it was that way when I got the car... if it likely to be correct?
Here is what was on the car (looks a bit like a part of a screen door chain )
My car seems want to get the choke or something else stuck much of the time when slowing down.
A tap of the gas pedal will drop it back down.
Nothing is obviously sticking, the choke opens all the way when warm.
I put a little oil on the shafts and seemed to be a bit better.
Any suggestions??
-- Edited by BLyke on Sunday 7th of June 2020 03:52:41 PM
no tach on the car, dug out my old tach/dwell meter (after ~30-35 years?)
Shut the car off( in a safe place) when the engine won't idle down, don't touch the throttle, pull the air cleaner and check to see if the choke is partly closed, also check the fast idle cam on the right side of the carb. Check throttle cable, to short or hanging up and on allowing the throttle to return?
How is the spring placement/tension ? Can you pull the throttle open with minimal effort ? May need to double spring it.
The cable was just replaced with a new one, and cleaned the linkage.
The spring is suspect looking, not sure it is even a original type.
May try Bobs idea to see what it is like when happening.
Hopefully it is as simple as the spring.
since this is apparently what it should look like.. think it is a likely fix and will try it next.
the one that came with the car looks nothing like it, funny, everything else was done right by the PO
Got the new Dorman springs for the car and it works great.
Also the feel of the pedal is very solid and precise.
Think I need to add to my trouble shooting list to consider if it was that way when I got the car... if it likely to be correct?
Here is what was on the car (looks a bit like a part of a screen door chain )
Have you considered adding another spring as a safety feature? There were two springs on the chevelle I got last fall.
Yes the new ones are double and work great.
Yesterday the Fuel Pump went out, fortunately less than 2 miles from home.
After messing around with Roadside assistance... called a friend and we towed it back.
When working on the engine I noticed things on the pump were a bit odd looking.
Turns out the old pump was some sort of metric adapter on what is likely a newer unit.
It is now running fine and the adapter is gone.
Shake down continues as we are up to ~350 miles for the year.
New tires are working out great.