Idle stopsolinoid LT1 (72)

[Rob Cetrone (42529)]

I think My solinoid stoped working.
It energizes but will not push the throtal forward. I have been playing with it to set my idle. I did not turn it much at all. It did get real hot but I would think that it would still operate ok.
Any help would be great. Is it fixable or do I have to start hunting. If I need a new one were do I start. It has to look just like the origanel.
Thank You.
Rob
hunter1usa@verizon.net is my E-Mail

[Patrick Hulst (16386)]

Re: Idle stopsolinoid LT1 (72)

If you're handy, they can sometimes be repairable and/or cleanable.
Else Lectric Limited now sells a reproduction, and NOS ones show up on ebay.

I usually find that mine will NOT lift the throttle up on its own, but will KEEP the throttle lever up if I tap the throttle. That's one of the unique things about owning a 72 - knowing how to "use" the solenoid. So, I always turn the key to On before I press the throttle to kick on the choke. This will also allow the solenoid to hold up the throttle lever at the correct idle position.

Hope that helps.

Patrick

[Rob Cetrone (42529)]

Re: Idle stopsolinoid LT1 (72)

That helps but if I dont let down on the throttle easy it pushes in. Does lectri limited look like the origanel?
Rob

[Patrick Hulst (16386)]

Re: Idle stopsolinoid LT1 (72)

That I don't know. You'd have to check with them.

[Jack Humphrey (17100)]

Re: Idle stopsolinoid LT1 (72)

Pat's correct, the idle stop solenoids were marginal in terms of forcing the carb's pedal linkage backwards... There were designed to fire and change position with either the car in motion or during cold start presuming you turned the ignition ON, and THEN set the choke by pressing the accelerator to the floor BEFORE turning the ignition switch to the start position.

Sounds to me like your original solenoid is working just like it's supposed to.
On does this/that guy's replacement solenoid 'look' like a factory original, generally the answer is not a snowball's chance in Hades! Replacements were available from SEVERAL independent manufacturers (e.g. Standard Motor Products), but they're not going to have the original Delco Remy identifying marks on them and may vary significantly in terms of geometry (length + diameter).

All that mattered for fit/function is the electric terminal would accept the stock wiring harness connector, the front of the solenoid would install in the carb bracket, and the front plunger had at least the same throw length & minimum holding force profile as the Delco Remy original....

[Rob Cetrone (42529)]

Re: Idle stopsolinoid LT1 (72)

OK, so when my car is up to temp and the choke is off I step on the gas pedal and I then take my foot off the gas pedal the linkage comes back and hits the plunger the plunger on the solinoid gets bumped in. I hit the pedal again to see if it resets it's self and does not unless I manualy do it.
Is my solinoid good?
Thanks for all your responses.
Rob

[Patrick Hulst (16386)]

Re: Idle stopsolinoid LT1 (72)

No, your solenoid does not appear to be functioning 100%.
But, without seeing it operate, I can't tell you if it can be repaired (Jack as well as Gary Schisler taught me how to do this) or if you need a new one.

[Jack Humphrey (17100)]

Hum, not quite....

On-board electronics control the solenoid. One logic path is engine cold, car has just started. In that case, the control relays ought to detect engine temp + start a timer and fire the solenoid to achieve fast idle for improved cold engine driveability. BTW, this 'lecture' should be in your copy of the 1972 Chassis Service Manual under the Emission Control section....

The solenoid releases when BOTH of two conditions are satisfied:

(1) The 15-40 second timer relay has expired.
(2) The engine coolant switch (RH cylinder head) detects 'normal' engine operating temp has been achieved.

From that point on, the solenoid is controlled either by the transmission or the engine coolant switch. When the car is in 'high gear(s)' (makes a difference whether we're talking AT or MT transmission), the solenoid fires. Also, should the engine coolant switch detect a higher than normal engine temp (summer time, grid lock, stop and go traffic), that will fire the solenoid.

So, you can't test/verify the solenoid's operability by simply toggling the gas pedal. You ALSO have to shift the transmission into high gear (3rd or 4th with a manual tranny car) to re-activate the solenoid once the engine is warm and running normally.

[Patrick Hulst (16386)]

Wrong part, Jack.

Jack,

You're talking about a different part.
He states that the ACTUATOR on the left front of the carb is not working well. You went off on a discussion of the solenoid located on the right side of the intake manifold.

Two different parts and different functions.

Patrick