theblackvette

Thread Inspired by Chief War Bonnet


I was out today and away from the RED DRAGON and I couldn't stop thinking about the CEC system that was asked about by Chief War Bonnet regarding specifically to my car. We made this discovery last weekend that there are items related to the system that are still in the car. This is a really nice find. I was told a lot of these 1971 only systems are completely out of the cars. I recalled all day that it was present (I don't know if all or in part) in my car. Well I just got home and the first thing I did was pop the hood and take the air filter off and takes some pictures to share. I did not take any pictures last week but I really wanted to get inside it all day to show you what is in the car.

Any idea on how I can get this working again?

gq82

I have a working CEC system on my 71 and it's pretty complicated. This article by Jack Humphrey is the most comprehensive one I've ever seen

Scroll down through the NCRS chapter news letter until you see the article 1971 Corvette Emissions System (pg 4)

Happy reading.

http://ncrsrmc.org/Downloads/Mar-2006-Newsletter.pdf

BTW, by the look of your pictures it might be working.

theblackvette

Thanks for the link!!!!! I am gonna check it out.....

Yeah, we did not test to see if it was operational. It was simply to determine if the system was even present. We spent little to no time on it. But, going with the odds I was told chances are it is not working and will deal with it later when the time comes.

I am glad it is there and your statement that it might be working is very encouraging.

Alan 71

Hi BV,
In addition to the solenoid mounted on the carb there were 4 other components to the CEC system.
2 mounted on the firewall; a reversing relay and a delay timer, a temperature sensor in the right side head, and a sensor in the transmission that relayed to the the solenoid when the transmission was in 3rd and 4th gear.
The solenoid in your picture has it's electrical connection and 2 vacuum hoses in place which is a good start.
You may want to check that the other components are there and that they have electrical connects in place.
The system is pretty neat when it's working and was really a fore-runner to a computer controlled emissions system.
There is an Operations Item for it, and the Mechanical team checks for the other parts.
Regards,
Alan

The reversing relay, (forward), and the delay relay (close to the fire wall), with a electrical connection for each. There were several configurations to the delay timer so they don't all look the same.





The electrical connection for the temp sensor in the right hand head.



Sensor in transmission; lower left side near bell housing.

theblackvette

Alan thanks so much for checking my set up and giving me some helpful notes. As much as I want to pull off the air filter and and all and get busy with it I think I need to leave this one to someone who knows what there are doing.....

I am cuckoo for cocoa puffs and I don't trust myself with this. Knowing me I will short out the entire car doing something stupid. This is all electrical stuff and I took some physics but I don't remember much of it except to stay away from it if you don't know what you are doing.

I am going to go back out to the car and take a look at that relay you are referring to and see if it is there.

But I am certainly going to read up on it. I just find it interesting Chief War Bonnet had brought this to my attention this morning and by coincidence I had briefly looked at this item last weekend.

I am so glad it appears to be there and MAYBE in working condition.

theblackvette

Alan I went out to the car and took this snap shot.

Here is what I found! I didn't touch a thing. Only snapped a picture.

Dan H.

Could you post a link to an article for war bonnet? I'm interested to learn more about this.

I was setting my timing last weekend and found I was getting no vacuum advance after this solenoid but it was working leading into it. After reading I see it only activates and sends vacuum in 3rd ad 4th gear. Seems weird, but thats what the service manual says....

Mick71

I always wondered what that wire on my transmission was for.
Thanks.

theblackvette

I do not think WB knows this thread exists, yet. I think he will be pleasantly surprised.

As for a link...do you mean something like this? Best regards.

http://ncrsrmc.org/Downloads/Mar-2006-Newsletter.pdf

theblackvette

I don't know if you are joking but if you are serious glad this thread helped you out.

Mick71

No joke. I also wondered about the rest of this system, too. It's all there and hooked up, I just didn't know what it does or how/if it works on my car.

theblackvette

Absolutely fantastic! The thread just paid for itself. I like this is a one year install on 1971 corvettes. Just like the gas cap. Have you checked your gas cap to see if it is original?

Mick71

It is not, but I'm lucky to have most of the original parts on my car.

LeMans Pete

Completely off-topic (I know BV doesn't mind), but Alan you have photos of everything, and they are always perfectly in focus and very well detailed.

CraigH

Have a look at this thread as well.

http://forums.corvetteforum.com/c3-t...-wiring-2.html

The NCRS article still left some things unexplained in my mind .

theblackvette

Ah I read that a way to test it is to put the key in the on position and depress the petal and you should hear the system engage. I guess this may be how the system is checked during ncrs judging perhaps?

Alan 71

Hi BV,
The operations check for the CEC system has steps in it that check that the solenoid is operating when the engine is cold which brings the engine rpm to a higher level than the choke alone would, and also at normal operating temperature; that the reversing relay is operating when it receives the signal from the temperature sensor; that the delay timer is operating when the engine is warm and the engine is re-started; and that the sensor in the transmission is sending the proper signal to the solenoid which raises the rpm at idle when the transmission is shifted into 3rd and 4th gear and the engine is warm. To test these 4 functions the engine must be cold to begin the check and then run long enough for it to reach operating temperature.
Some owners confuse the effect of the automatic choke has on the engine when cold and at operating temperature with the operation of the CEC system since the both affect the engine rpm, but in quite different ways.
Many operations team members do other parts of the operations check while waiting for the engine to warm up… especially those items that may require the engine to be running.
Regards,
Alan

theblackvette

As I was reading your explanation I was thinking I know exactly what you were talking about regarding engine rpms bring increasing at start. Mine does this but then I read your closing sentence and my hopes of confirming if my solenoid is working were dashed. I may be in the confused owners group. O well but I am getting closer to finding out though. Thank you.

Alan 71

Hi BV,
The last function is easy (maybe the easiest) to test.
When you're sitting in the car at idle (engine completely at operating temperature) shift the transmission into 3rd and 4th gear leaving the clutch pushed in, the idle speed should increase about 500 rpm in each gear. As soon as you move the shifter back to neutral, or 1st or 2nd gear, the idle should return and stay at the normal idle rpm for your car.
Regards,
Alan

theblackvette

Okay looks like I have an assignment later to do. If mine works this will be something else. I am expecting it not to work but I am very pleased the original hardware of the system is in the car and that is of most importance.