Solenoid Confusion

[81Batmobile]

I need a little help in identifying some parts here. Picture one shows the solenoid in question that connects to the EGR valve and the base of the carb. It has two hoses, or it had two, one broke off, hence I am here. The picture two shows the solenoid removed (lower left) sitting next to one I picked up a few years back. Another thread shows me the one in the upper right of this picture. My assembly manual shows the arrangement similar to the one in picture two upper right hand. The solenoid off my car matches the lower solenoid next to the red one. I can not find a red plug so I obviously have a different configuration. Pic three is the solenoid removed. Pic four is a closeup of the setup I acquired. Note the difference is a small attachment for a second hose on my original. It by the way is the piece that is cracked and pretty much useless. Is this specific to a 4-speed car?? The fact that the assembly manual shows the acquired solenoid and not the one on my vette is perplexing but I am convinced that "Corvette" is really french for "perplexing". What is this thing called?? Do I really need it, it appears to control the EGR valve in some way??

 

[GerryLP]

Ron,

The solenoids are used by the computer to apply vacuum to the EGR valve under certain condition. For example, there are two brown wires that are tied to the circuit for the torque converter lock up. When the conditions are right, for example, cruising, and with the converter lock-up energized, the solenoid applies vacuum from the carburetor to the EGR valve to perform house-keeping tasks (i.e. burn bad by-products [hydrocarbons]). I believe that when the car coasts, it will apply vacuum, but when it is climbing a hill, it won't.

It is a nifty system, for it controls the times in which vacuum is applied, and thus, it should help with economy and control emmissions at the times when they are most likely to be produced. Of course, the computer is the brains behind it.

GerryLP:cool

GerryLP:cool

 

[Peer81]

Hello Ron,

You're almost there! Change the light one for the yellowish one (that has the extra tube and you're all set to go!)

In order of display the outside (left) vacuumhose from the red solenoid goes directly to the EGR valve. The inside (right) red solenoid vacuumhose connects to the inside (left) yellowish solenoid vacuumhose with the Y connector and then connect to the front of the carb. The last vacuumhose from the outside yellowish solenoid (or the tube next to the solenoid) connects to the back airhorn of the carb. I have a picture from doc. rebuild so if you also want that just send me an pm with your email.

Groeten Peter

 

[81Batmobile]

Thanks guys, In picture 2, the single solenoid setup in the lower left came off my Vette, The two solenoid setup is an extra I picked up a while back. What you don't see is that the original has a hose connection broken off. It actually has two hoses connected to it by virtue of a small adapter that is not on the other one. Since I have a 4-speed car I think the setup with two solenoids came off a car with an automatic transmission as Gerry describes. The carb I just put on came off a vette with an automatic transmission and has an extra vacuum tube at the top of the carb just behind the secondaries. The assembly manual shows this tube connecting to the red solenoid that is not a part of my original setup. I'm going to hit the local parts dealers and Chevy today. This is another one of those little differences between a 4-speed car and an automatic car.

It's all fun!!!!

Thanks.