TCS Spark Solenoid

[Raymond W.]

The '73-'74 TIM & JG notes that a tube connects to a "green" T-connector on manual transmissions and/or a "white" T-connector on automatic transmissions. I have a '74, LS4, manual trans and have seen what is described to me as an NOS GM TCS Solenoid, part number 1997411 (correct for my car), but the T-connector is white, as is the plastic cover around the electrical connection and foam filter. Should the T-connector on a solenoid that is correct for my car only be green? With the use of "and/or" in the manual description, were the colors of these T-connectors ever interchanged between manual and auto trans solenoids? Is my original description that of a repro...? Need some help. Thanks.

[terry westrick]

Re: TCS Spark Solenoid

I have a late (June) 73 454 manual that has the green T.

Terry

[Geoff C.]

[Joe L.]

Re: TCS Spark Solenoid

Ray------

I tend to agree with Geoffrey. However, I'll add this which is pretty much supposition on my part. In PRODUCTION, 4 different TCS solenoids were used for 73-74 Corvette applications. GM #1997411 is the correct one for 73-74 with LS-4 and 4 speed. Others were used for LS-4 and automatic, L-48 with 4 speed, and L-48 with automatic. As far as I know, none of these were "interchanged" or "alternately used" for applications other than the specified applications.

It MAY be that in PRODUCTION, the plastic components of the solenoid (i.e. the part you're referring to) were color coded as an aid to easy and quick identification by assembly line personnel. I don't KNOW that this was the case, but I wouldn't be surprised if it was. The color-coding may or may not have been accompanied by a broadcast code sticker or it may simply have supplanted the need for a broadcast code sticker.

In SERVICE, there would have been no need for the color coding and GM may have dropped the requirement, possibly at the request of the manufacturer. You see, in SERVICE a far small quantity of these things would have been produced and the manufacturer may have wanted to consolidate the plastic components so that they didn't have to make up "short runs" of identically configured components, differing only in color. It may also be that in SERVICE or PRODUCTION, random plastic colors were used at the whim of the plastics formulator, as Geoffrey mentioned.

If what I'm hypothesizing is the way it was, then what you have may be a SERVICE part that was manufactured without regard for color coding, if color coding was ever a specification for the parts, at all.