1974 TCS Solenoid

[Raymond W.]

I've seen photos of a '72 TCS Solenoid, GM part #1114451, which is shown as having a foam filter. Does the '74 TCS Solenoid, GM part #DR1997411, have a foam filter? Also, what kind of test could you conduct prior to installing it to determine if it's in proper working order? If a filter (which is ofter disentegrated) is a component of this part, are replacements available? (color, type of foam, density, etc). Thanks.

[Patrick H.]

Re: 1974 TCS Solenoid

Ray,

Solenoids can be tested using a small trickle charger as your source of power. Rather easy to do, and not that hard to disassemble and fix if you need to do so.

For the filter, I went to my local AutoZone, found an approprite piece of PCV type filter for an air cleaner (I didn't care what it originally was to be used for) and then cut it in an appropriate shape, about 3/4" square. I then made a hole in one end for the solenoid's port, and glued it on. Voila! NOS TCS solenoid air filter.

Patrick

[Raymond W.]

Re: 1974 TCS Solenoid

Patrick,

So when the power source is hooked up to the solenoid,...someone had mentioned that you'd hear a clicking noise if it was working properly? I haven't had experience with this before, could you elaborate more about conducting the test...and what I should expect. Based on the photo I had seen of the foam filter, I was thinking something simlar to your remedy...but wasn't sure.

Thanks, Ray

[Gary Schisler]

Re: 1974 TCS Solenoid

As Patrick said, once you find a working solenoid, you can make your own filter out of sponge material. I did this to my 72 and it passed local and regional judging. The typical sponge material is yellow but easily accepts black magic marker for a permanent dye.

You can use a battery charger set on the lowest setting (mine is 1 amp) to test the solenoid. I found two identical solenoids in a junkyard, one working one non. I took apart the non-working solenoid and found it had electrical continuity but the plunger didn't work. I took the whole thing apart, cleaned up the bore that plunger slides up and down in and cleaned it up with very fine emery paper. A drop of oil in there and now it works fine.

Gary

[Patrick H.]

Re: 1974 TCS Solenoid

Ray,

Gary taught me how to rebuild and test solenoids (see below) with a little hands-on instruction at his home one day. I can't recall, but I believe ground is to the solenoid bracket and positive goes to one of the prongs for the electrical connection of the solenoid. (If not that, then each goes to a prong.) When it works, you'll hear (and feel) the click. I now have several solenoids for use in my cars as either spares or parts donors. "All" the solenoids are the same with the exception of the actual bracket piece which holds the solenoid to the engine, so if you go to a junkyard you can pick up some donors to use for testing and parts. Or, watch ebay for used ones.

To open, there are 4 locations where the solenoid is "crimped" onto the bracket. Use a punch to artfully "uncrimp" each one, and then remove the bracket to inspect the innards of the solenoid. You may be able to resurrect one by cleaning the parts inside IF you find ahead of time that you have continuity between the two electrical prongs of the solenoid. If you don't, I find soldering the copper wiring inside a PITA so I look for another one to use.

The foam I found was in black, not even yellow as Gary mentions below, so I didn't have to use anything to color it.

Patrick

[Harmon C.]

Re: 1974 TCS Solenoid

Patrick

"All" the solenoids are the same with the exception of the actual bracket. If they are all the same I wonder why in 73 their was four part numbers for the small block and the brackets were the same and used the same intake bolt. Their was a 4 speed and automatic part number for both the L-48 and L-82 . Lyle

[Gary Schisler]

Re: 1974 TCS Solenoid

I will take a W.A.G. here that the part numbers may differentiate between the mounting methods and location. For instance, in my salvage yard journeys, I found two different GM cars with nice looking solenoids. I bought them and took them home. Both solenoids were identical to the original one on my 72 LT1 with the exception of the mounting bracket. I noticed that the mounting bracket on one solenoid had two part numbers. Although the orientation of the bracket was different than that on my LT1, it had the right part number. Further investigation revealed that, if I took the bracket off of the solenoid, reversed it and remounted it, then the configuration was identical to my car. In that configuration, the correct LT1 part number was showing. Just an observation.
Gary

[Patrick H.]

Re: 1974 TCS Solenoid

Gary,

Yes, I know that the 1970 and 1972 base motor solenoids are the same with the exception of the orientation of the bracket. I've never figured out why they changed it, as I think the 1970 orientation "looks" better. I would not be surprised if it's the same for the LT-1.

When I say "all" the same, I'm referring to those with 2 ports in "L" configuration out one end and one port out the other.

I have "yet" to see one that differs from that, but I have not seen them all.

Patrick