More Than One 70 TCS Relay?

[Terry M.]

Re: More Than One 70 TCS Relay?

The TCS relay for my 70 SB 4-speed has three prongs on it, and I believe it's original to the car, even with a correct date. It is part number 3961573.
There's an auction on ebay in which the seller claims to have a relay with this same number on it, yet it has four prongs. The pictures are fuzzy so it's hard to confirm the numbers:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=330310244038&sspagename=STRK%3AMEWAX%3AIT&viewitem=

So did the 3961573 relay come in both three and four prongs? Maybe the four-prong is for an auto or different engine?
Thanks

I don't know how much this photo will show, but there are four prongs. One, the short one, is unused -- nothing goes over it.

The connector has a tab that extends over the edge of the relay, so that is what keys the two-pole connector. As far as I can see there is no key for the single wire connector.

https://www.forums.ncrs.org/attachme...00176&uid=5254

[Jim T.]

Re: More Than One 70 TCS Relay?

I know that my 70's is the original unit and it is black.

[Chris G.]

Re: More Than One 70 TCS Relay?

I have my original 1970 TCS relay with 4 posts. The short post is NOT an electrical connection. Why you are seeing only 3 posts (2 long and 1 short) means that your main power post looks like it is broken off, and you have been using the other short post instead. It might be working because they are both connected via the same metal part along the bottom. I have been spending the last 2 weeks trying to get my TCS system to work properly, and all this looks very familiar! I am assuming that the relay is working?

[Roberto L.]

Re: More Than One 70 TCS Relay?

I think you are right, Patrick's relay has a broken post, that solves the mystery. As it is the one which shares continuity with the short post the solution is to connect the one wire connetor to it.

Now, I don't understand your last sentence. You want to test the relay?

Best regards

[Chris G.]

Re: More Than One 70 TCS Relay?

No, I don't want to test the relay, I was just asking a question if the relay works with the broken off post, if it is broken off?

[Pat M.]

Re: More Than One 70 TCS Relay?

It's certainly possible one post broke off, but if so it broke so cleanly you cannot tell one was ever there.

My relay worked fine even with just three posts until very recently. Even though I could've just replaced it with a new one (you can still get the correct kind from Paragon, among others) I decided to try to fix it and I think I did. It's really interesting how it works, and, assuming my fix holds, I may submit a Restorer article on it, and I took a lot of great pictures.

It just makes me feel better to be able to re-use a part I believe the car was born with.

[Roberto L.]

Re: More Than One 70 TCS Relay?

No, I don't want to test the relay, I was just asking a question if the relay works with the broken off post, if it is broken off?

I understand, well you said it. The short post and the missing one are one common electrical point and there is no problem connecting the wire to one or the other, but the correct post is the longer because it makes a firmer and locking connection If I'm right.

Best regards