1973 Throttle Stop Solenoid

[Tom K.]

Hello All,

Back again with questions, this time about my throttle stop solenoid. I recently had my Quadrajet rebuilt and the guy did a real nice job, but he did not have the ability to work on the throttle stop solenoid. I thought I found one on EBay but when I received it the flat on the threads is 90 degrees off from my original and this points the electrical connection in towards the carburetor. I tried looking for a part number in the J/G and my AIM but there is nothing listed for the solenoid itself, only the whole carburetor assembly. Also there is no part number that I could find on my original solenoid. Tried looking with a magnifying glass in case the number was ink-stamped and faded, but no luck. If it helps, the car is a '73 with 454, A/C, Automatic, PS, PB, PW

1- Does anyone know the correct P/N for this part?
2- From the wiring diagram, it looks to me like it is an anti-dieseling solenoid rather than an idle step up solenoid, is that right?
3- It looks to me like I could dis-assemble the original and tumble the housing to clean and replate it, what is the correct plating?

As always, thanks in advance for any help!

Tom Krause

[Jimmy P.]

Re: 1973 Throttle Stop Solenoid

Tom,
The part number for the 73 LS4 Idle -Stop(anti-diesel) Solenoid can be found in bold type on page 194 in the 3rd Edition of the 73-74 TIM&JG.
Its 1997417. The part number for the small block Solenoid is also listed...1997409. We found that the part numbers weren't always stamped on the Solenoids. Some had them etched in, and some had a black ink stamped part number, more commonly found on service replacements and most had no number. The units were cadmium plated, also mentioned in the manual. I've included a couple photos from my revision files from two different LS4's from two revision team members. The first to show you how the Solenoid is mounted to the Carb, and the second from an original December 11th built '73 shows some of the part number. You can see the last four numbers 7417. It's my understanding that this Solenoid for the LS4 is pretty rare and hard to find. When you said you found one on eBay, I was thinking you were pretty lucky! I had another 73 LS4 owner tell me he got one from David Sokolowski, who advertises parts for sale on just about every page in the Driveline. He does list that he has this rare part for the 73-74 big blocks, it's actually on page 24 in the latest Driveline. But he has the part number as 1997411? Might be a typo!
Hope this helps.

[Tom K.]

Re: 1973 Throttle Stop Solenoid

Jimmy,

Thank you! I was looking through the Carburetor Section (pg 121-124) and ASSumed it would be there. I should have kept digging. Now that I have the number I will start looking for the correct item. If they are hard to find, I think my original can be taken apart and replated. The steel body of the original looks like it was zinc plated without the dichromate conversion. Im not so certain of the cast nose piece. The original looks like it was zinc plated with the dichromate also, but its hard to be sure because of its age. Every one for sale I have seen pictures of looks like it has the dichromate.

Again, Thanks for pointing out my mistake in finding the number. I never would have thought to look under chassis - now I have a bunch more reading to do!

Edit - I should have said the original steel nose piece looks like it was zinc plated WITHOUT the dichromate
Tom Krause

[Jimmy P.]

Re: 1973 Throttle Stop Solenoid

Yeah Tom,
The solenoid is judged under AIR and Other Emission Controls on the 73-77 Scoring Sheets under CHASSIS. So that's why we discuss the solenoids in the manual CHASSIS Section just to be consistent.

[Joe L.]

Re: 1973 Throttle Stop Solenoid

Hello All,

Back again with questions, this time about my throttle stop solenoid. I recently had my Quadrajet rebuilt and the guy did a real nice job, but he did not have the ability to work on the throttle stop solenoid. I thought I found one on EBay but when I received it the flat on the threads is 90 degrees off from my original and this points the electrical connection in towards the carburetor. I tried looking for a part number in the J/G and my AIM but there is nothing listed for the solenoid itself, only the whole carburetor assembly. Also there is no part number that I could find on my original solenoid. Tried looking with a magnifying glass in case the number was ink-stamped and faded, but no luck. If it helps, the car is a '73 with 454, A/C, Automatic, PS, PB, PW

1- Does anyone know the correct P/N for this part?
2- From the wiring diagram, it looks to me like it is an anti-dieseling solenoid rather than an idle step up solenoid, is that right?
3- It looks to me like I could dis-assemble the original and tumble the housing to clean and replate it, what is the correct plating?

As always, thanks in advance for any help!

Tom Krause

Tom------


GM classifies this part as a throttle stop solenoid. The original part number as has been reported was GM #1997417. That part was discontinued in April, 1982 and replaced by GM #1997470. The latter is not configured exactly like the original part but should be 100% functional. The 1997420 was discontinued in March, 1988 and replaced by GM #17111376. This part is configured considerably different than either of its predecessors but, once again, should be 100% functional. The 17111376 was discontinued without supersession several years ago. However, I believe that Standard Motor Products offers a replacement for those concerned only with functionality and not original configuration.

[Tom R.]

Re: 1973 Throttle Stop Solenoid

GM classifies this part as a throttle stop solenoid. The original part number as has been reported was GM #1997417. That part was discontinued in April, 1982 and replaced by GM #1997470. The latter is not configured exactly like the original part but should be 100% functional. The 1997420 was discontinued in March, 1988 and replaced by GM #17111376. This part is configured considerably different than either of its predecessors but, once again, should be 100% functional. The 17111376 was discontinued without supersession several years ago. However, I believe that Standard Motor Products offers a replacement for those concerned only with functionality and not original configuration.

Joe
Looking at 78-79, the solenoid was used soley with C60 to increase slightly the idle speed. Does this make sense?

[Joe L.]

Re: 1973 Throttle Stop Solenoid

Joe
Looking at 78-79, the solenoid was used soley with C60 to increase slightly the idle speed. Does this make sense?

Tom-----


Yes, but different solenoids were used----GM #1997461 and GM #17061769.

[Tom K.]

Re: 1973 Throttle Stop Solenoid

Thank you Joe,

As always lots of accurate info and greatly appreciated.


Tom

[Tom R.]

Re: 1973 Throttle Stop Solenoid

Yes, but different solenoids were used----GM #1997461 and GM #17061769.

What's the difference...four-speed vs. automatic? Or L48 vs. L82?

[Joe L.]

Re: 1973 Throttle Stop Solenoid

What's the difference...four-speed vs. automatic? Or L48 vs. L82?

Tom------


It's like this:


1978

L-48, C-60, M38 , NA9---------------------1997461

L-48, C-60, M38----------------------------1997461

L-82, C-60, M38----------------------------1997461

1979

L-48, C-60, M-38, Fed Em-----------------17061769

L-82, M-38, without C-60------------------17062523

L-48, M-38, C-60, Cal Em----------------- 17061769

L-48, M-38, hi alt, without C-60-----------17061769

L-48, high alt,-------------------------------17061769

L-82, M-38, C-60---------------------------17061769

L-82, M-38, C-60, Cal Em------------------17061769

1980

L-48, MV4-----------------------------------17061769

LG-4-----------------------------------------17061769

1981

All--------------------------------------------17067179


The GM #1997461 was replaced for SERVICE by the GM #17061769. The latter was replaced for SERVICE by the GM #17067179.

The unique and rare solenoid, GM #17062523, was used only for 1979 L-82 with auto transmission and without C-60. Following are some photos of an NOS 17062523 [not for sale]:

DSCN4052.jpgDSCN4053.jpgDSCN4054.jpgDSCN4055.jpg

[Tom K.]

Re: 1973 Throttle Stop Solenoid

Hello All,

As it turns out, I was able to buy a NOS solenoid P/N 1997417 for my 1973 Corvette. It just arrived today and I thought I would post the pix showing the comparison between the item that was on the car and the one I just purchased.
If you need a solenoid like this, here are a few things I have learned to look for:

1- The orientation of the flat in the threads relative to the electrical connection
2- The size and shape of the markings on the plastic piece on the back end
3- The finish of the can
4- The finish of the threaded bushing
5- The size of the hex that contacts the throttle lever
6- The connection from the internal coil to the external terminal

These are all things that I have seen variations in for parts that out there as service replacement, chain store replacement, supposed NOS etc etc. I'm sure some of you guys can add to this list.

AS ALWAYS, you guys were generous with your knowledge and a huge help with the learning curve. Enjoy the pix!

Best regards,

Tom Krause