1940 Trunk Lid Stay Catch Spring Replace

[Daves1940Buick56S]

 

Since I have a coupe, I have 2 stays (Group 12.203). One never worked properly, so I 'temporarily" removed it 3 years ago. I finally got around to it this week, and, as many have found, the small catch spring was broken. Since the stays were sold as a unit, no separate part number for the spring is called out. chevsofthe40s.com does list this as part 4085735 but it is currently out of stock since they are waiting for enough buyers to make a run.

 

I figured the part was spring steel and I could probably make one. I disassembled the stay and fortunately had 1/2 the old spring to take measurements, especially thickness. I ordered a similar-to from timesavers.com, then cut to size. It works great. Procedure below.

 

1. Remove stay from vehicle, detaching decklid side first, then rear bolt on body end bracket, then swing down and remove front bolt.

2. Drill out rivet on decklid end.

3. Take slide assembly apart, sliding inner slide down in the opposite direction when unit is installed on car. Now it becomes clear why the rivet needed to be removed. First apply oil or WD40 to help the process along. Even so the inner slide may have to be driven out with a drift.

4. The photo below is of the spring and is taken from the chevsofthe40s site.

5. The photo below shows where the spring mounts on the inner slide. The slide is laying on a print of the above image. The spring actually goes on reverse left to right from the picture (long side to the left). The small elevated part of the spring in the center is meant to go above the small tang on the slide itself.

6. To make the spring, I ordered a small 30 hr mainspring from timesavers.com. Part number 17519. This spring has the same 0.020" thickness as the original. Picture below.

7. If you decide to unwrap the whole spring, be careful! Even though it's small, it could still explode into your face. Much safer is to carefully extract about 6" from the center and cut. Use a good pair of tin snips or aircraft snips.

8. Carefully cut the piece about in half lengthwise. If you don't have a good, sharp pair of snips you may encounter trouble here. Make sure the piece fits inside the inner slide runner.

9. If you have part of the old spring, using that and the picture of the spring above can be used to cut to the proper length, or roughly anyway. roughly bend the spring as shown in the pic. Try to bend in the elevated portion, it makes install easier. Don't kink it or you have to start over. See below. Remaining piece of old spring is on the bottom in the pics.

10. Clean up the slides, try to straighten out any bumps or kinks, and wirebrush to remove all crud.

11. Install new spring, carefully working center of spring over the tang. Check for centering, it will be obvious where it should be.

12. Lightly lube the inner slide and reassemble.

13. Test for functionality. Make sure new spring doesn't hang up on the sides. Pic below.

14. Replace bracket on formerly riveted end with screw (at least #10) and washer/nut. Reinstall in vehicle, using step 1 in reverse order.

 

[Guest]

Bought nos springs from eBay and installed in both struts for my friend Norm with a 1939 Special convert. Was able to develop a technique that worked without disassembly. Was thinking about posting pix of how, but didn't know you could fab springs like that and pair that were purchased came up on eBay and were nos. No more ever showed up, so I figured waste of time. Now I have to learn that spring making thing from Dave's post, as the old springs wear thin and break apart commonly after only 50 or so years. Nothin' lasts eh? Took about 10-15 mins to pull out old spring material with needle nose and install new spring per strut and lube. Figuring out how took longer, however! Thanx for the heads up Dave! You've helped solve a problem frustrating a lot of folks with these. I think the struts are same cpe and Cnvrt/cpe 1937-38-39-40 all series GM. Memory? Caution! Springs are not symetrical go in one way originally. May not affect function, but I checked orientation when removing and installed same direction on reassembly.

Edited January 27, 2017 by Guest
Dim bulb! (see edit history)

[1940TORPEDO]

Chevs of the '40s does have 7 of these in stock at the moment. Thanks for this post! My Pontiac is needing some of these to make her happy again.

 

[tly410]

Just for info an update on availability,  On 4-5-17, I called and checked Chevs of the 40's to find they are out of stock on this item, with no idea when or if they will be back in stock    

[Guest]

4 hours ago, tly410 said:

Just for info an update on availability,  On 4-5-17, I called and checked Chevs of the 40's to find they are out of stock on this item, with no idea when or if they will be back in stock    

Called Will, he said, yes we have seven showing in stock and we have to call the HUNDREDS on the list for that part 1st and wait 4 responses! Wow! Like Im gonna hold my breath for that! Dave, youve got a hellava opportunity here, start up the factory!

[Daves1940Buick56S]

You know you might have an idea there. Their price is $20 ea, I wonder if I would get any takers at $7 incl shipping? The only hesitation is the resiliency of the clock spring in the way I am using it, IOW how quickly they might break.