The Ford Barn

russcc · 12-30-2020, 07:16 PM

An experienced restorer has been helping me on some tasks on the '40 coupe. I asked him about the best way to install the trunk seal using 3M's Weatherstrip adhesive. When he tried the seal on '40 trunk edge, he suggested checking to see if it was the correct seal for the '40 Coupe. I does not look like the seal we removed from the trunk.I bought it from Joe's, and it was listed as 39-40 coupe trunk seal 91A-07243720, although they also used the part # 91A-713540 on Joe's invoice. I has DC in the corners, MFG USA. Maybe they changed the way the seal is Mfg., so it looks different. Here are several photos that may help confirm it is the correct one.

19Fordy · 12-30-2020, 09:13 PM

Here's the trunk seal for the 40 coupe and more. Looks like they sent you the wrong seal.
I used the Drake seal on my coupe trunk.
https://www.bobdrake.com/SearchForm....0&searchtype=0

russcc · 12-31-2020, 08:12 PM

I believe Carpenter's seal # 91A-7243720, and Drake's 91A-713540 are the same, with different #s, and likely made by Carpenter as it has DC Mfg. USA on it. Both illustrations, as poor as they are look the same. There is thick side and thin side of the slot in the seal.
If the seal slot fits on the sheet metal flange around the trunk, which side faces up toward the trunk lid, thin or thick. See photo of trunk flange.

19Fordy · 01-01-2021, 10:00 AM

Here's some photos that will help. Thick side faces up towards trunk lid to provide the sealing effect. Thin side hooks around lip. I don't recall, but I don't think I applied any adhesive as the seal fit nice and snug. Looks nicer if you miter the corners although I am not sure that's the way Henry did it. I bought the adhesive to join the mitered corners shown in 1978. Don't know if it has been updated with a new part number.

russcc · 01-01-2021, 07:21 PM

Thank you 19Fordy. It appears in the 4th & 5th photos that the thin side of the seal is facing up. That is how the seal I got from DC fits. I wonder if the thick side actually seals against the edge of the trunk lid. Here are several photos of the DC seal, (bonded corner), the trunk flange and the seal installed on the trunk flange with the thin side facing up, (it's the only way it will go on. That got me to thinking the trunk lid may seal on the side of the seal as that is the fat side that is exposed just below the flange.

19Fordy · 01-01-2021, 08:57 PM

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Here are a few more photos I just took. In photos 1,2 5 and 6 you are looking at the trunk lip as viewed from inside the trunk on the driver side with the thin metal lip showing. Photos 3 and 4 are the views from outside the trunk. There is a small amount of adhesive sealant shown in photo 2. The thin side of the seal fits over the sheet metal lip on the perimeter of trunk opening. Note: As I recall the seal is longer than needed so you can cut off a short piece and "test fit" it. The yellow stuff looks like I did use some 3M weatherstrip adhesive.

russcc · 01-03-2021, 09:45 AM

Thank you again 19Fordy. 1st, it looks like the new seal I have is different than the one you used, as it fits as is without having to cut and glue, and has bonded corners. Also, in the 6th picture looking at the driver's side from inside the trunk area that the fat part of the seal is below the flange, and the thin side of seal sets on top of the flange. Please correct me if am wrong. If so, that's how the seal from DC fits. Also, the restorer told me to use 3M black weatherstrip adhesive.

19Fordy · 01-03-2021, 11:00 AM

You are correct. To feel entirely comfortable install the seal with no adhesive for a literally "dry run" and check the fit.

russcc · 01-03-2021, 07:01 PM

I have installed the seal without the adhesive and it looks ok. I had the trunk lid off to do some other work. I may put it back on to check how the seal fits, but I expect it would be easier to install the seal without the trunk lid. Opinions ?

19Fordy · 01-04-2021, 09:00 AM

I installed my seal with the trunk lid on the car. That way you can close the trunk which compresses the seal into position for the best sealing effect and also allows the adhesive to 'squish down" for the best fit under the pressure of the closed trunk.

russcc · 01-04-2021, 10:07 AM

Thank you again. Good point, I will put the trunk lid back on.

Bluedot · 01-09-2021, 09:47 PM

Be very careful closing the lid if the adhesive is still wet. Easy for the seal to wiggle or squirt out of position, and then you have the hassle of a re-do. I HATE do-overs!
Solution: A strip of masking tape across the seal every 8- 10 " or so will hold it where you want it. Then if you wanna close the lid to compress the adhesion, the seal stays put.

V8 Bob · 01-10-2021, 11:22 AM

I've had the one-piece Bob Drake trunk seal in place on my '40 coupe for several years during construction and like the fit and quality. I started final assembly last March when all the painted body and parts were brought home from the body shop, and thought it would be much easier to finally glue (3M) the trunk seal in place with the trunk lid off because of easier access, imo.

19Fordy · 01-10-2021, 02:28 PM

On is better because trunk lid applies continuous even pressure for curing of adhesive.

However, "off" probably works also unless install is not meticulous.

russcc · 01-10-2021, 06:39 PM

Because I had the trunk lid off, I did that way because of the access. At the top, i used several thin pieces of wood along side the seal to push into the bottom of the channel, and masking taped them in place. Along the sides & bottom, I used round lengths of "caulking saver" masking taped in place to hold the seal into the channel. It came out great. Before I applied the adhesive I set the seal in place with masking tape for several days to get the kinks out of it. I also marked on the car, and seal center line sat the top & bottom to ensure it was lined up right when I out the adhesive on the. The black 3M adhesive worked great, and became tacky within several minutes of being exposed to the air.

12-30-2020, 07:16 PM	#1
russcc Senior Member Join Date: May 2010 Posts: 2,871	'40 Trunk seal 91A-7243720 An experienced restorer has been helping me on some tasks on the '40 coupe. I asked him about the best way to install the trunk seal using 3M's Weatherstrip adhesive. When he tried the seal on '40 trunk edge, he suggested checking to see if it was the correct seal for the '40 Coupe. I does not look like the seal we removed from the trunk.I bought it from Joe's, and it was listed as 39-40 coupe trunk seal 91A-07243720, although they also used the part # 91A-713540 on Joe's invoice. I has DC in the corners, MFG USA. Maybe they changed the way the seal is Mfg., so it looks different. Here are several photos that may help confirm it is the correct one. Last edited by russcc; 02-22-2021 at 01:17 PM.

12-30-2020, 09:13 PM	#2
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,925	Re: '40 Trunk seal 91A-7243720 Here's the trunk seal for the 40 coupe and more. Looks like they sent you the wrong seal. I used the Drake seal on my coupe trunk. https://www.bobdrake.com/SearchForm....0&searchtype=0

12-31-2020, 08:12 PM	#3
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 I believe Carpenter's seal # 91A-7243720, and Drake's 91A-713540 are the same, with different #s, and likely made by Carpenter as it has DC Mfg. USA on it. Both illustrations, as poor as they are look the same. There is thick side and thin side of the slot in the seal. If the seal slot fits on the sheet metal flange around the trunk, which side faces up toward the trunk lid, thin or thick. See photo of trunk flange. Last edited by russcc; 02-22-2021 at 01:16 PM.

01-01-2021, 07:21 PM	#5
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 Thank you 19Fordy. It appears in the 4th & 5th photos that the thin side of the seal is facing up. That is how the seal I got from DC fits. I wonder if the thick side actually seals against the edge of the trunk lid. Here are several photos of the DC seal, (bonded corner), the trunk flange and the seal installed on the trunk flange with the thin side facing up, (it's the only way it will go on. That got me to thinking the trunk lid may seal on the side of the seal as that is the fat side that is exposed just below the flange. Last edited by russcc; 02-22-2021 at 01:16 PM.

01-03-2021, 09:45 AM	#7
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 Thank you again 19Fordy. 1st, it looks like the new seal I have is different than the one you used, as it fits as is without having to cut and glue, and has bonded corners. Also, in the 6th picture looking at the driver's side from inside the trunk area that the fat part of the seal is below the flange, and the thin side of seal sets on top of the flange. Please correct me if am wrong. If so, that's how the seal from DC fits. Also, the restorer told me to use 3M black weatherstrip adhesive.

01-03-2021, 11:00 AM	#8
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,925	Re: '40 Trunk seal 91A-7243720 You are correct. To feel entirely comfortable install the seal with no adhesive for a literally "dry run" and check the fit.

01-03-2021, 07:01 PM	#9
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 I have installed the seal without the adhesive and it looks ok. I had the trunk lid off to do some other work. I may put it back on to check how the seal fits, but I expect it would be easier to install the seal without the trunk lid. Opinions ?

01-04-2021, 09:00 AM	#10
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,925	Re: '40 Trunk seal 91A-7243720 I installed my seal with the trunk lid on the car. That way you can close the trunk which compresses the seal into position for the best sealing effect and also allows the adhesive to 'squish down" for the best fit under the pressure of the closed trunk.

01-04-2021, 10:07 AM	#11
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 Thank you again. Good point, I will put the trunk lid back on.

01-09-2021, 09:47 PM	#12
Bluedot Junior Member Join Date: Aug 2019 Posts: 12	Re: '40 Trunk seal 91A-7243720 Be very careful closing the lid if the adhesive is still wet. Easy for the seal to wiggle or squirt out of position, and then you have the hassle of a re-do. I HATE do-overs! Solution: A strip of masking tape across the seal every 8- 10 " or so will hold it where you want it. Then if you wanna close the lid to compress the adhesion, the seal stays put.

01-10-2021, 11:22 AM	#13
V8 Bob Senior Member Join Date: May 2010 Location: Granger (Northern) Indiana Posts: 1,520	Re: '40 Trunk seal 91A-7243720 I've had the one-piece Bob Drake trunk seal in place on my '40 coupe for several years during construction and like the fit and quality. I started final assembly last March when all the painted body and parts were brought home from the body shop, and thought it would be much easier to finally glue (3M) the trunk seal in place with the trunk lid off because of easier access, imo.

01-10-2021, 02:28 PM	#14
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,925	Re: '40 Trunk seal 91A-7243720 On is better because trunk lid applies continuous even pressure for curing of adhesive. However, "off" probably works also unless install is not meticulous.

01-10-2021, 06:39 PM	#15
russcc Senior Member Join Date: May 2010 Posts: 2,871	Re: '40 Trunk seal 91A-7243720 Because I had the trunk lid off, I did that way because of the access. At the top, i used several thin pieces of wood along side the seal to push into the bottom of the channel, and masking taped them in place. Along the sides & bottom, I used round lengths of "caulking saver" masking taped in place to hold the seal into the channel. It came out great. Before I applied the adhesive I set the seal in place with masking tape for several days to get the kinks out of it. I also marked on the car, and seal center line sat the top & bottom to ensure it was lined up right when I out the adhesive on the. The black 3M adhesive worked great, and became tacky within several minutes of being exposed to the air.