Topic: Sealants used at quarter extension and trunk - 65 SJ

[tvor]

Hi all,
I read an earlier post about the seals that mount on the studs of the quarter extension.  When I took mine apart, it looked like there was sealer on both sides of the flat washer.  Is this the case?  Also, is there anyone that sells just the sealer washer (AMK  B-13742)?  My hardware is fine and I plan on reusing it. Also, on my car, it looked like there was some kind of sealer or rubber bumper on the edge of the car for the quarter extension.  Anyone know what this is? 

In the trunk, can someone tell me what product was used to caulk the joints where the wheel well and the trunk floor meet?

I've read about "dum-dum"; what is it, where was it used and can it or a similar product be purchased?

Thanks for all help on these questions!

[J_Speegle]

Hi all,
I read an earlier post about the seals that mount on the studs of the quarter extension.  When I took mine apart, it looked like there was sealer on both sides of the flat washer.  Is this the case?

Are you referring to the washer that is part of the nut assembly that attaches the quarter extension to the car ? If so the sealant was on between the back of the nut and the body and was compressed as it was tightened Don't believe the sealant was made and applied to the back of the washer and delivered to the factory that way. The sealant on the washer you are showing looks like its been applied to the back side and rolled around the edge as it was compressed. Just add the 3M product mentioned below and install

Also, on my car, it looked like there was some kind of sealer or rubber bumper on the edge of the car for the quarter extension.  Anyone know what this is?

If your not building a 64 1/2 then there should be a small thin weatherstrip channel around the outer edge of your quarter extensions that held a thin rubber strip. These are available in reproduction from most parts shop.

One example

http://www.virginiaclassicmustang.com/65-73-QUARTER-EXTENSION-GASKETS-67-70-HEADLIGHT-BUCKET-ASSEMBLY-GASKETS-PAIR-P4378C1205.aspx

 

In the trunk, can someone tell me what product was used to caulk the joints where the wheel well and the trunk floor meet?

Any good black elastomeric chalk will do that is smooth (no texture added) and will handle the climate changes without cracking. Hopefully you took pictures of where and how yours was originally applied. Most builders/restorers have their favorite brand and method of applying it to get the "factory look"

I've read about "dum-dum"; what is it, where was it used and can it or a similar product be purchased?

3M strip chalking is what is commonly used in black. Available through many of the parts suppliers, your local paint store and over the internet

[tvor]

Thank you Jeff.  Yes, mine is an early '65.  It is a transition car, but with many more of the 64 ½ parts than '65 (door tag says 9/11/64).  I do have the nut assembly that your picture shows.  However, I dug out a flat washer inside of the conical washer/nut.  The sealant could have very well squished behind the flat washer, but the sealant was all the way behind the washer (no voids).  What really puzzles me is why there is a flat washer to begin with.  Any ideas?  I am 99% sure that it came from the factory like that.  The car has been in the family since new and I know its history.

My extensions do not have the channel for the seal, that's why I was wondering what the blob of rubber or mastic was in the hole on the edge of the quarter panel.  In your picture, it looks like you have it too!  Bottom left in the pic.  Any idea what that hole was for?  Is the mastic applied during or after install?

Thanks so much for your help.

Kelley

[J_Speegle]

Thank you Jeff.  Yes, mine is an early '65.  It is a transition car, but with many more of the 64 ½ parts than '65 (door tag says 9/11/64).  I do have the nut assembly that your picture shows.  However, I dug out a flat washer inside of the conical washer/nut.  The sealant could have very well squished behind the flat washer, but the sealant was all the way behind the washer (no voids).  What really puzzles me is why there is a flat washer to begin with.  Any ideas?

What assembly plant?

Could just be a worker that placed them there on their own or a practice that was used and later dropped when it was determined that it was not needed.  Did you look at the unibody (don't know where you are in the build - sorry) to see if there was a strong coat of paint under where the extension would be installed or if there was a shadow in that area?

My extensions do not have the channel for the seal, that's why I was wondering what the blob of rubber or mastic was in the hole on the edge of the quarter panel.  In your picture, it looks like you have it too!  Bottom left in the pic.  Any idea what that hole was for?  Is the mastic applied during or after install?

Not sure why the engineers put the hole there might be for alignment in a jig used to assemble that panel and one or more - making it a sub panel that would have been added to other panels during the assembly of the basic body

Unibody was sealed, primered and painted then the blob of mastic was applied not that particular lump is not painted. It is unrelated to the style of end caps

[tvor]

What assembly plant?

Could just be a worker that placed them there on their own or a practice that was used and later dropped when it was determined that it was not needed.  Did you look at the unibody (don't know where you are in the build - sorry) to see if there was a strong coat of paint under where the extension would be installed or if there was a shadow in that area?

My car is from the San Jose plant.

On the unibody where the extension mounts, it looks like a light grey primer and an outline of color (poppy red).  Looks like the extension was installed and then painted at the same time as the  car as a complete assembly (see pic 2)

As to where I am on my progress, I recently took it to the body shop for body work and paint.  For warranty on the paint job, they require to do the body work.  I could have knocked out some of the dents, but I'm getting anxious to get the car done and back on the road. They can get it done much quicker than if I tried to do it (I did do 2 small dents all the way out with no use of filler tho'  )

Thank you for your help.
Kelley

[CharlesTurner]

I believe the original washers/nuts had sealant applied to them and were delivered to the assembly plant that way.  Had some very old NOS service replacement quarter extensions and had the nuts that way also.  Keep in mind that there are 2 styles of the nuts, 65 and some or all of 66 is smooth about the washer edge, plain zinc or cad plating.  The later style, like which would be found on 67-78 are zinc with dichromate and have wavy edges.  Bob P has a big bucket of these from the Dearborn assembly plant.  AMK also makes a nice reproduction, but unfortunately, sell them as "correct" for 65-66, which does not match what I've seen on original cars.

[tvor]

Thank you Charles.  I'm lucky enough to have had this car in the family and know that most of all the hardware is factory.  I do have the wide washer that is attached to the nut.  The washer has smooth edges.  I'm going to go with Jeff's suggestion and use the 3M strip caulk.  It looks like it's the same material.
I have a hunch that the factory had precut mastic to fit the stud (AMK has "mastic washers") to help speed up installation.  I've got time, so the strip stuff should be good

Thank you for the additional info as well.
Kelley

[CharlesTurner]

If you use strip caulk on the face of the nut washers, I recommend to roll out the caulk and cut "washers" to match the diameter and 1/16" - 1/8" thick.  When tightening, this will give the desired appearance with the caulk squishing out. 

[J_Speegle]

My car is from the San Jose plant.

On the unibody where the extension mounts, it looks like a light grey primer and an outline of color (poppy red).  Looks like the extension was installed and then painted at the same time as the  car as a complete assembly (see pic 2)

My current understanding is that some of the sealant was used to hold the extension on the car but away from the body for exterior pant.

With normally one nut installed but not tightened to keep it from possibly falling off. Then the extensions were tightened and fully installed after the car was painted

[jwc66k]

My current understanding is that some of the sealant was used to hold the extension on the car but away from the body for exterior pant.

With normally one nut installed but not tightened to keep it from possibly falling off. Then the extensions were tightened and fully installed after the car was painted

If that was the assembly/paint procedure, how and when did the seal, C5ZZ-6527802-C, get installed on the rear extension? I find it difficult to believe that Ford would partially install an item for paint only to remove it for a seal. It's possible but it involves two additional steps.
Jim

[J_Speegle]

If that was the assembly/paint procedure, how and when did the seal, C5ZZ-6527802-C, get installed on the rear extension? I find it difficult to believe that Ford would partially install an item for paint only to remove it for a seal. It's possible but it involves two additional steps.
Jim

Of course the very early car didn't have the seal - and during that time at some plants, it appears that they were not in place (no shadow)

Jim - can't always explain why. Con only explain what the evidence shows us.

Only way the evidence makes sense at this point - painted studs - lack of paint on the back side, lack of paint on body under the extensions, single painted nut.....

Guess they might have had a fixture that the extensions were bolted to but then it does not explain the shadow on most bodies nor have found any workers that described such a thing

[jwc66k]

Only way the evidence makes sense at this point - painted studs - lack of paint on the back side, lack of paint on body under the extensions, single painted nut.....

If I was a methods engineer looking for a better way, I would attach the three studs to the extension and then apply paint. The studs would be the "paint fixture". If I was a body painter, I would concentrate on the exposed body, not the area covered by an extension, which is what I've seen on a few cars, overspray on the extension area. The seal and two washers would be sub-assembled and the extension attached. Calking on the nuts and the tooling hole as part of the last step. The painted nut is a puzzlement.
Jim