January Built 1969 Corvette Coupe Window Felts

[Joseph A.]

I have a January built coupe. I purchased NOS door felts (3966641-2) which is the part number from the assembly manual, when I compare them to my original ones they are longer and the hole at the rear is punched in a different place. Any ideas why they are not at least the same size as they are NOS.

[Reba W.]

Re: January Built 1969 Corvette Coupe Window Felts

I believe there was a design change during 1969 production but do not know details.

Hopefully this will get back to the top of the list so maybe someone knowledgeable will answer.

[Terry M.]

Re: January Built 1969 Corvette Coupe Window Felts

I have a January built coupe. I purchased NOS door felts (3966641-2) which is the part number from the assembly manual, when I compare them to my original ones they are longer and the hole at the rear is punched in a different place. Any ideas why they are not at least the same size as they are NOS.

Joe

My 1969 AIMs (note the plural) are not readily available, but let me explain the short-comings of NOS parts. First I prefer to use the term SERVICE part because usually these parts come from the parts (SERVICE) counter of Chevrolet dealerships. The term New Old Stock (NOS) doesn't tell us where the part came from, nor, as you have found out, how it will fit the application intended. The term NOS is like Numbers Matching in that it has different meanings to different people.

That said there are also short-comings to the AIM in that they represent a given slice in time, and depending on the change box on the lower ight, the sheet may represent either early or late production. And even those changes shown in the change box may not have made it to the production line by the date(s) shown in the change box. Collecting AIMs in an effort to expand our knowledge of production changes is a rabbit hole unto itself.

When there is a design change for a PRODUCTION part the SERVICE part may, or may not, be equal to either design of PRODUCTION part. SERVICE parts are often made to fit a variety of designs, and may even equal a later PRODUCTION part. Usually SERVICE parts are made to fit the widest variety of years possible in order to extend the market, and sometimes an adjustment will be necessary to get the part to fit. Other times the part will not fit the earlier application, but in that case the parts book (Computer now days) usually states that. However, there are errors in both the computer and paper files.

This is a busy week for me, but I'll try to spend some time with the 1969 AIMs to see what I turn up for the window felts. I am more than a little curious since I own a January 20 built 1969. I am nowhere near replacing the window felts now, but it is a hill I will have to climb in the future. You could make my search a little easier if you can tell me the Section and Sheet that the window felts are listed on.

[Patrick H.]

Re: January Built 1969 Corvette Coupe Window Felts

FYI, Corvette Central does make an exceptionally nice set of reproduction window felts, in case you feel like buying a set of those.

[Lawrence M.]

Re: January Built 1969 Corvette Coupe Window Felts

1969 AIM, Window Seal ASM Outer, UPC 1 Doors, Sheet K 3.

[Joe L.]

Re: January Built 1969 Corvette Coupe Window Felts

I have a January built coupe. I purchased NOS door felts (3966641-2) which is the part number from the assembly manual, when I compare them to my original ones they are longer and the hole at the rear is punched in a different place. Any ideas why they are not at least the same size as they are NOS.

Joseph------


GM #3966641-42 are very late 1969 part numbers. I doubt that these parts would have been around at the outset of the 1969 model year. I think that early 1969 Corvettes used the same window glass outer seals for both coupe and convertible. These were GM #3954589, lh, and GM #3954590, rh. Just when the change was made (to the 3966641-42 for coupes only) I do not know but I'll bet it was after your car was built.

By the way, the 3954589-90 are 34-1/2" in length while the 3966641-42 are 36" in length. I'll also bet the former dimension matches your originals and the latter dimension matches your NOS pieces.

[Joseph A.]

Re: January Built 1969 Corvette Coupe Window Felts

Section 1/K3

[Joseph A.]

Re: January Built 1969 Corvette Coupe Window Felts

Thank you Joe

[Terry M.]

Re: January Built 1969 Corvette Coupe Window Felts

OK> Let's see if I can clarify this for all of us.

First thanks to Joe L. You always provide a bright light on questions and you did here also.

To Larry M and the OP Joe A thanks for the specific sheet data. You have no idea how much time that saves, and I needed that help.

Now for the meat of the issue: All these photos are from a 1969 AIM UPC 1, Sheet K3

Photo #1 Shows the parts in question as item 2 below

UPC 1 Sheet K3 parts drawing.jpg

Then the parts description shows Item 2 with a change indication. It is hard to read, but it is a number 5 in a circle. See below. The line for Item 2 shows 3954589 - 90 became 3966641 - 2

UPC 1 Sheet K3 Parts ID.jpg

So with that number 5 in mind we look to the Revision Record below for item number 5. (I apologize that I called this a change box in my earlier post. I just couldn't remember the correct term) Line 5 shows a REQUEST change date of 1-2-69. I highlighted that this is the request date because that date doesn't necessarily tell us the date the change took place on the assembly line. But it does give us an "on or about" date. That date is actually the date the paperwork was processed in the drafting department. There is other paperwork that would tell the assembly plant whether they could continue to use the stock of the old part number that they had on hand or if they had to integrate the new parts immediately. Regrettably, to my knowledge, we don't have access to that paperwork any longer.


UPC 1 Sheet K3 Revision Record.jpg

I hope this clarifies the AIM as much as possible. I know it is complicated, but every time I do this I thank my two years of Mechanical Drawing classes (even though they were more than 60 years ago). When CAD (Computer Aided Drawing) came into use I thought those two years were a loss. Every time I do this I am reminded that they were not.

[Joe L.]

Re: January Built 1969 Corvette Coupe Window Felts

OK> Let's see if I can clarify this for all of us.

First thanks to Joe L. You always provide a bright light on questions and you did here also.

To Larry M and the OP Joe A thanks for the specific sheet data. You have no idea how much time that saves, and I needed that help.

Now for the meat of the issue: All these photos are from a 1969 AIM UPC 1, Sheet K3

Photo #1 Shows the parts in question as item 2 below

[ATTACH=CONFIG]113147[/ATTACH]

Then the parts description shows Item 2 with a change indication. It is hard to read, but it is a number 5 in a circle. See below. The line for Item 2 shows 3954589 - 90 became 3966641 - 2

[ATTACH=CONFIG]113148[/ATTACH]

So with that number 5 in mind we look to the Revision Record below for item number 5. (I apologize that I called this a change box in my earlier post. I just couldn't remember the correct term) Line 5 shows a REQUEST change date of 1-2-69. I highlighted that this is the request date because that date doesn't necessarily tell us the date the change took place on the assembly line. But it does give us an "on or about" date. That date is actually the date the paperwork was processed in the drafting department. There is other paperwork that would tell the assembly plant whether they could continue to use the stock of the old part number that they had on hand or if they had to integrate the new parts immediately. Regrettably, to my knowledge, we don't have access to that paperwork any longer.


[ATTACH=CONFIG]113149[/ATTACH]

I hope this clarifies the AIM as much as possible. I know it is complicated, but every time I do this I thank my two years of Mechanical Drawing classes (even though they were more than 60 years ago). When CAD (Computer Aided Drawing) came into use I thought those two years were a loss. Every time I do this I am reminded that they were not.

Terry------


Yes, the AIM essentially confirms what I had mentioned. From the outset of the 1969 model year the 3954589-90 were used for all 1969 applications (note that there is no reference to coupe or convertible attached to those part numbers). Then, on 1-2-69 the 3966641-42 was added and applicable to coupes (19437) only. That would leave the 3954589-90 as still being applicable to convertibles after that time.

I expect that the date of the actual change in PRODUCTION probably did not occur until well after 1-2-69 and, likely, not for at least 45 days or more.

[Terry M.]

Re: January Built 1969 Corvette Coupe Window Felts

Terry------


Yes, the AIM essentially confirms what I had mentioned. From the outset of the 1969 model year the 3954589-90 were used for all 1969 applications (note that there is no reference to coupe or convertible attached to those part numbers). Then, on 1-2-69 the 3966641-42 was added and applicable to coupes (19437) only. That would leave the 3954589-90 as still being applicable to convertibles after that time.

I expect that the date of the actual change in PRODUCTION probably did not occur until well after 1-2-69 and, likely, not for at least 45 days or more.

Joe
I didn't have time to compare your post to the AIM. Thank you for doing that. You shed more light on the issue. I had confidence there was a positive confirmation there, so I wasn't too concerned about that. I slept comfortably in that certainty. The only down side was the alarm rang all to early, as I had to get to work.

Now over the longer term all we have to do is survey original 1969 Corvettes to find out how long the old parts were used so that information can be included in the TIM&JG. I love it when a small piece of research comes together.

[Joseph A.]

Re: January Built 1969 Corvette Coupe Window Felts

Terry my car was a coupe built the 21st of January and all the door weather stripping and window felts were the same as a convertible, also the interior door felt is the same as a 68 style with a narrow bead.

[Terry M.]

Re: January Built 1969 Corvette Coupe Window Felts

Joe
I had a feeling that this thread would eventually get to this point.

My 1969 is in storage nearly 100 miles from me pending progress on the restoration, which is proceeding at a glacial pace. I expected that sooner or later I would have to go and look at the door felts. It is a coupe as well. Being a day apart I expect we will have other opportunities to compare notes.

I have to admit my car has lead a checkered past, but I have no reason to believe the door felts or weather protection has been messed with by the six previous owners.

No promises, but I do have a reason to visit it before the snow flies, but I expect that is longer than your time frame. I'll do my best to speed up the process.