69 Seat Adjuster

[Michael C.]

The seat adjusters on my 69 coupe don't seem to match the assembly manual or vendor catalogs. I'm the original owner, so I know these came on the car. See the attached image for what mine look like.

My question is: Should there be a rubber "cushion" on this part? I'm almost certain remember seeing the rubber tearing off as it aged. This part screws into the lower edge of the seat back and rests on a rubber bumper on the bottom of the seat when in the sitting position. Next question: If there should be a rubber cushion, where might I purchase a couple?

Thanks,
Mike

[Joe L.]

Re: 69 Seat Adjuster

The seat adjusters on my 69 coupe don't seem to match the assembly manual or vendor catalogs. I'm the original owner, so I know these came on the car. See the attached image for what mine look like.

My question is: Should there be a rubber "cushion" on this part? I'm almost certain remember seeing the rubber tearing off as it aged. This part screws into the lower edge of the seat back and rests on a rubber bumper on the bottom of the seat when in the sitting position. Next question: If there should be a rubber cushion, where might I purchase a couple?

Thanks,
Mike

Mike-----

You can use a GM #400765. These are discontinued but can still be found, either NOS or aftermarket equivalent. Search eBay on "400765". These are the complete bolt and bumper assembly. The exact same piece is used for the hood bumper on many Corvettes. You would re-use your existing flange nut and washer.

[Michael C.]

Re: 69 Seat Adjuster

Joe, so you're suggesting to use the rubber piece from this part with my hardware? I see that a number of vendors sell replacement rubber caps for the hood bumpers. These look very much like what I remember seeing as I do remember the seat bumper have a large hole in the rubber. Thanks for pointing me in that direction.

[Joe L.]

Re: 69 Seat Adjuster

Joe, so you're suggesting to use the rubber piece from this part with my hardware? I see that a number of vendors sell replacement rubber caps for the hood bumpers. These look very much like what I remember seeing as I do remember the seat bumper have a large hole in the rubber. Thanks for pointing me in that direction.

Michael------

The 400765 is, basically, a bonded assembly of the rubber cushion and steel "stem". The rubber cushion is not really removable. However, when used in place of the original separate rubber cushion and stem, it appears just about the same. The bonded piece is also much more durable than the original. If you use the 400765, the only part of your original assembly you would use would be the flanged nut and washer. Of course, you could also purchase the reproduction rubber cushions and use them with all of your existing hardware. It won't be as durable, though. The rubber cushions on my original-owner 1969 wore out VERY quickly; I recall it very well.

[Joe L.]

Re: 69 Seat Adjuster

The seat adjusters on my 69 coupe don't seem to match the assembly manual or vendor catalogs. I'm the original owner, so I know these came on the car. See the attached image for what mine look like.

My question is: Should there be a rubber "cushion" on this part? I'm almost certain remember seeing the rubber tearing off as it aged. This part screws into the lower edge of the seat back and rests on a rubber bumper on the bottom of the seat when in the sitting position. Next question: If there should be a rubber cushion, where might I purchase a couple?

Thanks,
Mike

Mike------


Here are some photos of a GM #400765. This will replace your original piece and you would re-use the flange nut and washer. It will appear very similar to the original when installed. You may have to shorten the threaded length.




DSCN2864.jpgDSCN2866.jpgDSCN2865.jpgDSCN2867.jpg


I think you must have a later 1969. I believe that early 1969 used a different sort of bumper on the seat back. This was a rubber bumper with a phillips head SCREW retaining it to the seat back, just like 1968. Later 1969 went to the 1970 style set-up which used the GM #3901496 assembly. The 3901496 was replaced for SERVICE by the 400765 in July, 1972.

By the way, GM says that the 400765 is also the SERVICE bumper for 1968-76 hoods. However, I don't see how this would work with original 68-76 lower hood latches. The hood latches accept 1/4-20 thread for the bumper/bolt assembly. The 400765 is 5/16-18 thread. In addition, the 400765 is configured somewhat differently than the original 68+ bumpers. If the lower hood latches were re-drilled and tapped for 5/16-18, the 400765 would work, though.

[Michael C.]

Re: 69 Seat Adjuster

Joe,
Mine was built in Sept 69. The attached photo shows the hood bolt/bumper (1/4-20) and the upper seat bolt - missing bumper (5/16-18). While the 400765 will be functional, it won't be correct. But this won't be the only "flaw" with this car, so I guess I'll live with the 400765.

Thanks for the info.
BumperBolts.jpg

[Joe L.]

Re: 69 Seat Adjuster

Joe,
Mine was built in Sept 69. The attached photo shows the hood bolt/bumper (1/4-20) and the upper seat bolt - missing bumper (5/16-18). While the 400765 will be functional, it won't be correct. But this won't be the only "flaw" with this car, so I guess I'll live with the 400765.

Thanks for the info.
[ATTACH=CONFIG]46923[/ATTACH]

Michael-----

My original owner 1969 was also built in September, 1969. It has the same parts you have pictured.

I'm not so sure that the 400765 will not appear correct. Checking into this more, I am now convinced that the original GM #3901496 was a bonded assembly and not a separate stem and bumper sort of thing. My recollection of it being separate pieces may be based on AFTER the wear-and-tear caused the bumper to dislodge from the stem. Consequently, I think that the only difference between the 3901496 and 400765 may be the length of the threaded stem. This can, of course, be easily shortened, So, once installed, I really don't think there would be much, if any, difference between the original and the 400765.

[Graeme B.]

Re: 69 Seat Adjuster

If it was bonded Joe, why would it have the cross-recess in it for adjustment? Cheers, Graeme.

[Joe L.]

Re: 69 Seat Adjuster

If it was bonded Joe, why would it have the cross-recess in it for adjustment? Cheers, Graeme.

Graeme------


The 400765 has a cross-recess just like the original 3901496. It may not be clear in my photos but it's there. This feature on the 400765 is just like the originals.