1934 Lasalle rumble seat

[zephyrdave]

The rumble seat back cushion fits with two tabs that go in grooves under steel plates at the top. How is the bottom of the rumble seat back attached? Any one know? Thanks Dave

[Str8-8-Dave]

I have been bucking for a subject matter expert rating for 1931 Buick 8-66S rumble coupe seat back- my car had nothing for rumble seating parts when I started.  I just completed a project to replicate the wood frame for the seat back spring that attaches the springs to the rumble lid.  In 1931 there were 2 S-bent tabs made of steel bar at the top of the seat frame that tucked under steel plates like your LaSalle and then had 2 more flat tabs at the bottom of the wood frame that had countersunk holes for flat head wood screws to attach the bottom of the seat back frame to the rumble lid woodwork.  As for the latches, many of these parts were used across GM carlines.  I found exact duplicate latches for rumble lid and golf door at The Filling Station which specializes in early Chevy/GMC parts.  The only obvious difference in the latches is the originals were chrome plated, and the ones I bought from The Filling Station are zinc plated.  Attached is a screen print from their online catalog showing they have quite a selection of early latches.  I would suggest calling them and sharing a picture if you have one and see if they can match it up.

 

 The Filling Station – Chevrolet & GMC Quality Reproduction Parts

 

Below are the attaching strap brackets I made up for my 31 Buick 8-86S rumble coupe.  These are copied from originals via pictures and measurements from my Buick pen-pal in Georgia...

 

The wavy brackets slide into the slots you mentioned in your post at the top.  The bottom a

attachments are straight straps with countersunk holes for #10 flat head wood screws, 2

attach each strap to the bottom of the wood seat frame, 1 more drilled from the other side

accepts a #10x1" flat head wood screw to attach the bottom of the seat assembly to the 

woodwork on the rumble lid.

 

Here are the slots in the top of my rumble lid.

 

This is the back of my new replica seat back frame.  Wavy brackets at top, flat straps at bottom.

 

The arrows show the bottom attachments spaced apart like the uppers.  The red painted wood cross member the seat back screws to is part of the rumble lid woodwork.

 

Pictures of my new seat back frame with springs attached test mounted on the rumble lid.

 

Next stop for seat base and back is the upholstery shop.

 

This is a screen shot from about page 5 or 6 of The Filling Station's parts catalog with listings for various rumble lid latches.

Edited December 13, 2021 by Str8-8-Dave
Arrange pictures, captions (see edit history)

[zephyrdave]

Dave, thank you so much. What an excellent reply, with pics also. Dave

[Str8-8-Dave]

13 hours ago, zephyrdave said:

Dave, thank you so much. What an excellent reply, with pics also. Dave

That's a really nice looking car.  Please update us as it progresses...

[edinmass]

1931 Cadillac V-8 is very similar.