67 Spare Tire Tub Bolts and Washers

[Gary S.]

A prior thread asked about the 4 screws and washers to mount a 67 tire tub. I have some good pictures that might help. The one is of a 14K mile 67 435 five Bowtie car before it was cleaned up for judging...note washer is separate item and plated.

I also show two sets of original tub mounting bolts and washers from 67 cars I personally know, worked on and believe to be original. Note the two different threads...course and fine as well as a different length. Anyone noted this before?

As for bolt head logo's, I have seen E, D, RBW, L etc. I think "D" is the only thing you will get when you order from LICS. It is not uncommon to have a mixture of head logo's as shown in the last picture of an "E" and "RBW" from my original 67.

The last picture I threw in to show measurements. This too is from my very original 67 coupe #1866.

TireTubBolt.JPGTireTubBoltsOrigDiffSizes.JPGHeads.JPGLength.JPG

[Scott S.]

Re: 67 Spare Tire Tub Bolts and Washers

Gary,

Thanks for posting this, there are a few threads discussing the GM 9420825 indented hex Screw used to attach the tire tub to the frame.

The GM 9420825 screws (same p/n called out for the tire tub, brake and fuel lines) from the '67 I'm working on are all the same. All are blank headmark (which other TDB Threads say is common), indented hex, no grade marks, 1/2" ATF and measure 5/16-24 x 1/2". The older P&A catalogs say GM 9420825 should be 5/16-18 x 9/16". It appears that you have original examples of both.

If I understand correctly, all of the frames were made in one place. Hard to imagine they used tooling to create 5/16-18 threaded holes on some frames and used different tooling to create 5/16-24 threaded holes on others, so what's the explanation?

[Timothy B.]

Re: 67 Spare Tire Tub Bolts and Washers

Scott,

I don't think the holes were tapped for either fine or course thread bolts. These bolts are thread cutters as can be seen in the way the tip is smaller and the little space at the tip.

I have never seen bolts at this location that are course thread like Gary states but I would not be surprised, maybe the fine threads stripped and the course threads held..

[Scott S.]

Re: 67 Spare Tire Tub Bolts and Washers

Scott,

I don't think the holes were tapped for either fine or course thread bolts. These bolts are thread cutters as can be seen in the way the tip is smaller and the little space at the tip.

I have never seen bolts at this location that are course thread like Gary states but I would not be surprised, maybe the fine threads stripped and the course threads held..

Thanks Tim,

I forgot these are "tapping" screws... back to the drawing board

[Philip C.]

Re: 67 Spare Tire Tub Bolts and Washers

Hi Gary by chance could you show a photo of the rivets that hold the "V" bar bracket to the cover lid, thanks Phil 8063