Dot bolts - IH bolts - years?

[inairam]

What years were dot bolts used and IH bolts used? What happened after IH bolts - just off the shelf bolts?

[Glen]

Hi,
The bolts with a dot on the heads were used for the first few years of Cubs.
By 1955 they had changed to modern markings, with a dot in the center of the head, and 3, or 6 lines.
My 1956 Cub has mostly bolts with the IH on the heads, and 3 or 6 lines.
In the 1970's, they used bolts with WP on the heads. I remember seeing them at the dealer.
I don't know the exact years when they changed from one to another.

Below is the torque table from the Cub service manual, GSS-1411, from 1976, showing the bolt heads in the lower right of the page.
At the bottom of the page it gives some info about the bolts.

http://www.farmallcub.info/manuals/gss- ... 000-06.jpg

[Daniel H.]

IH made ther own bolts. I believe the WP was West Pulman works. I think the production methods changed when they went from the dot head bolts to the modern 3 or 6 lines.

[Glen]

Hi,
Your info says you own Cubs from different years, you could look at them to see if they have bolts with the different markings on the heads through the years.

Below is a pic from TM Tractor of a transmission shift fork with an IH bolt in it.

[inairam]

My question is for restoration purposes. I have bolts and I have tractors I was just looking for a guide as to what goes where.

I pretty sure anything in the 40s is dot and anything in the 70s is wp. It is the IH bolts - when did IH start and when did they end is the question.

I have not noticed anything in the parts books saying "up to sn xxxxxx" or "after sn xxxxxx" use this bolt. How did IH control/introduce the different bolts? There must be something documenting it from IH.

[Stanton]

In answer to your question, I don't think there's a comprehensive "guide" showing the breakdown in years when each type of bolt was used. There would be no reason for IH to produce such a guide. I do think they mentioned changes or revisions along the way. Here's some info on bolts I just found on the Wisconsin Historical Society's website of the McCormick Collection (located here: https://www.wisconsinhistory.org/Records/Article/CS15303).

I did a Browse search for "bolts" and there were 21 pages with over 400 results. Here's some of interest:

A 1951 article in a periodical mentions the WP bolts:

Then a portion of an internal directive letter from IH about the "IH" Trademark dated November 1, 1962:

So, we know that by November 1, 1962, all bolts were to have the "IH" stamped on them. That doesn't mean they all magically started using the new "IH" bolts on that date; old stores of "WP" bolts would have to be used up first. But this gives us a better time frame when the transition was made. Hope this helps. I didn't find any info on when the "WP" bolts replaced the "dot" bolts.

If you have some time, browse through the Wisconsin Historical Society's website and share what you find with us. Thanks.

[Jim Becker]

I don't think the trademark directive necessarily indicates the IH was physically on the bolt. It does mean that it was available for use in some aspect of marketing (which probably included the box the bolts came in).

The "WP" bolt marking came after the "IH" marking. All three head markings were produced at West Pullman at one time or another. Note the bolts in the 1951 picture were being produced at West Pullman and have dot heads.

[tomcough]

West Pullman suppled fasteners to General Motors. My grandfather owned a 1969 Chevy Biscayne. The machine screws holding down all the sheet metal in front of the engine bay had the IH logo.

[Gary Dotson]

I believe that's correct, Tom. My friend was looking for the correct bumper bracket bolts for his 67 Corvette, the restoration manual specified the WP head marking. They were available from a restoration supplier.