Steering Column Shear Pins?

[Shakey]

I was looking at another topic regarding this however there is no explanation as to what they are, what they look like, how they get broken etc.....

Can someone explain:

what these shear pins are
what they do
what they look like
how to tell if they are any good
how they get broken
what happens if you don't fix them....

Please teach me!

Thanks

[Chryco Psycho]

the strring column has a section of the shaft with an inner & outer sleeve , there are nylon shear pins at a 90* angle across the shaft , if the shaft is hit the nylon pins will shear & the column can collapse , the column cannot disconnect & lose steering as the shaft is too long to come apart   

[Charger_Fan]

In the other thread, I thought you guys were talking about the pin (or pins) at the bottom of the steering column that slide into the coupler on top of the gearbox...the ones I've seen are definitely steel.

Are there different pins up further towards the steering wheel made of nylon?

[John_Kunkel]

The shear pins usually fail if someone drops the assembled column or raps too hard on the end of the shaft.

Mopar makes a kit to repair sheared pins but many just replace them with plastic screws or rivets.

[T16]

what happens if you don't fix them....

Also would like to know..

Got a steering shaft with broken pins.. thinking about drilling in som plastic pins but I dont know the correct lenght of the shaft.. since its collapsed

[Back N Black]

There is two small plastic pins, not sure of the diameter.Here is a couple of pics of a before and after .in the first pic its fully extended and in the second you can see it collapsed. Also you can see the holes where the plastic pins use to be.If you want more pics let me know.

[Chatt69chgr]

The Mopar collapsible steering column kit, pn 3514996 for 69-75 model years, has apparently been discontinued.  When I looked it up I got a No Parts Found return.

[T16]

From my ´72 service manual:

Plastic is injected through two small holes in the hollow piece into a pair of annular grooves on the solid portion of the shaft. The four small holes filled with plastic form the shear pins. Upon impact, the shear pins break off and the shaft gradually telescopes against a resistance provided by the plastic collars in the annular grooves

Soo if I understand this right.. there are no holes going through the inner shaft (lower).. just some small grooves 

Been searching for some holes or something on the inner shaft, but i´ve found nothing.

Plan is to find the annular grooves.. drill holes through the inner shaft, and insert some kind of plastic pins. In that way the shaft will get the correct lenght.