Water Pump Back Plate Bolts, SBC

[69-er]

Did these 1/4-20 bolts have a specific marking on the head when originally assembled at the factory? I have two 3953692 pumps and both have a mixture of different head markings.  All are the real close in their design/shape with captured tooth washers.  They have been rebuilt in past so who knows which are correct.

I see in the research topic that the pics shown their the bolts appear to be all different too.

[69-er]

...

[Mike S]

 I rebuilt my original 67 L35 water pump (it still has the cast iron impeller http://www.camaros.org/forum/index.php?topic=16405.msg148436#msg148436) and did take pictures. This morning I opened one and see a clear shot of the bolts and copied them into this attached image. One looks like a reverse letter 'P'. The other two are clear.
 Being multiple suppliers were sourced by GM it is understandable to see different head markings of an otherwise same size bolt.

Mike

[bertfam]

Did these 1/4-20 bolts have a specific marking on the head when originally assembled at the factory?

No, as Mike stated, there were multiple suppliers to fasteners, so you'll see all kinds of markings.

Ed

[69-er]

My reasoning that it was odd to see different markings is that I figured at any given time there would be one style of bolt available in the bin to grab.  When the bin was replenished with a new and different batch then some of the pumps next in line would have mixed hardware.  Just my theory...

But, again, I don't think mine applies to this theory since mine are rebuilts.  I would imagine they use all new hardware.

Bottom line, I guess I don't have to worry about this.

[Mike S]

 I believe it was John Z who said the bins were refilled well before they were empty. So, I image that after years of mixing vendor supplied hardware that it is possible to have a good variety on a pump.

Mike

[69-er]

Makes sense now.

Thanks for all your input.

[169INDY]

69-er:
Most likely some of those fasteners are Rebuilder installed I offer this base  on.
Take the squiggly flag symbol,,,,,head
It is registered to: Asia Fastening (US) Inc. 1304 Kerr Drive Decorah IA 52101 Delaware Corporation Registration Number: 0874555

Link to my reference
https://www.uspto.gov/sites/default/files/trademarks/law/fastener/FQA_Registry.pdf

see page # 44.

Folks around here did some research on fastener head marking and cross referencing to registered manufactures. Guys around here are in the Supply chain and can speak to this, My experience is Such that when we were working on submarines occasionally fed stock system hardware become contaminated with product(s) not meeting the physical and composition requirements and hardware must be identifiable such that products can bee screened and positively  identified for defect and rejection thus the fastener marking requirements.

to bad we do not have the registration for the years in the past?

anyway Hope this was helpful, just keep the correct style and be done with it?  or harvest from other vintage sources, since we tend to want to stay away from Ace hardware for our restoration needs here.

JIM

[69-er]

...or harvest from other vintage sources, since we tend to want to stay away from Ace hardware for our restoration needs here.

JIM

Exactly!

[68camaroz28]

https://www.camaros.net/forums/34-restoration-corner/466801-water-pump-back-plate-bolts.html