Rochester Quadrajet bolt hole size

[forestb]

Does anyone know the size of the bolt that will fit in these holes? I tried the bolts that I have and none of them fit.

[Getter-Done]

What's the number on your carb?
The older carbs I think that was #10 x 32 threads?
I can check tommorrow.

If it a late model it has metric threads.









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[Troy Sr]

Well I went out and grabbed the screw that goes in those holes and it's 12-28 UNF. They are c'sunk oval head screws. I even took a pic of the screw but I can't get it to upload.

[forestb]

17080507
2801 DNR

What is UNF?
Don’t worry about the photos

[forestb]

Thank you guys

[Getter-Done]

17080507

170 means 1976 and later.
4th digit (8) means {in the 80's}
5th digit means (0) 1980
6th digit is Califorina only
7th digit is Chevrolet
8th digit is an odd number example (1,3,5,7,9) so it's a manuel trans.

Link: https://www.chevyhardcore.com/tech-s...ication-guide/


(UNF stands for Unified Fine Thread)

Link to threads : https://journeymans-workshop.uk/unified.php












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[forestb]

So does 1976 and later mean it is a late model? So does that mean it is metric?

[Getter-Done]

I don't know for sure.
Your's looks like it would be standard screws.
The ones that are metric have those torxs screws ,
But I would check the other screws with a thread pitch gage.
Or with a standard screw just to be sure.






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