Top Hat or High Hat screws on FI

[Larry M.]

I may have read every post on this and have these questions: can anyone say they have seen an original car with the pointed tip thread cutting style factory installed? What other variations have you seen on original cars?

Many things are said in the threads but I don't recall seeing the above addressed specifically.
1. Two low number guys posted pics and said that the blunt tip thread cutter was correct (maybe only correct) version. I assume they did see original cars.
2. There is much discussion of the variations (pointed, pointed with cut, blunt and blunt with cut), the drawing possibly allowing the variation, and different variations coming out of the same bin under the same part number. Most of this discussion if for pointed tips.
3. There is testimony of less than all four being high hat, often the bottom two which are harder to access.

I think it is implied that all variations were used on Corvettes but I didn't see this said directly.

My car, which I'm sure has been apart before, has only three screws: two blunt high hats without cut (circle and circle with radial marks head marks) on the top and a 5/16 indented hex "L" correct screw on the lower right. I have it apart right now to install a new radiator and would like this answer before I put it back. The high hats seem to cut a looser thread and will not hand thread in the bottom so I'm thinking they were never in the bottom and they may not even be original on the top. The 5/16 fits loosely on top and would likely strip with torque. But I've acquired a handful of pointed tip with cut and double anchor head marks. I could use the advice on whether to use them.

[Richard M.]

Re: Top Hat or High Hat screws on FI

Larry, What generation and what specific area of assembly are you referring to? I read your post twice but I am confused.

5/16 bolts? Are you asking about the fan shroud and the attach bolts to the radiator support? If so, I've not seen pointed tip 5/16" thread recessed head bolts there on C1's before, always blunt. C2's I don't remember.

edit....I see on your profile you have a '64 fuelie ? Is that the car in question ?

Rich

[Joe R.]

Re: Top Hat or High Hat screws on FI

I may have read every post on this and have these questions: can anyone say they have seen an original car with the pointed tip thread cutting style factory installed? What other variations have you seen on original cars?

Many things are said in the threads but I don't recall seeing the above addressed specifically.
1. Two low number guys posted pics and said that the blunt tip thread cutter was correct (maybe only correct) version. I assume they did see original cars.
2. There is much discussion of the variations (pointed, pointed with cut, blunt and blunt with cut), the drawing possibly allowing the variation, and different variations coming out of the same bin under the same part number. Most of this discussion if for pointed tips.
3. There is testimony of less than all four being high hat, often the bottom two which are harder to access.

I think it is implied that all variations were used on Corvettes but I didn't see this said directly.

My car, which I'm sure has been apart before, has only three screws: two blunt high hats without cut (circle and circle with radial marks head marks) on the top and a 5/16 indented hex "L" correct screw on the lower right. I have it apart right now to install a new radiator and would like this answer before I put it back. The high hats seem to cut a looser thread and will not hand thread in the bottom so I'm thinking they were never in the bottom and they may not even be original on the top. The 5/16 fits loosely on top and would likely strip with torque. But I've acquired a handful of pointed tip with cut and double anchor head marks. I could use the advice on whether to use them.

Larry,

I have four blunt tip with the cut that came from my 64 SN 14,XXX. Unfortunately they have been cad plated and did not have that finish. They are high hats and have the circle.
I have one blunt tip without the cut that is black phosphate finished.
You are welcome to either the four cad plated ones or the one black phosphate.
Your call.
A source for these screws is one is used on all 64-65's with the power vent as the cable is held by one.
Another source is the early 60's Corvairs as the heater blower motor uses these screws also.
JR

[Jerry B.]

Re: Top Hat or High Hat screws on FI

Could someone post a picture?

[Larry M.]

Re: Top Hat or High Hat screws on FI

I apologize for not giving the assembly reference. The high hat is a 1/4 head and the 5/16 refers to the head. They are both #8 (approx) sheet metal screws used to secure the air cleaner S tube to the radiator support. I've attached a picture which I previously downloaded. I'm guessing it was posted by Joe Ray.

Joe- do you think the four screws were original to your car - factory installed?

[Joe R.]

Re: Top Hat or High Hat screws on FI

Sure, here are the screws that I was referring to! As I said before the cad plated ones are correct configuration BUT originals were not cad plated!DSCN3575.jpg
JR

[Larry M.]

Re: Top Hat or High Hat screws on FI

Here is a pic John Hinckley posted of screws which came from the Corvair assembly line. They are like the ones I've acquired. My original posts asks if anyone has actually seen them in an original Corvette.

[Joe R.]

Re: Top Hat or High Hat screws on FI

I apologize for not giving the assembly reference. The high hat is a 1/4 head and the 5/16 refers to the head. They are both #8 (approx) sheet metal screws used to secure the air cleaner S tube to the radiator support. I've attached a picture which I previously downloaded. I'm guessing it was posted by Joe Ray.

Joe- do you think the four screws were original to your car - factory installed?

Larry,

Guess that was my pic from some time ago. Still had it on the puter! Yes those are the four screws from my 64 FI Roadster. Only problem is that they were accidentally cad plated when they should have been black phosphate like the screw in the center. They are the correct configuration, blunt tip, self starters and an "O" on top of the hat!

JR

PS. Most that I have seen from 64's and 65's have been forced into an already stamped hole in the radiator support and were crooked with the tip slanting down. The old union worker trick of hit the hole and drive the sucker home.

[John D.]

Re: Top Hat or High Hat screws on FI

Larry, Your pic right above my post has at least 1 screw that is Identical to Joe Ray's original.
From my past experience I would expect to see this type screw starting sometime in '64 and all of '65.
Now you see a lot of these type screws without the starting provision. The flattened area. Can't describe it.

Joe mentioned as others have forever that the Corvair is a good place to look for these screws. But the kicker is the Corvairs used two variations of these screws. One with just the spiral and one with the starting/flattened area like the pics. Go figure. Which one is correct for the Corvette? Well I look for the ones in Joe's pics myself.
John

[Larry M.]

Re: Top Hat or High Hat screws on FI

John - get your magnifier out. All five in Joe's pic have blunt(flat) tips, 4 with a cutting slot and 1 without. All four in John's pic have pointed ends, 1 with a cutting slot and 3 without, none which match Joe's.

But that aside I think you are saying that you have see both types in Joe's pic on original cars. Is that right?

Have you see either type in John's pic on an original car?

I have a Corvair source. I bought 10 like John's pic with the cutting slot. But I don't want to use them unless I can confirm they are correct.

[Richard M.]

Re: Top Hat or High Hat screws on FI

Holy crap I was off by a country mile....

But I'm learnin' alot.

Rich
p.s. but I guess I got the masses interested. I'll sit back and be learnin' now that I'm subscribed.

[Gary J.]

Re: Top Hat or High Hat screws on FI

I have also seen them holding the A/C ducts on on my 1966 Corvette.

[Rich P.]

Re: Top Hat or High Hat screws on FI

tn_IMG_0772.JPGtn_IMG_0773.JPGIMG_0774.jpgHere are a few pics of blunt and pointed tip. Most mid 64-up I have seen are pointed tip.

[Rich P.]

Re: Top Hat or High Hat screws on FI

tn_IMG_0775.JPGIMG_0776.jpgIMG_0777.jpg The one with L and the one with 3 lines are the blunt tip the rest are pointed tip.

[Larry M.]

Re: Top Hat or High Hat screws on FI

Rich - thank you. I acquired several of these and I put the pointed on my car. I have several extras including some blunt with a cutting slot which you do not show. I used the ones I did because they had matching "large anchor" head stamps. Most of mine have small double anchor and a few oddballs. Your pictures are great.