"High Hat" FI "S" Tube Screws

[Chuck G.]

Anybody know where I can get four of 'em? Seems I recall reading that they were used in some window regulators, or some other door application.

Paragon used to have them, at least they were listed in their catalog. They're "NLA", no longer available. Thank you. Chuck

[Michael H.]

Re: "High Hat" FI "S" Tube Screws

Chuck,

The "high hat" 1/4" hex screws were used in several different locations on the inside portion of the heater assy on many GM passenger cars and are quite common, easy to find. What year is your car?

[Chuck G.]

Re: "High Hat" FI "S" Tube Screws

It's a 63, Mike. Chuck

[John H.]

Re: "High Hat" FI "S" Tube Screws

Chuck -

They were commonly used on passenger cars where the heater control cable "flags" attach to the heater box, and '65-'67 Corvairs had about 20 of them holding the bottom tunnel cover on, and another 20 or so attaching the side retainer strips in the engine compartment for the rubber seal between the engine and the body.

[Michael H.]

Re: "High Hat" FI "S" Tube Screws

Chuck,

If it's a 63 and you're restoring back to original, then you will need the early style 5/16" hex "L" head screws, not the tall 1/4" screws. Much more difficult to find.

[Mike M.]

Re: "High Hat" FI "S" Tube Screws

mike: mid year relays in vicinity of drivers courtesy lite, is source for the 63 s-tube to core support fasteners. mike

[Mike M.]

Re: "High Hat" FI "S" Tube Screws

mike: mid year relays in vicinity of drivers courtesy lite, is source for the 63 s-tube to core support fasteners. mike

[Michael H.]

Re: "High Hat" FI "S" Tube Screws

Mike,

That screw, if I remember correctly, was the same part number (226?) with the correct "L" head but often these are longer than the correct original "S" tube screws. Makes no sense if their the same number but I've removed a lot of them to compare. I don't remember the different sizes. Maybe someone has a few loose that they can measure?

[Chuck G.]

Re: "High Hat" FI "S" Tube Screws

Hi Mike. The new JG states: "........front of the S tube is attached to the core support with four black phosphate recessed hex head sheet metal screws installed at an obvious angle to the core support, not perpendicular, due to the tight proximity of the S tube to the core support. A known original headmark of this early type is "M".

After approximately 1963 Vin 9000, a black phosphate "hi hat" recessed hex head sheet metal screw is used."

No other info is given. I have a July car...19500'ish, so according to the JG, I need the hi hats. Chuck

[Mike M.]

Re: "High Hat" FI "S" Tube Screws

chuck et al: my 28k mile ZO6, which would easily bowtie if it hadn't been repainted in 1970, has the early L logo'd recessed hex head fastners. its vin 20301. i'd eave the L's on your car if i were you, chuck. call the augusta midget and run it by him.mike

[Michael H.]

Re: "High Hat" FI "S" Tube Screws

Chuck,

I agree with Mike. If you're restoring for accuracy, use the 5/16" "L" head screws but you may have to use the tall 1/4" screws for the NCRS judging.

[Mike M.]

Re: "High Hat" FI "S" Tube Screws

mike: i'm not sure but that the early 64's may have also used the L logo fastner. seem to recall an early car that we bowtie judged that certainly appeared to unmolested with the L logos. mike

[William C.]

Re: "High Hat" FI "S" Tube Screws

I know of at least one '64 in relatively unmolested condition with the short screws in the 6000 s/n range.

[Michael H.]

Re: "High Hat" FI "S" Tube Screws

Yep, my 4000 mile unrestored 64 had the original "L" heads in it. VIN was 5xxx. It wasn't long after that VIN that the tall 1/4" went into service. The AIM never listed the change to the tall screw. It was an "on the line" decision, not from engineering.

[Mike M.]

Re: "High Hat" FI "S" Tube Screws

i can understand why the decision to change to tall hat was made by the guys on the assembly line. the tall hat fastners sure do install easier than the L logo if ya got an air wrench in hand. mike