Topic: Gas Tank Screws

[ChrisV289]

Trying to determine which gas tank screws are correct.  According to the hardware excel sheet 31498-S8 and 42143-S8 are listed under gas tank body.  31498 has a diamond symbol in the middle while 42143 is plain.  Which was commonly used in SJ production?  I have a mixture of both right now but they are looking pretty sad....

[J_Speegle]

Guessing that your asking about fall 64 period at San Jose based on your other  threads.

Found the diamonds being used

Ignore finish - surface was rattle canned silver  by PO





Slightly later example = barely make the marks out due to the crud

[jwc66k]

Out here on the left coast, I'm about 4.5 miles from the San Jose plant, pretty much all we see are San Jose built cars so the hardware cans I have on the shelf would reflect what hardware San Jose cars used. Many of the cans are almost full. For 31498-S(x = not refinished), I have both the diamond head marking and some "D" heads. For 42143-S(x), about the same mix for head marking, a lot of diamond and maybe a 1/4 can of "D" heads. These are 28 ounce Mexican sauce cans to give to an idea about the amount. Plain head marked screws are generally what you get in replacement "kits", not factory. Looking at the spreadsheets, 14-10 and 14-14 flat tip sheet metal screws were not used until 1968. Can't say for Dearborn or Metuchen.
Jim

[Bob Gaines]

My 2 cents- 65-67 diamond shaped makers mark on the sheet metal screws in question predominantly used at SJ from my observations. 

[ChrisV289]

Thanks guys for the clarification.  I'll have to order them directly from AMK...I haven't taken the tank out yet to replace but what does that 1/2 inch bolt do?

[Bob Gaines]

Since the diamond screws were used extensively in the engine compartment too I used to order the gas tank kit all the time from AMK so I would have plenty. I told a friend to do this recently  and his gas tank kit when it came with just the plain no marking screws.

[carlite65]

Thanks guys for the clarification.  I'll have to order them directly from AMK...I haven't taken the tank out yet to replace but what does that 1/2 inch bolt do?

it's for the bumper guard bracket.

[J_Speegle]

it's for the bumper guard bracket.

+1 one of two on that side

[ChrisV289]

Just want to double check, the finish on these screws should be a phosphate finish (S2) and not a zinc finish (S8) correct?

[CharlesTurner]

Gas tank screws I have seen from that time period were zinc.

[Bob Gaines]

Gas tank screws I have seen from that time period were zinc.

+1

[ChrisV289]

Thanks guys! Going to order the zinc finish from AMK.  Slightly off topic but relevant, this type of screw, 31498 is also said to be used at the ground wires for the headlights near the battery on the radiator support. I looked at mine and it does have the diamond head but it is a little shorter than the tank screws.  Almost the size of the screws that hold the starter solenoid but without the "D" logo.  Is this a variation or a different screw number?

[CharlesTurner]

They are all different sizes, assembly manual should show the fastener number and then you can use the AMK guide to fasteners to get the length.

IIRC, the gas tank screws are about the longest of those type, only other I can think of that long are the splash shields.