NOS 1513321 Temp. Gauge Sending Unit - May 1956 vintage?

[David L.]

Early last month I bought a NOS 1513321 temperature gauge sending unit at a swap meet in Connecticut. It came in a blue AC box. The date on the flap of the box is "556-ACE-6" which I believe is May 1956. According to my 1957 Chev. Parts Catalog the 1513321 was not used until the 1957 model year. GM # 1513321 was discontinued in Nov. 1970 and replaced with GM # 546702 which was then replaced with the resurrected GM # 1513321 about 1978 or so.

The sending unit has a 5/16" diameter "dimple" on the bottom and is stamped "MADE IN U.S.A. 12V" upside down just below the hex (for 15/16" wrench).

Back in the 1980's I collected many used 1513321 sending units from various 1958-1961 Chevrolets in salvage yards which also have this "dimple" but the stampings were different and are as follows:

" AC - MADE IN U.S.A. - 12 VOLT " (upside down)
" . AC - MADE IN U.S.A. - 12 VOLT " (upside down)
" .. AC - MADE IN U.S.A. - 12 V ... "
" ... AC - MADE IN U.S.A. - 12 V ... "
" AC - MADE IN U.S.A. - 12 VOLT - B" (upside down, strange looking letter "B")
" AC - MADE IN U.S.A. - 12 VOLT - B " (strange looking "B")

Does anyone know the meaning of the "dots" or the strange looking letter "B"?

The original 1513321 sending units that I collected from 1963-1967 Chevrolet models generally do not have the "dimple". These units also have a 5-pointed star as well as the "dots".

Dave

[John H.]

Re: NOS 1513321 Temp. Gauge Sending Unit - May 1956 vintage?

Dave -

I have the original #1513321 sending unit from one of my 57's (unit failed in 1997), and it's the same as the fourth one down in your list - "... AC - MADE IN U.S.A. - 12V ...", right-side-up. It has the dimple in the bottom, no other stampings.

[David L.]

Re: NOS 1513321 Temp. Gauge Sending Unit - May 1956 vintage?

Dave -

I have the original #1513321 sending unit from one of my 57's (unit failed in 1997), and it's the same as the fourth one down in your list - "... AC - MADE IN U.S.A. - 12V ...", right-side-up. It has the dimple in the bottom, no other stampings.

John,

The senders with the stamping " ... AC - MADE IN U.S.A. - 12 V ... " w/"dimple" that I have came from the following vehicles:

1959 Chev 283 "T520D" (May 20, 1959)
1961 Chev 283 "T0403DB" (May 3, 1961)
1961 Chev 283 "T0713D" (July 13, 1961)
1961 Chev. 6 cyl.
1961 Chev. 6 cyl.
1963 Chev. truck 6 cyl.

I assume that they all work. They came from salvage yard cars many years ago.

Dave