Temp Sending Unit Markings

[Al R.]

Was wondering, what are the correct markings on the temp sending unit for a 67 327-300Hp engine. Also, should the lettering be right side up when looking at it installed or upside down when installed? I've tried searching and cannot come up with an answer. TIA

[Larry M.]

Re: Temp Sending Unit Markings

Was wondering, what are the correct markings on the temp sending unit for a 67 327-300Hp engine. Also, should the lettering be right side up when looking at it installed or upside down when installed? I've tried searching and cannot come up with an answer. TIA

Al:

I believe that the stamping is "AC" and "Made in the USA" and "12v"......but I could be wrong on this without checking my sender. But this is close, if not correct.

The stamping is generally upside down when installed in the intake manifold, but John H and others have reported that this lettering could also be "right side up" when installed. I have not personally seen this.

The best thing to do is to check one before installing, using a test set-up. The archives have these temperature vs resistance charts. If you can't find them, let me know and I will repost.

If you are just looking for a correct sending unit, Wells makes one that works correctly for most folks.

Larry

[Jack H.]

Re: Temp Sending Unit Markings

The textual description given in NCRS Judging Guide books is sort of like a random number generator over the various years of car we judge that used the same physical part with two prime variables:

(1) Whether the stamped font is upright or inverted
(2) Whether the suffix reads '12V' or '12 Volt'

Having pulled perhaps 200 of these temp senders from various GM passenger cars and trucks from the era, I've seen all four combinations. My gut tells me there was more than one AC assy point and probably more than one set of tooling for the part. But, good luck trying to convince an NCRS judges of that once he's read the description in the Judging Guide and 'gotten religion'...

[Joe R.]

Re: Temp Sending Unit Markings

The textual description given in NCRS Judging Guide books is sort of like a random number generator over the various years of car we judge that used the same physical part with two prime variables:

(1) Whether the stamped font is upright or inverted
(2) Whether the suffix reads '12V' or '12 Volt'

Having pulled perhaps 200 of these temp senders from various GM passenger cars and trucks from the era, I've seen all four combinations. My gut tells me there was more than one AC assy point and probably more than one set of tooling for the part. But, good luck trying to convince an NCRS judges of that once he's read the description in the Judging Guide and 'gotten religion'...

Amen to that John!

JR

[Al R.]

Re: Temp Sending Unit Markings

Thanks guys, I've got 2 - 1 is ...MADE IN U.S.A. 12 V and is lightly stamped into the unit. when installed, it would be inverted, the other is ...AC MADE IN U.S.A. 12V... and is more heavily stamped than the first one and would be read right side up. Just unsure which would be correct. Al

[John H.]

Re: Temp Sending Unit Markings

Thanks guys, I've got 2 - 1 is ...MADE IN U.S.A. 12 V and is lightly stamped into the unit. when installed, it would be inverted, the other is ...AC MADE IN U.S.A. 12V... and is more heavily stamped than the first one and would be read right side up. Just unsure which would be correct. Al

Al -

It should make no difference to an experienced judge; that 1513321 sending unit was produced in all four configurations.

[Jack H.]

Re: Temp Sending Unit Markings

"...should make no difference to an experienced judge..."

Amen, John. But, that's NOT how the game afoot is being played on the judging field today. Some of the more experienced judges are hard/firm about there being only ONE correct configuration for this/that model year Corvette and the less experienced go by what's specifically stated in the JG book's descriptive text.

If you pull the part drawing, it specifically calls for the emboss to be "AC Made in USA 12 Volt". But, you'll run into the 'good ole boy' judge who swears the use of 'Volt' vs. '12V' indicates a REPRO part!

Many won't even bother to substitute 'service replacement' for 'REPRO' in their deduction descriptions. And, since only the owner sees/retains the original Flight Score Sheets (we aren't doing management reviews), we can conduct schools teaching political correctness until the cows come home. But, it just doesn't sink in with these set in their way judges.

Back to Al Rains' original thread. If you actually have two different senders and you want to know which (if either) will have a better chance of judging on your car without deduction, then go crack a book. Read exactly what the descriptive text says in the Judging Guide for your year car and fly with that. That will eliminate judgement call errors by the junior judges who tend to rely closely on what's been published...