Chad, testing the sender should be easy.
In the service manual there is a chart (table 1 on page 15-25)that list resistance values for certain temps.

The sender you say you have (pn S2335-1) should read 990 ohms at 72 deg F.
and 34 ohms at 250 deg F.
I would take these measurements with the temp guage disconnected.

Keep in mind that there are 5 different senders that were used on the 152s and they all have different resistances at
different temps.
Be sure you have the correct sender.

Ron Stewart
N5282B
KSFZ


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