Looking for two-pronged temp sensor for '71 Chrysler and alternate location.

[Rubatoguy]

My '71 300 had an aftermarket gauge kit put in using the original temperature sensor hole. The wires for the original sensor were left unconnected.
I would like to bring them back to functionality, because I want the gauge and the lights!
Does anyone know the part number for the correct sensor to use? It runs the 'cold' and 'hot' warning lights.
Also, is there an alternate location to plug the sensor into? I thought I saw somewhere that there was a port on the head you could use for a temperature sensor - but I might have imagined that.

thanks to all the help from everyone!

Todd

 

[Big_John]

There is another location for a temperature sender and it's for a factory gauge sender. Here's your problem. The size is small as the sender itself is smaller in diameter than the mechanical Bourdon tube that I can see in your picture.

The two prong sender for the stock cold/hot lights is also larger diameter and needs to mount in the hole the Bourdon tube is in now. The solution is to get rid of the mechanical gauge and use an electric gauge with a small sender instead. A good electric gauge is just as good and you don't have the headache of dealing with the Bourdon tube.

The sender you need should be available from any good parts store or Rock Auto. If you really want an NOS gauge sender and want the Chrysler part number, download a parts manual from MyMopar and then you can look it up. You'll pay more for an NOS and it's not going to be any better.

Here's a pic showing the other port. This is used in cars with temperature gauges and should be in yours too with a pipe plug in it.

 

[CBODY67]

The hot and cold lights went back to 1965 model year with 1973 being the last. Availability should be no issue for a "Chrysler" application.

Now that you know the temps the car runs at, consistently, in various conditions, the existing gauge's value is diminished. I DO concur on getting an electric gauge!

When Chrysler went to the gauge w/LED warning light in about 1975, it was masterful! Seems to use a contact on the gauge needle to trigger the light, as the needle goes past where the light triggers, the LED goes out, by observation.

Happy 4th of July!
CBODY67

 

[bigmoparjeff]

Rock Auto has a closeout on the correct switch right now:

More Information for FAMOUS BRAND WTA1137

There's two ways to accomplish your goal.

1. If it's small enough, move the gauge sender to the small factory hole that Big John pointed out, or find a small diameter sender that will work with the gauge.

2. Get an in-line fitting for one of the senders that can be installed in the heater hose going to the heater core. This won't be as accurate as choice #1, since the heater hose temp will be a bit lower than actual engine temp.


There are lots of gauge senders available on ebay for boat gauges under the Sierra brand. Teleflex was also a big gauge manufacturer for boats and it's not too hard to find the specs for the senders.


Also, once Rock Auto runs out of these senders, Chrysler used the same cold/hot temp switch as GM did on many of it's early to mid sixties cars. There are plenty of NOS GM switches on ebay.


Jeff

 

[CBODY67]

Finding the GM "cross-over" sensors will require some homework by the buyer! Which can come from the RockAuto catalog when you click on the particular part number of the sensor. Those listings also list other brands the part might fit IF there are some.

IF you might find a good NOS GM switch, give the seller the GM part number or aftermarket brand part number. DO NOT tell them it is not for a non-GM vehicle!!! They can only verify what is in their catalogs, so if yuou ask if it might fit a Chrysler, they'll probably say "No". Just BEST to not get to that point, by observation.

Enjoy!
CBODY67