'55 2nd Series Temp Wiring

[Krumenauer]

I have installed a '54 261CI 6 and have a new Gauge Cluster in my '55 restoration. The new cluster has two terminals for the engine temp connection (electrical?) as opposed to the copper tube (Mechanical) fitting for the original cluster. What or where do I go to get a temp sending unit from the engine that will work with the new Gauge Cluster?

[Katrina/10]

You have a gauge for a 56. If you want to use that one, order a sender from the same people you got the cluster from.

[Krumenauer]

I purchased the gauge cluster from LMC. They do not list a sending unit for this gauge set. If this gauge cluster is for a '56, there should be an electronic sending unit for '56's, correct? Any other suggestions?

[Katrina/10]

I'm surprised LMC doesn't show a sending unit. Should be a very common item, try the local parts store.

[_Ogre]

if the gauge is a stock 56-59 truck gauge, gm had the same sender 56-78
may still be available at napa, autozone or oreilleys
classicparts.com/1956-72-Water-Temp-Sender

2 wires on the gauge, one is 12v+ and the other grounds thru the sender
similar to the stock fuel gauge

[Krumenauer]

Thanks for the help.

[gwsut]

As I see it, your problem is really in the head. IF your head has a fitting that only accepts a capillary tube, you will have to change the temperature gauge in the instrument cluster since the sender unit the others recommended won't fit into the head's water jacket.

[1project2many]

I once used a special adapter to install a 1/2" NPT sender in a head with a 3/8" NPT hole. As long as the sender touches coolant you will get a reading. I can't say where the adapter was originally sourced though... I have a big bucket of brass miscellaneous fittings that I paw through for jobs like this.

[Krumenauer]

Thanks for the additional info. I will first obtain the a sending unit and then begin the search for an adapter. Even with the adapter, the sending unit should make contact with the coolant in the head. I don't really have an option in changing the gauge in my new gauge cluster.

[_Ogre]

is the hole in a spot where it can be drilled out and tapped for 1/2'' npt?

[Krumenauer]

Yes. The hole is on the top of the head, left side near the rear of the engine. This would be a bit of a job but is a possibility.

[gwsut]

I like the adapter idea from 1project2many. I get nervous when I think about tapping cast iron especially when the end results might mean a useless head. In fact I like the adapter idea so much, I think I will try in on mine. Thanks.

[Valarius_Starchaser]

Eaton number 40183109 is what I used once if I remember correct and am reading this thread right just thread sealant everything and she worked great.

I have found them online at amazon Fleebay even some Oreillys and other local parts stores even Home depot/Hardware stores has an equivalent in my town

https://img2.fastenal.com/productima...038-131280.jpg

[ptc]

Originally Posted by gwsut

As I see it, your problem is really in the head. IF your head has a fitting that only accepts a capillary tube, you will have to change the temperature gauge in the instrument cluster since the sender unit the others recommended won't fit into the head's water jacket.

Originally Posted by Krumenauer

Yes. The hole is on the top of the head, left side near the rear of the engine. This would be a bit of a job but is a possibility.

Love this conversation.... if somebody less "motor-ish" was listening in they would probably think we were all talking about an insane asylum.... with "problems with heads" and "holes in our heads" ....

Carry on Guys!!!

[Krumenauer]

Thanks for all the help from everyone. I am on the trail of the adapter and the Temp. Sensor. As I continue to move forward with this restoration, I know that I will have additional '55 Chevy truck related questions.

[Katrina/10]

The hole in the head should be ordinary pipe thread.

[_Ogre]

Originally Posted by Katrina/10

The hole in the head should be ordinary pipe thread.

3/8'' npt for the capillary tube, 1/2'' npt for the temp sensor