Solution to use 1/2 npt temp sensor with vortec heads

[70LonghornCST]

I had the same problem a while back. (LINK TO MY POST) I, like you, was contemplating using an adapter, but was convinced otherwise. I also tried using a sending unit that fit into my newer model head port, but the OHMs were not correct, and I got a faulty reading. Member Brian Mac turned one down for me, and it worked perfectly. That's the route I'd suggest.
Richard

[B. W.]

X2 on Brian Mac, he turned one down for me, pleasure to deal with.
(machined one on the left)

[randy.powell]

Brian Mac turned one down for me also. I spent way too much time and money trying to re-engineer different mounting locations, using different temp sensors that would physically fit but not read correctly due to different ohm ratings etc.

Save yourself at lot of time and grief - have a stock unit turned down from 1/2
NPT to 3/8 NPT.

There are numerous posts spanning back years on this topic. One member even ran the stock temp sensor through the operating range and recorded the resistance measurements at various temp.

My 2 cents worth...
B/R,
RP

[Big Kev-O]

From my experience if you do not have an original GM sensor and you are using an auto parts store replacement it will not read correct no matter where you place it because the resistance provided at running temp never puts the gauge straight up. The replacements available today are all off. So I just put mine in my Edlebrock intake and called it good. My gauge reads a bit cool when the coolant is 195* but I understand why and thats all that matters. If my truck overheats the gauge will tell me. I dont care if my gauge is 2mm on the cool side when it is warmed up.

[garyd1961]

Originally Posted by Big Kev-O

From my experience if you do not have an original GM sensor and you are using an auto parts store replacement it will not read correct no matter where you place it because the resistance provided at running temp never puts the gauge straight up. The replacements available today are all off. So I just put mine in my Edlebrock intake and called it good. My gauge reads a bit cool when the coolant is 195* but I understand why and thats all that matters. If my truck overheats the gauge will tell me. I dont care if my gauge is 2mm on the cool side when it is warmed up.

I'm not saying they aren't suppose to but I have been around these trucks since they were new and I never remember seeing one run with the gauge straight up.

[FirstOwner69]

If anyone is looking for an accurate new replacement sending unit to have Brian Mac turn down, here's a possibility from Lectric Limited. They claim it has the correct resistance and will provide accurate gauge readings. I can't vouch for that, but Lectric Limited has been serving anal Corvette restorers for at least 25 years.

https://www.lectriclimited.com/tempe...ing-unit-87597

[brian mac]

I am still around,mostly just looking and not posting. I check my pm box regularly. The senders I use are made by standard motor products from my local parts stores. I have done many of these with no complaints. Cost is $35, money order only and that includes a new sender and shipping. Here is my info:Brian McCullough
113 Red Oak Lane
Eufaula, Al. 36027

I apologize to the member that sent me a Letter and got no response. That is not like me and I will make it right. Pm me your mailing info and I will send you a modified temp sender at no charge.

[B. W.]

Brian, that is a stand-up offer. You & others like you are what make this forum great!

[Warrens69GMC]

Awesome Brian!

[MikeyMan]

Subscribed.

I may go ahead and buy one for "future considerations"
Was following several threads about temp senders awhile ago, and know how tough it is to get accurate readings on our original gauges.

Thanks Brian!

[D.PASSMORE]

Originally Posted by brian mac

I am still around,mostly just looking and not posting. I check my pm box regularly. The senders I use are made by standard motor products from my local parts stores. I have done many of these with no complaints. Cost is $35, money order only and that includes a new sender and shipping. Here is my info:Brian McCullough
113 Red Oak Lane
Eufaula, Al. 36027

I apologize to the member that sent me a Letter and got no response. That is not like me and I will make it right. Pm me your mailing info and I will send you a modified temp sender at no charge.

Brian, set you a PM, I need two modified.

TTT

[toolboxchev]

Originally Posted by B. W.

Brian, that is a stand-up offer. You & others like you are what make this forum great!

Wow, this site never ceases to amaze me, Another good guy to make this place shine.

Thank you for being a bright spot Brian!

[TCCGRIZ]

Subscribed

[lutronjim]

I don't understand the thread size. I have a LC9 engine and its sensor is metric. Each head is symmetrical. The driver side has a sensor for the computer. The passenger side is plugged. I just wanted one for the idiot light and haven't come up with one.

[dmjlambert]

If you know year and model vehicle that engine was made for, you can probably have an auto parts store look up the sensor part number. Or perhaps the sensor part number is stamped on the computer sensor. Find out the equivalent Wells part number. On the Wells website (https://gotech.com/parts/engine-cool...tch/wve/1T1101) you can look at the technical specs (sales drawings) for the sensor and see if it is an on-off sensor or different resistance at different temperatures, and you can also see the thread size and type. This is an example for the idiot light sensor for my truck with a 350 engine: https://cdn.gotech.parts/sales-drawings/TU78.pdf

So anyway, once you find the Wells sensor part number for that existing computer sensor, email Wells tech support and tell them you want a sensor that fits in the same threaded hole as your computer sensor, but need one that switches on at 240 to 250 degrees so you can rig a warning light on the dash of your old truck. They will probably write you back and tell you what Wells sensor to get. Then just run up to the parts store and get one.

It takes some annoying amount of research to do the idiot light, this is the thread covering the research for my engine, with some technical info: http://67-72chevytrucks.com/vboard/s...d.php?t=726025

Please post back here if your search is successful and let us know the technical info on what you found out, so we can all know.

[truckster]

Originally Posted by A1971Blazer

If you're interested, I could turn and thread some for 3/8"-NPT.....the only issue would be having to ship them to you......if you have a part#, I could buy them here, modify and ship to you.....I'm in East Tennessee.....I have 2 CNC lathes in my shop....I cut pipe threads all the time for one of my customers.........PM me.....

Whit turned one down for me. It's first-class work and he's a very nice guy.

[Lil Lucy]

Hi all- I know this thread is “ancient” in today’s fast-paced online world but I have been struggling to find a solution for this exact issue. I have sent a PM to BrianMac but no reply. I just saw that A1971Blazer had the ability to turn down and rethread this sensor as well so I will reach out to him but wondering if anyone has happened upon a sensor that will fit this application in the last few years.

BTW, I am doing a frame off resto on a 1967 C10 and literally visit this board 100 times a day. It is amazing how awesome everyone is and so willing to help. Thank you!

[74baggedbug]

Originally Posted by Lil Lucy

Hi all- I know this thread is “ancient” in today’s fast-paced online world but I have been struggling to find a solution for this exact issue. I have sent a PM to BrianMac but no reply. I just saw that A1971Blazer had the ability to turn down and rethread this sensor as well so I will reach out to him but wondering if anyone has happened upon a sensor that will fit this application in the last few years.

BTW, I am doing a frame off resto on a 1967 C10 and literally visit this board 100 times a day. It is amazing how awesome everyone is and so willing to help. Thank you!

I never found a direct replacement.. had to have a Senor turned down

[FirstOwner69]

BrianMac was last on here on May 31. So, he must be checking in periodically. You may want to send another PM.

[Lil Lucy]

Originally Posted by 74baggedbug

I never found a direct replacement.. had to have a Senor turned down

Thank you.

Originally Posted by FirstOwner69

BrianMac was last on here on May 31. So, he must be checking in periodically. You may want to send another PM.

Ha! That’s when I sent the PM, I must have just missed him. I’ll give him a day or so to see if he replies. Thank you.

[A1971Blazer]

Originally Posted by Lil Lucy

Thank you.


Ha! That’s when I sent the PM, I must have just missed him. I’ll give him a day or so to see if he replies. Thank you.

Replied to your PM...I can hook you up....

[jaros44sr]

Thanks for doing mine

[tdangle]

Originally Posted by Lil Lucy

Hi all- I know this thread is “ancient” in today’s fast-paced online world but I have been struggling to find a solution for this exact issue. I have sent a PM to BrianMac but no reply. I just saw that A1971Blazer had the ability to turn down and rethread this sensor as well so I will reach out to him but wondering if anyone has happened upon a sensor that will fit this application in the last few years.

BTW, I am doing a frame off resto on a 1967 C10 and literally visit this board 100 times a day. It is amazing how awesome everyone is and so willing to help. Thank you!

I got one from A1971Blazer and it works perfect.

[A1971Blazer]

Dana
going out to you today...thank you...best of luck with it
welcome to the site....post up some pictures of your truck...

[Lil Lucy]

Sensor requested on Friday and already have it installed today (Tuesday)! Fit perfect, thank you A1971Blazer! Here are a few pics of Lucy but she’s a little camera shy. Not quite ready for the runway yet...