Temp sending unit - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Handmedown · 12-17-2011, 10:29 PM

I have a 72 350. It has temp sending unit on both sides. I know one is for tcs and one for temp gauge. Driver side has one little post and pass side has one blade. Question is which one is which, I want to plug tcs side. Thanks

REEDS 72 · 12-18-2011, 09:39 AM

What is tcs becouse my 72 BB 402 is the same way.

Sport/Truck · 12-18-2011, 11:31 AM

You want the one on the driver's side (single post).

Sport/Truck · 12-18-2011, 11:33 AM

Quote:

Originally Posted by REEDS 72

What is tcs becouse my 72 BB 402 is the same way.

TCS= Transmission Controlled Spark IIRC.

Legolas894 · 12-18-2011, 11:36 AM

I think what he's saying that one is for the temperature switch (for TEMP light) and the other is the temperature sender for the temp gauge.

I think the probe with the post/terminal is for the sender (to the gauge) and the probe with the blade is for the switch (dash light).

LMC truck has a good picture in their 67-72 catalog (pg 155).

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=155

Sport/Truck · 12-18-2011, 11:44 AM

^ both with and w/o gages go on the drivers side.

Sport/Truck · 12-18-2011, 11:53 AM

Here's a wiring diagram but it don't show the TCS system.
http://www.boomspeed.com/bofh1968/ch...ng_diagram.pdf

FLcustom10 · 12-18-2011, 12:30 PM

Different years have different options. The 1972 has both a temperature gauge and a temperature warning light.

The drivers side is the single post for the Temperature gauge. The passenger side is the single blade for the Temperature warning light.

Do not buy these sending units at a local parts store. They will be wrong. Buy them from someone that specializes in these trucks like:

http://www.classicheartbeat.com/electrical_p-4.htm

Here is a link for information on the TCS. (Transmission Controlled Spark).
I don't believe that's what you are asking about. You'll have to click it again to make the diagram enlarge.

http://img232.imageshack.us/img232/1226/tcs14bb.jpg

Below are pictures showing the Temperature sending units, the gauge and the light. The Temperature warning light is on the far right passenger side. I use that to remember that the temperature sending unit for the light (single blade) goes on the same side.
You can't tell from the picture, but the light reads TEMP.

Sport/Truck · 12-18-2011, 12:52 PM

Quote:

Originally Posted by FLcustom10

Different years have different options. The 1972 has both a temperature gauge and a temperature warning light.

The drivers side is the single post for the Temperature gauge. The passenger side is the single blade for the Temperature warning light.

Do not buy these sending units at a local parts store. They will be wrong. Buy them from someone that specializes in these trucks like:

http://www.classicheartbeat.com/electrical_p-4.htm

Here is a link for information on the TCS. (Transmission Controlled Spark).
I don't believe that's what you are asking about. You'll have to click it again to make the diagram enlarge.

http://img232.imageshack.us/img232/1226/tcs14bb.jpg

Belowing are pictures showing the Temperature sending units, the gauge and the light. The Temperature warning light is on the far right passenger side. I use that to remember that the temperature sending unit for the light (single blade) goes on the same side.
You can't tell from the picture, but the light reads TEMP.

Thanks for the clarification!

CEE1NG_RED · 07-23-2012, 03:29 AM

What size wires did you use?

**derotoreut** · 07-24-2012, 09:08 AM

Agreed that you do not want to buy these from a parts store. Get them from someone that knows these trucks. I bought an aftermarket ignition switch and it didn't work properly. It is supposed to ground during cranking so that the idiot lights come on when you are starting the truck. Mine wouldn't light. I finally traced it back to the aftermarket switch. Once I replaced it with an OEM AC Delco switch I had no problem.

12-17-2011, 10:29 PM	#1
Handmedown Registered User Join Date: Feb 2011 Location: Richland,wa Posts: 95	Temp sending unit I have a 72 350. It has temp sending unit on both sides. I know one is for tcs and one for temp gauge. Driver side has one little post and pass side has one blade. Question is which one is which, I want to plug tcs side. Thanks

12-18-2011, 09:39 AM	#2
REEDS 72 Registered User Join Date: Apr 2011 Location: AMERICAN FORK, UTAH Posts: 535	Re: Temp sending unit What is tcs becouse my 72 BB 402 is the same way.

12-18-2011, 11:31 AM	#3
Sport/Truck Sierra Grande Club Join Date: Jan 2007 Location: New Mexico USA Posts: 2,433	Re: Temp sending unit You want the one on the driver's side (single post). __________________ 1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe.

12-18-2011, 11:36 AM	#5
Legolas894 Chemist under the hood... Join Date: Apr 2009 Location: Fort Erie,ON, Canada Posts: 617	Re: Temp sending unit I think what he's saying that one is for the temperature switch (for TEMP light) and the other is the temperature sender for the temp gauge. I think the probe with the post/terminal is for the sender (to the gauge) and the probe with the blade is for the switch (dash light). LMC truck has a good picture in their 67-72 catalog (pg 155). http://www.lmctruck.com/icatalog/cb/full.aspx?Page=155 __________________ Current fleet: 2013 GMC Sierra, 5.3L, 4x4 1988 GMC Sierra, 305, Auto 1984 Jeep Grand Wagoneer, 360 V8 1997 VW Cabrio, 2.0L 2017 Toyota Rav4, 2.5L Stuff I wish I still had: 2013 Toyota Matrix [RIP] 1967 GMC 910 Fleetside, 283 V8 [1st Love-SOLD] 1987 Jeep Cherokee Laredo 4X4, 4.0 I-6 [SOLD} 1994 Chevrolet Caprice Classic, 5.7LV8 [SOLD] 1995 Chevrolet Astro AWD, 4.3L V6 (RIP) 1998 Chevrolet Suburban 4x4, 5.7L V8 [SOLD]

12-18-2011, 11:44 AM	#6
Sport/Truck Sierra Grande Club Join Date: Jan 2007 Location: New Mexico USA Posts: 2,433	Re: Temp sending unit ^ both with and w/o gages go on the drivers side. __________________ 1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe.

12-18-2011, 11:53 AM	#7
Sport/Truck Sierra Grande Club Join Date: Jan 2007 Location: New Mexico USA Posts: 2,433	Re: Temp sending unit Here's a wiring diagram but it don't show the TCS system. http://www.boomspeed.com/bofh1968/ch...ng_diagram.pdf __________________ 1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe.

12-18-2011, 12:30 PM	#8
FLcustom10 Registered User Join Date: Feb 2007 Location: Tallahassee, FL Posts: 322	Re: Temp sending unit Different years have different options. The 1972 has both a temperature gauge and a temperature warning light. The drivers side is the single post for the Temperature gauge. The passenger side is the single blade for the Temperature warning light. Do not buy these sending units at a local parts store. They will be wrong. Buy them from someone that specializes in these trucks like: http://www.classicheartbeat.com/electrical_p-4.htm Here is a link for information on the TCS. (Transmission Controlled Spark). I don't believe that's what you are asking about. You'll have to click it again to make the diagram enlarge. http://img232.imageshack.us/img232/1226/tcs14bb.jpg Below are pictures showing the Temperature sending units, the gauge and the light. The Temperature warning light is on the far right passenger side. I use that to remember that the temperature sending unit for the light (single blade) goes on the same side. You can't tell from the picture, but the light reads TEMP. Attached Images Last edited by FLcustom10; 12-18-2011 at 12:58 PM.

07-23-2012, 03:29 AM	#10
CEE1NG_RED Registered User Join Date: Oct 2009 Location: LBC California Posts: 497	Re: Temp sending unit What size wires did you use? __________________ - 1967 Chevrolet C/10 SWB fleetside (New Project). - 1969 Chevrolet C/10 SWB fleetside (SOLD) - 2000 Ford Mustang 232 (DD) - 2003 Ford SVT Cobra "Terminator" 281 (Once in a blue moon driver/weekend driver)

07-24-2012, 09:08 AM	#11
derotoreut Roto Reuter thats the name... Join Date: Feb 2010 Location: Darien, NY Posts: 1,853	Re: Temp sending unit Agreed that you do not want to buy these from a parts store. Get them from someone that knows these trucks. I bought an aftermarket ignition switch and it didn't work properly. It is supposed to ground during cranking so that the idiot lights come on when you are starting the truck. Mine wouldn't light. I finally traced it back to the aftermarket switch. Once I replaced it with an OEM AC Delco switch I had no problem. __________________ ~ Dan My 70 K10 SWB build:http://67-72chevytrucks.com/vboard/s...d.php?t=782232 My 71 SWB build:http://67-72chevytrucks.com/vboard/s...d.php?t=651394 1970 SWB Fleet K10 4X4, 5.3L LM7, 4L60E, Dakota Digital RTX, Vintage Air, Ididit tilt 1971 SWB Fleet C10 - Original SWB Arizona truck, new custom restoration project "Kick out your motor and drive while you're still alive - kick it out!" - Heart 1977



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