VintAGE-Vans

Would you like to react to this message? Create an account in a few clicks or log in to continue.

BRINGING IT ALL TOGETHER.... A's, G's & E's

Search Query
Display results as : Posts Topics
Advanced Search

You are not connected. Please login or register

3 posters

TEMP light always on?

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°1

TEMP light always on?

Post by Scott Sat Aug 20, 2011 6:04 pm

When I turn the key to on the light is off, but as soon as I start the engine the TEMP light comes on..?

I pulled a new wire, and switched out the sensor today, but still it shines.

If I understand it, the hot wire comes from the fuse block to the light, and then the ground wire goes from the light to the sensor.

What am I missing?

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°2

Re: TEMP light always on?

Post by donivan65 Sat Aug 20, 2011 6:55 pm

,,,,,,the wire goes to the temperature sender AND oil pressure sender,,,,,does the light go out if you unplug the temp sender or oil sender when it is running?

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°3

Re: TEMP light always on?

Post by Scott Sun Aug 21, 2011 7:50 am

When I rewired I pulled separate wires to the oil sender and temperature sender.

Good question, I'll go see what happens when I unplug it from the sender, and then trace back to the dash light to find out where it's grounding.

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°4

Re: TEMP light always on?

Post by Scott Sun Aug 21, 2011 12:40 pm

Alright, now I'm a little confused.

First I figured out that the sensor for the gauge was wired to the dummy light, and the sensor for the dummy light was tied to the gauge.

To answer your question, yes, when I disconnect the wire from the sensor that feeds the dummy light, the light goes off. So now I don't get why the sensor is always completing the ground.

Also, before I moved the wire for the gauge from the dummy light sensor it was reading 180, but as soon as I moved it to it's sensor it jumped to 230..?

The gauge is an old Sunpro that came with the van, maybe dump it and go with a new one?

The dummy light sensor is one that NAPA found for me since the factory sensor for the L6 wouldn't fit the 3/8" hole in the engine.

Any ideas?

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°5

Re: TEMP light always on?

Post by donivan65 Sun Aug 21, 2011 7:09 pm

,,,,,,,and you think you're confused????

You are mixing everything up,,,,,there are senders, sensors and switches,,,,,they do different things,,,,,the idiot light requires a switch,,,it grounds the wire when the coolant gets too hot,and that puts the light on,,,,a Temp gauge needs a variable sender,,,,it's resistance changes with the temperature of the coolant and that causes the needle to move. You need the right type that matches the system you are using,,,,they basically are a matched set.

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°6

Re: TEMP light always on?

Post by Scott Sun Aug 21, 2011 8:22 pm

Yeah, and I got them straight today, and was very careful to buy the right sensor when I replaced the dummy light one, but you can what I wrote for the results. I planned on replacing the gauge anyway, just not right away. Right now it's mounted in the doghouse, but the plan was to get a new one and mount it where the radio cut-out is on the dash. I'll go ahead and get that in with the sensor in the package.

The guy at NAPA seemed pretty sure that the sensor he sold me would be a good replacement, but now that I'm looking at the part number it says it's good for a gauge, temp light, and electric fan switch. The factory sensor for the L6 is to big for the hole, so they dug this one up for me. Is there any other place in the block, besides the front, that I can put in the sensor? My old engine had a place in the head, near the front over the exhaust manifold, but this head doesn't have it.

I appreciate the help Donivan, I know all this is simple stuff to you.

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°7

Re: TEMP light always on?

Post by donivan65 Sun Aug 21, 2011 9:33 pm

Seems to me there are 5 holes to mount a coolant sender onto a 6 cylinder engine,,,,,,the original is in the head on the left side, right below the oil filler cap,,,,then it seems you got the thermostat housing adapter that has 3 more in it like in this post of yours,,,,,finally, there are thermostat housings that have a hole threaded into them for a sending unit,,,,,,

https://vintage-vans.forumotion.com/t22898-thermostat-housing-adapter-plate-250-inline-6-cylinder

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°8

Re: TEMP light always on?

Post by donivan65 Sun Aug 21, 2011 9:56 pm

TEMP light always on? Threm_11

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°9

Re: TEMP light always on?

Post by Scott Mon Aug 22, 2011 6:55 am

The problem with the housing I bought is the holes are one size to small for the factory sensor, so NAPA handed me one that would fit, but it looked just like the one I replaced, and has the same problem. I considered re-threading one of the housing ports up to the size of the factory sensor, but I don't have the tools, and think I would probably crack it if I tried. I also have a water outlet like you have above, but I ran a tube from there to the overflow tank to help with trapped air since the water outlet is higher then the return on my radiator.

Having to deal with issues like this makes a good case for keeping everything factory doesn't it?

NAPA sold me an Echlin ts6178, what I'm kinda surprised didn't work, I just figured a dummy light sensor was a dummy light sensor, was a dummy light sensor. Strange, I went back and looked it up at the NAPA site to be sure they sold me a Light Sensor, and not a Gauge Sensor, but according to their site it's good for all three. I'm not believing it, it should be gradual for a gauge, and on / off for a fan or dummy light.

TEMP light always on? Screen10

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°10

Re: TEMP light always on?

Post by donivan65 Mon Aug 22, 2011 8:34 am

Fan and Idiot light senders are off and come on when they sense about 240 degrees,,,,,so a gauge sender is different. i would say there are thermostat housings and adapters that have the 2 big holes in them,,,,they would be used on smog controlled vehicles that use thermal switches. These would be from the 1970's. Also that recirc line don't need to go to the thermostat housing, the REAL ones go to a coupling that is inserted into the upper radiator hose.

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°11

Re: TEMP light always on?

Post by Scott Mon Aug 22, 2011 8:53 am

I found this one at Speedway, do you know of a different source? I'd be happy with a plan GM one if they made them.

TEMP light always on? Screen12

I also found this one, but I'd have to measure the openings to be sure it would work.

TEMP light always on? Mishim10

Although I don't know how I feel about having Mishimoto parts on my van. Really can't get further from American Made then that..

donivan65: Governor; Number of posts : 12220
Location : San Diego, California
Registration date : 2008-05-12

Post n°12

Re: TEMP light always on?

Post by donivan65 Mon Aug 22, 2011 11:22 am

That recirc line that goes into the upper hose don't have to be anything special,,,,a plumber or muffler shop could install a nipple into a piece of tubing and it would work until you found something better or prettier,,,,,,,,,,

TEMP light always on? Harry_32

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°13

Re: TEMP light always on?

Post by Scott Tue Sep 27, 2011 8:11 am

Last weekend I installed the factory sensor, and moved that air bleed down the hose.

TEMP light always on? Hpim4310

The Temp Light is now off when I start the van, but if I bypass the sensor it lights-up. Amazing what the right part will do huh? Very Happy

Very Happy

I guess the logic of a sensor is a sensor is a sensor has been proven wrong.

Hopefully next weekend I can get a replacement water gauge installed, and then go back to adjusting the carb.

Thanks for the hope Donivan.

RodStRace: Number of posts : 3046
Location : Chino Valley
Registration date : 2010-01-21

Post n°14

Re: TEMP light always on?

Post by RodStRace Tue Sep 27, 2011 11:48 am

Just to clarify, 'cause you are driving me nuts with the terms...

Switch= like a light switch. Off or on. Used for your light, not a gauge. Almost always small around. Since they are open in normal and closed when wrong, they can be switched, but understand that GM may use a different limit than Ford, etc. Typical oil pressure switch is on at around 8-10 PSI, some are as low as 3 PSI.

Sender/Sensor= it changes the resistance, like a dimmer in your house. Various resistances for older gauges, so these are not all the same. New computer stuff is often the same resistance to value, but not always. The older ones are usually much larger around. Modern computer ones are mostly small and have the special connector plug.
Sender is analog, used for gauges, sensor is usually solid state, used as a computer input.

Scott: Number of posts : 1651
Location : Anoka, MN
Age : 54
Registration date : 2008-05-20

Post n°15

Re: TEMP light always on?

Post by Scott Tue Sep 27, 2011 1:09 pm

I got that the dash light, or dummy light, sensor is just a switch that triggers at a certain temperature, and that a gauge sensor passes more and more electricity as it heats up. What I threw me was that you can't just use any Ford, Chevy, Dodge, on / off sensor for the light. I just figured the trigger point for the switch was probably the same.

But like you said RodStRace, the different sensors I was trying were probably build to different specs. I just wanted people to be able to read from the thread and not make the same mistake that I did.

Sponsored content

Sponsored content

Post n°16

Re: TEMP light always on?

Post by Sponsored content

Similar topics

» glass tail light turn signal light covers
» engine temp
» Normal opp. temp.?
» temp guage
» temp guage

Current date/time is Fri Apr 26, 2024 11:04 pm