Urgent help Connecting an Oil temp gauge?

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Guni_GuGu
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Urgent help Connecting an Oil temp gauge?

Post by Guni_GuGu »

I think I'm one of the few in Australia with an FTO, with the factory OIL and Vac gauges on the centre console, still, the other day, I put in my new head unit, and my dickhead friend, was messing with it a bit too... we eventually got it working, but he did cut a lot of wires, without knowledge, before the head unit was working...

Then I went and had my alarm installed as well...

And well, now my oil gauge doesn't work :p

I've tried doing a bit of a search, but i'm not sure, where it went wrong? Was it something I did, when instlaling the head unit? Or was it the guy who did the alarm?

I know, when installing the head unit, there were 3 long wires coming from the "gauges" 2 yellows and a black (I think it was black), I couldn't work out, what the black one did, but the yellow ones, were light for the guages... So I connected them to the power source, and I wasn't too sure about the black, but I just left it un connected...

The vaccum gauge still operates normally, but my oil temp doesn't... apparently, it's always 0 degrees no matter how hard I drive it :p

Please help, because I'm taking my car back to the guy who did my alarm in the morning, and if it's something they've did, i'll get them to fix it... but if it's something in the center console, I can fix it..
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Boris
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Post by Boris »

Is the gauge a mechanical one or an electric one?

A mechanical one will have a sensor somwhere, normally you put it in the sump. If it is then, it just might be a coincidence that your sensor is broken.

I too can't remember how many wires mine has, but mine isn't working either, but i think it is because of the sensor,
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Guni_GuGu
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Post by Guni_GuGu »

Boris wrote:Is the gauge a mechanical one or an electric one?

A mechanical one will have a sensor somwhere, normally you put it in the sump. If it is then, it just might be a coincidence that your sensor is broken.

I too can't remember how many wires mine has, but mine isn't working either, but i think it is because of the sensor,
I'm pretty sure it's mechanical.. no idea really, and if I knew what the sensor looked like, and where the sump was, I'd try it :)
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Boris
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Post by Boris »

Hold on, if it's a mechanical one, it should be 2/3 wires and a large pipe or something as well... for the sensor right? Can't you just follow that to find the sensor?

Sometimes, you can fix the sensor by taking it out and I think cleaning it in "deisel" 8O Really can't remember.... could be Kerosine.... 8O

It's pretty hard and expensive exercise getting this fixed by someone, most mechanics can't be fucked unfortunatly... That's why mine is still not working... They just say get a new one...
fto12345
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Post by fto12345 »

Hi guys,

I'm about to install mine on my car and mine is mechanical...
But I am curious as to where to connect the sensor...

You mentioned about the oil sump...I was thinking there as well but where?
Where the oil sump screw is? so replace that with the sensor?
Or stick it to the oil sump on the outside? which most mechanics do as it's much easier that way, but I wouldn't want to do it like that...

Hey Boris, if yours is a mechanical one as well, would you be able to find out where your sensor is?

And if your gauge is not working and it's not the gauge and it's the sensor then it could be a problem with the sensor it self or the cable....all it is is a thick copper wire....so you should be able to repatch that.....but if it still doesn't work then I guess it's your sensor...

And if it's a mechanical one then there should only be 2 wires...2 for the light....and the black one should be the earth....normally is....If it's a mechanical one then no matter what you do with the wires, it wouldn't have any thing to do with the gauge not working, unless you've cut the actual sensor wire which is quite thick!

And Gunni, if yours is a mechanical one as well..can you see where your sensor is and let me know as I would love to install mine soon!

Thank you,
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Boris
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Post by Boris »

You only really have two options about installing a mechanical oil temp sensor.

1) Get someone to machine you a brass reducing bush, or a fitting so that your sensor fits into the sump plug. (Like mine)

2) Get someone to make another hole in the sump, with a thread to screw in your sensor, this method is better but more expensive. Richard H has his done this way. It saves you taking out the sensor every service.

I'm going to change my oil this weeken, so I will give my sensor a good clean and see if it helps...
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Post by fto12345 »

So where your oil sump screw is, you can put your sensor there?
I might try that as I was thinking of doing that as well but just wasn't sure...

But maybe I should wait till I change my engine oil and do it all at the same time...
:)

Btw, do you know of any easy way to pull those cables through the firewall through that damn small hole where all the wires go through and now you can't seem to find a room to put any thing through it any more??

I guess you'll only know if you have ever tried to pull any thing through that hole!!!!
:)
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Boris
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Post by Boris »

I think if you search around there should be another couple of holes with gromets & plugs...

The problem is, you might need that fitting mate, and if you don't have it then you just would emty your oil.

I got my fitting re-done by a mechanic, cos the one the came with the car leaked... so best to get it done by some one that can machine, and make threads...
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Post by RallyMad »

Just thought I'd post here guys. Don't forget that with a mechanical type guage there should be two wires for the power and a copper feed, which flows oil to the guage to get the measurment. I'm not sure if this is what happens with oil gauages as you are all talking about feeds, but the oil and fuel pressure gauges I had where like this and I remvoed them because they where a fire threat flowing oil and fuel into the cabin. Are these gauges you guys are talking about use a sensor with a wire and not a copper runner like I'm talking about? :?
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Boris
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Post by Boris »

thanks mate... I wasn't actually aware of the oil flowing into the cabin via the cable, cos that's what i got...

Why do they do it like that? Very strange.... I wouldn't do it that way... :evil:
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Post by RallyMad »

No worries boris, I think it's just the way it used to be done. There are electric (my spelling sucks at the moment sorry) ones that don't do this. But they can be $100 or more more expensive than mehcanical ones. :cry:
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Post by fto12345 »

The fuel temp and oil temp gauges are different!

The mechanical fuel temp will have to have the fuel running towards the gauge in order to detect teh fuel temperature....And that is way it's illegal to have them in said cabin.

However, the mechanical oil temp doesn't do this.
All it is is a thick copper wire that transmits the temperature to the gague....that's all.....so if you get the mechanical one and put the sensor in a boilling water, the gauge will jump to 100 degree...it's not because it's sending the water to the gague, it's just picking up the temperature and the copper wire just sends it to the gague....
That's all...

I ahve fitted mine last night and it was a bit of a drama to pull the sensor through the firewall but got it through and stuck in where the sump screw goes in....the oil temp gague comes with different size screws to match, and one of the ones it came with it fitted perfectly into that socket....so I just replaced the sump screw with the gague sensor, and it's good since my sump screw was getting beaten up too much....I just didn't have the time to connect the wires for the light bulb...that's all...will do that soon...
But otherwise, it works perfectly fine and it looks good!
I like it!
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Boris
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Post by Boris »

Cool, i c now... 8O
So what does the sensor look like on the inside, the bit that is in the sump?

I just wanna know cos i wanna try and clean mine to try and get it to work... I'm hopefully gonna pull it out tommorow... Is there an obvious place where it can get gunky? etc... hmm...


I'm still unsure as to how a copper tube, can simply transmit the temperatuer acuratly all that distance... is the tube hollow? so the air in the tube just heats up right? :oops:

And I can't even find anything on the net about how they work.
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Post by RallyMad »

Boris wrote: I'm still unsure as to how a copper tube, can simply transmit the temperatuer acuratly all that distance... is the tube hollow?
Exactly mate, and the gauges I was talking about where very cheap and nasty, and where pressure gauges not tempreture gauges. So they flowed the liquid up to the guage to cheak the pressure in the system.
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Post by fto12345 »

It's just like having a metal spoon and you are stiring a boiling water...
eventually the metal heats up all the way to your hand.

but a copper is a better conductor of heat and it is insulated with rubber tube so that it doesn't loose too much heat..

I wouldn't say a mechanical one is that accurate.
It won't be as accurate as the electrical one.

It's pretty much same as having a analog speedo and a digital speedo. If you have the two put next to each other you'll see that eh two gives off different readings. That's becuase the electrical one is more accurate.

but I guess the gauges are a little different in that if you use a electrical one, then you are either using the sensors that are already there, or mix the reception by using the gauges own sensors as well as the sensors that are already there. either way the mechanical ones cannot give a more accurate reading then an electrical one.

that's all.

the tip of the copper where the sensor is, is just a long copper cylinder with the end blocked. The easiest way to see if it is working or not would be to take it out and clean it then dip it in a hot water. If the guague doesn't respond then it's obviously either your gauge it self or there are something wrong with the tip or the wire it self.

don't know how much more ideas i can get out at the moment....

Good luck!
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Guni_GuGu
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Post by Guni_GuGu »

I should say, it was rather easy to fix this problem.. basically, when I removed my old deck last week, I also cut a red wire coming down, from where the gauges were.. for some stupid reason, I connected to this earth... don't ask :p

Anyways, I've since then just connected it, to the iginition power, that is also connected to the new head unit, and she works, just like she always did...

Now, on a semi related note, i've notcied some like crackling kinda on the inside of the gauges like window bit... can i fix this anyhow? because it's reallly annoying!!!
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Post by Boris »

Aren't ther wires just for the lights of the gauge? And the copper tube is the temperature?

Ginu_Gugu, are you saying that you fixed your gauge by simply re-doing the wiring? 8O

I'm confused... :oops:
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Post by Guni_GuGu »

Boris wrote:Aren't ther wires just for the lights of the gauge? And the copper tube is the temperature?

Ginu_Gugu, are you saying that you fixed your gauge by simply re-doing the wiring? 8O

I'm confused... :oops:
Basically, me and my buddy went and installed a new headunit in my car, the next day, I had an alarm put in.. when I took home my car, I noticed the oil temp gauge (where most people have a clock) wasn't working..

So at somepoint, something went wrong. I rememberd my buddy cutting basically every wire, and there were 3 wires coming from the guages, 2 yellow ones, which were lights, and I simply connected to the "dash lights wires" and one red wire, which I couldn't figure out for the life of me what it did... when i originnallly wired up everything, I connected it to earth... but yesterday, I felt like trying an experiemnt, and connceted it to the iginition power lead, which also runs into the deck.. and well, now it worked... so all that was wrong, was the gauge needed some sort of power to operate, and that wire had been connected to earth instead of currant.

I think the actual sensor and all that crap was all fine, it just that, I didn't know, at what point the gauge stop working, and though maybe the guys who installed my alarm mite of messed it up when installing the alarm, and could've knocked the sensor out or something...

On the semi-related note, can I possible clean the glass things, of those gauges? because one of mine is cracking and starting to peel looks ugly, and is it possible to change the light behind it, because it has this ugly yellow light...
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Post by fto12345 »

So after all this, what you had was an electrical gauge, and not a mechanical gauge.

If you don't specify exatly what you have, people can't help you much you know!

The bulbs should be a normal bulb that you can pull out from the back.
Otherwise, just use a condom and cover up the light to give off a different colour. They work quite well actually.
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Post by Boris »

What size of gauge does the fto take? I think it's either 46mm or is it 52mm ?
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