instrument temp dial in the red

[colincolin64]

Hi there can anyone help please
I have a 1984 t25 water-cooled
The temp gauge is saying I am in the red it is right over and I have bleed the system fully and no trapped air I have replaced temperature sensor. I have checked engine block with a infrared temperature gauge and it's reading normal but the dial still right over
Any suggestions wot to do as the temperature gauge dial knackered is that possible sorry I am new to this cheers colin

[ChrisTriple]

If you leave the wire off the sensor what happens? The needle shouldn't move. Then if you ground the wire out on the engine it should move all the way to the right.

[colincolin64]

Yea mate that happens I done that aswell and all good there if I take it off it drop back down of it ground it it goes back up .does that mean the temperature gauge OK?? Cheers colin

[ChrisTriple]

Sounds too me like you have a knackered sensor to me and yes I'd say the gauge was working ok

[colincolin64]

I have put a brand new one in today and it still doing it that's why I'm confused cheers tho for your replies

[Stannerz]

Hi
I a
have a similar problem engine temp is normal but the gauge is reading hot nearly all the way over to the right!
Is there anyway to adjust the gauge/ bi metalic switch?

[ChrisTriple]

I have put a brand new one in today and it still doing it that's why I'm confused cheers tho for your replies

Just because its new it doesn't mean it's not faulty. Why did you put a new one in, in the first place?

[ChrisTriple]

Hi
I a
have a similar problem engine temp is normal but the gauge is reading hot nearly all the way over to the right!
Is there anyway to adjust the gauge/ bi metalic switch?

I don't think so no. Have you tried the above?

[colincolin64]

I just changed the temperature sensor hoping it would cure the problem I didn't know what else to do

[Smiffo]

I just changed the temperature sensor hoping it would cure the problem I didn't know what else to do

Hi Colin.

You are going to need to measure resistance across the sensor, really.
I don't know what the range should be, but at cold it should be within a certain value range and a different range when hot.

Do both new and old sensors so you have a comparison and post results here.

I don't know what values they should be, but if someone here doesn't know, it will be written somewhere.
Without doing the above you will resort to guess work - which will add to frustration IMO.

[Mocki]

to the OP 1984, so its a single pole to thermostat housing earth sender
if you take the wire off the sender and "earth" it to the thermostat housing , the guage should go to the top and trigger the over temp light flashing
it should not move when the wire is disconnected and not "earthed"

[colincolin64]

OK guys thankyou I will try these things when I get home if not to late thanks for all replies it all helps cheers

[Smiffo]

Also look at the coolant level and sender in the header tank...

Have a read of this link: http://forums.kombiclub.com/threads/t3- ... ned.46058/" onclick="window.open(this.href);return false;

I knew I had read something somewhere - once - that mentioned the coolant level sender, so I did some digging.
It isn't the thread I was thinking of, but certainly worth noting.

The coolant level sender also does something with the temp gauge and red LED.
It was a method of alerting you to low coolant apparently....

Maybe something else to look at once you have double checked the temp sensor. Just check one thing at a time.

E D I T: Also found this - which should be in the WIKI as it is very good.....

http://archive.club8090.co.uk/viewtopic ... 79be8f913b" onclick="window.open(this.href);return false;

[Mocki]

not sure i agree with that first link, two of our vans ( a 83 and a 84 )have a early relay (43) and neither make the needle move if its low coolant warning , i ve personally never seen it happen that way

but i guess its worth swapping the relay out for a known good one

[Smiffo]

not sure i agree with that first link, two of our vans ( a 83 and a 84 )have a early relay (43) and neither make the needle move if its low coolant warning , i ve personally never seen it happen that way

but i guess its worth swapping the relay out for a known good one

That's interesting to know.
I have a late 89 van, so I might disconnect the coolant level sensor tomorrow - just for a test - which I assume would have the same effect as low coolant.

At least we will know what late ones do, but it doesn't help the OP I suppose.
I am assuming if you unplug your sender then Mocki, you just get a flashing red light?