Instrument panel is melting away (overheating ?)...

[paraterra]

Hi everybody

I have a Nissan Safari 1990 possibly a MQ model (diesel, 24V). It started with temp gauge and now also with the fuel gauge. The pics explain it better than I can describe:
IMG-20160202-WA0001.jpeg

I tried to take everything apart and this is how it looks like:
IMG-20160202-WA0004.jpegIMG-20160202-WA0006.jpeg

To me it seems the little white coils are heating up as it matches the melting on the fuel gauge.

I live in paraguay. It's difficult here to find good electricians and mechanics. For now I have disconnected the plugs for those gauges to prevent further damage.

Any advice or hints for possible problem sources are appreciated.

Thx in advance

[happygu]

Paraterra,

That is quite unusual, especially if the car is all original.

Do you know if the instrument cluster is original or not ? ..... it looks like you have a cluster for 12V and are running 24V through it.

The same thing happens to Electric Doors strikes that we sell, and there are 12 and 24V types. If someone hooks up 24V to a 12V Coil, it runs for a while, but gives off heaps of heat until it burns out.

If it is all original, I would suspect that there is some sort of voltage regulator to adapt the 24V down to 12V and it is breaking down and not doing its job.

I would be checking voltages with a multimeter to see what you have got there.

[mudnut]

If it is only two gauge coils doing it, maybe they have been replaced with 12v ones. If it is all doing it, I would imagine it is as happygu posted.

As a matter of interest, check to see what voltage the alternator is putting out.

[the evil twin]

snip...

To me it seems the little white coils are heating up as it matches the melting on the fuel gauge.

The 'little white coils' are hot wires for the gauges.
The metal 'D' shape they are wrapped around is spring formed bimetalic
The more current that flows the hotter the wire gets, the more the metal changes shape and pulls the pointer around the dial.

Do the gauges seem to work as they should?
IE if the tank is 1/2 full or the temp is cold does the gauge correspond.

It may be that the power supply for the instruments has crapped itself

[paraterra]

Thx everybody

This gives me a lead for my search.

I have bought this car 3 years ago and have to assume pretty much nothing is original in this car. It had originally right hand wheel and was transformed to left side. But it seemed to run without this problem for a long time.

I had the wiring redone a year ago (I did the big mistake not to attend the work that was done) and since then this problem started to occur. First only with the temp gauge, then it stopped. and just recently it started again, got worse and started on the fuel gauge side as well

The car is 24V; 2 * 12V batteries. I'll check the voltages coming to the instruments.

Is there a way I can identify whether the cluster (or single instrument) is for 12V or 24V ?

What is the function of the hot wire coil between the two gauges ?

[happygu]

As you have had it re-wired, can you take it back to the guy that did it, as to me, it seems like he may have tapped a power feed for something else off the wrong point, causing the overheating you currently have.

If the gauges haven't been working properly, or have been inconsistent, then either this would be a fairly good guess, or the previous guess of having the wrong voltage being fed in...


Mic

[mudnut]

The voltmeter on a 12v gauge cluster only goes up to 18v where as yours goes up to 36volts.

[Yendor]

The temperature gauge and fuel gauge share a voltage regulator. The white coil in the middle of the two gauges looks like the remains of one.

The oil pressure gauge will have it's own voltage regulator. If this gauge was still working measure the voltage on the output side. This will tell you what voltage the gauges are.

An instrument repair shop should be able to repair the cluster for you. They will replace the mechanical voltage regulators with electronic ones and should be able to make up new facias.

[the evil twin]

What is the function of the hot wire coil between the two gauges ?

Do the gauges seem to work as they should?
IE if the tank is 1/2 full or the temp is cold does the gauge correspond.

It may be that the power supply for the instruments has crapped itself

The temperature gauge and fuel gauge share a voltage regulator. The white coil in the middle of the two gauges looks like the remains of one.

The oil pressure gauge will have it's own voltage regulator. If this gauge was still working measure the voltage on the output side. This will tell you what voltage the gauges are.

An instrument repair shop should be able to repair the cluster for you. They will replace the mechanical voltage regulators with electronic ones and should be able to make up new facias.

Onya Rodney...
I wasn't familiar how those older 24 volt jobbies handled their power for the hot gauges.
Just knew they were known to cook 'em every now and then.
Learnt yet another thing today

[paraterra]

As you have had it re-wired, can you take it back to the guy that did it, as to me, it seems like he may have tapped a power feed for something else off the wrong point, causing the overheating you currently have.

If the gauges haven't been working properly, or have been inconsistent, then either this would be a fairly good guess, or the previous guess of having the wrong voltage being fed in...


Mic

You're right...

Paraguay is 3. world and It's really a bit difficult here when comes to find a good mechanic (electrician, plumber, etc). Mostly they are ok fixing the obvious things, but when it comes to details it's rather problematic. Further more people will still try to "fix" something, even when the problem has went beyond their capability.

So the answers in this thread are really helping me to get a basic understanding of the possible issue and the way this part of the car works.

When I take it back to the guy (or another electrician) I have a chance to overview/judge the work being done. This is the most important lesson I have learned here in the last couple of years when it comes to repair things; you need to be present and overview the work done...

So all the comments, explanations are really appreciated