Because like all the other guages, each work independently of one another, and show different happenings going on with the engine. The tach itself could be bad, or maybe disconnected from the ignition system. You will need to find someone to troubleshoot it, if you want it fixed. If not, don't worry about it.
Check the fuse.
On a car, there is a float inside your gas tank. It is attached to a switch that sends the empty.....full signals to your fuel gauge.
It could be a number of different things; if the radio and other electrical things work with the key to acc. then it is most likely not electrical. It would be best to take it to a mechanic and have them scan it to see what is wrong. Hope this helps.
You take the car to a professional. You do not have the proper tools and gauges to do this yourself. You have a leak that needs to be repaired or you would not need to recharge the A/C.
If your 1949 truck is a CHEVY or GMC and it still has the original electrical system, it would be 6 volt, negative ground. If it is a Dodge or a Ford with the oringinal electrical system it would be 6 volt, positive ground.
Electrical connection issue.
One can find information about depth gauges online. However, for tire depth gauges the best place would be the local automotive store, and for the chainsaw depth gauge the best place to go is to a home improvement store.
Fuel [Petrol] Gauges that Fail to WorkAlthough there could be one or more other causes for a fuel/Petrol gauge to fail to work, the answer is YES, a "blown" fuse could cause the gauge to not work.
It would be better to write: My gas gauge reads empty. Note that 'gauge' is singular, so it needs the singular verb, reads. If you had several cars all with gas gauges that read empty, then the verb would be read.
A pressure gauge is an instrument that measures the pressure in a vessel, a line, or whatever the pressure gauge is connected to. Pressure gauges come in at least two different types: differential pressure gauges, and absolute pressure gauges. Differential pressure gauges measure - surprise - DIFFERENCES in pressure. Pressure gauges that read "zero" when not attached to anything would actually be differential gauges that measure the difference between atmospheric pressure and the pressure of whatever they are attached to. Vacuum gauges are differential gauges that measure how far BELOW atmospheric pressure the pressure is in a vessel or pipe. Gauges that measure "gauge pressure" are just differential gauges that are calibrated to measure zero at atmospheric pressure. Absolute pressure gauges would only read "zero" if they were attached to an absolute vacuum. A common type of absolute pressure gauge is a barometer. Strictly speaking, a mercury barometer is really a differential gauge that measures the difference between the vapor pressure of the mercury and the surrounding atmosphere, but the vapor pressure of the mercury is so low that the error in treating it as an absolute pressure gauge is generally negligible. There are many different kinds of gauges used to measure pressure including: Instruments hydrostatic - These measure pressure according the height of a liquid in a column. The height of the liquid is proportional to the pressure. Common types of hydrostatic gauges include: manometers, McLeod gauges, and piston gauges. aneroid - The pressure sensing element may be a Bourdon, a diaphragm, a capsule, or a set of bellows, which will change shape with changes in the pressure of whatever the gauge is attached to. The deflection of the pressure sensing element is read by a linkage connected to a needle or by a secondary transducer. The most common secondary transducers in modern vacuum gauges measure a change in capacitance due to the mechanical deflection. Gauges that rely on a change in capacitance are often referred to as Baratron gauges. Electronic sensors thermal conductivity - including two wire and one wire gauges that measure pressure via changes in the thermal conductivity of the wires as they are placed under strain. Something like this is used in a lot of electronic bathroom scales. ionization gauges - These are primarily used for measurements of low-pressure gasses. They sense pressure indirectly by measuring the electrical ions produced when the gas is bombarded with electrons. Fewer ions will be produced by lower density gases. they have to be calibrated against another type of pressure gauge and depend on the gas being measured.
Ultrasonic thickness gauges can be found at any Grainger like store the reason you would need this type of gauge is if you are measuring coating or linings . The model type that would be best for you would need to be determined by the type of material you are working with.
It could be a fuse .That would be a starting place.
Air fuel ratio gauges rely on a sensor that is very much like an O2 sensor used in a car's emmission system. Therefore you would have to have 'bung' drilled and welded into your cars exhaust system to mount the sensor for the air/fuel gauge. After that, run the wiring and mount the gauge like any other aftermarket gauge.
I have no idea what you mean!... Standard gauges are 18 (regular earrings), 16 (smallest gauge of body jewelry, generally), 14 (also very standard) and then 12 and lower is getting to be large gauge for stretching. "1.6 gauge" does not exist, since gauges come in increments of 2 (and 0 gauge is an inch thick and very few people have such stretched holes!) And 14 WHAT? Millimeters? And if you know how long the jewelry is, and the gauge, then what size is left for you to be asking about?
Probably electrical, you may have accidentally unplugged a connector.