Why is my gas gauge stuck on E? (pics)

Can anyone give any advice on why my gas tank is stuck on E? I've included pics to help with the visual.

 

There can be several problems:
1) the tank is empty
2)the sender is broken--ground the pink wire, if the gauge goes up, the problem is the sender
3)the gauge is broken--it doesn't go up when the pink wire is grounded

This assumes it is getting power through the purple wire.

 

!. No gas in tank? 2. sending unit "arm" or "bobber" damaged OR hung? 3. resister wraped sensor corroded or damaged? 4. wiring faulty (SO many ways for this to happen). 5. improperly wired at guage terminals? 6. poor or no current? 7. bad guage, busted needle?
You haven't said... 1. New to boat & have no idea if it ever worked. 2. was working untill some "event" took place. 3. Have borrowed a guage & things work. 4. Have aquired another sending unit & old guage works. Have a volt meter AND???? 5. Know how to read resistance in a wire. 6. Have removed old sending unit & inspected it.
Hope these things help, because I get no "feeling" by looking at the pics. (just kidding), the pics show a average installation & wiring. Hey! It don't work now right? So tear into it, you can't hurt it. Spray everthing with a penetrant overnight then check for "continuity of the wires. THEN the voltage into the tank. Then take the sender out and check for vusable problems. THEN, "ohm" the resestence at the sender. Then hook up a borrowed guage. THEN it's time to check the least likely, the guage itself.

 

Thank you Ted(very thorough) and Gonzo for your responses. I guess there is a small art form in posting a question, but I'll get better The last time my gauge worked was 2 summers ago and there was not an event that coincided. It just started registering ONLY when it was full and when I ran it for about an hour, it went to empty. Fill it up, same thing over again. But now it's on E all the time. It's raining here so I cant go check on the tank right now, but I will when the weather breaks and post my results. Thanks again.

 

Take note of what Gonzo said, earth the pink wire if the guage moves you have illiminated ,--no gas, bent needles, no power.

Its the number one start check.

Basically if it does move then you have iether no gas or the sender is not working. Thats ALL it can be. If it doesnt move then you read Teds post again.

These are normally quite cheap and or can be repaired. They are soooo simple.