My bad, I don't know why I keep wanting to call it a radiator. Yeah, I think that the issues have been found and tended to. This was literally a brand new amp, kinda ridiculous that Fender would forget a grommet and have one of those pins stuck between the metal and the tank. When I put it back into place it took a reasonable amount of force to do so, it wouldn't have just gotten stuck there by accident.

Anyways, I think this thread's come to an end. Thanks everyone for your help! I definitely learned a thing or two even though this was an easy fix.

Okay, back again,

So I isolated the reverb tank from the amp and played for about ten minutes, more than enough time to provoke the hum, and I had no troubles. After that, I put the reverb tank back into the amp as close to the front as possible, past the initial place where it was screwed down, hopefully to pick up whatever was causing the issue. I only encounter a small hum, which was constant and low, not as annoying as the hum I've been talking about this entire time. I may go back and put it on top of the mounting holes to see if I still pick the small hum there, or if I get the increasing in volume hum again.

I forgot to mention that only two of the grommets were actually in place when I took the radiator out of the bag, so one was flying around in there which may have added to the lack of balance and the increasing volume of the hum, this time around I had all three in which may have fixed the issue but I don't want to stop there, just in case.

So I took a few pictures for you guys of the inside of the radiator, as I do have a question in regards to it. As I said, all the cables seem fine and are all making proper contact.

So if you take a look at this guy, you can see those two grommets on the inside aren't the same... I'm not sure if that was done on purpose and whether I should leave them alone or just put the one on the right into place. This also makes the entire innards off-centered - http://i.imgur.com/cnzgCql.jpg

Here's a picture of it longwise - http://i.imgur.com/1zbsyTm.jpg

And two pictures of the circuit boards, excuse the quality - http://i.imgur.com/jONoYB5.jpg http://i.imgur.com/6jFunaP.jpg

Okay, that makes a lot more sense!

So just to clarify, I believe the issue is that the missing grommet offsets the reverb tank's balance causing the hum. This makes sense to me because whenever I moved it, I must have set it back up to a balanced position, then whenever the amp moved or whatever, the tank was off balanced again since there was only 3 grommets like a lopsided chair.

As for the setup itsslf,

There's a bag that covers the reverb tank with four rubber grommets on top of the price of cardboard. The bag is screwed down to the bottom of the amp, the screws going through the cardboard to keep it all in place.

Hey guys!

So after reading your comments I decided to go ahead and inspect the reverb tank, and I think I found the culprit.

g1, the pedal included with the amp literally cuts out reverb altogether as if you literally unplugged the tank while it's on, whereas the pedal is like incremental. I'm not 100% sure on that one but I think that's how it works. As for the level of feedback when I adjust the pot, it makes no difference. If the pot is above say, 4, it would trigger the hum. If I were to play with the pot on 1-3, just as an example, there would be no issue at all.

Roly, the connections all seemed fine in there and everything is nice and clean in there. After inspecting all the wires they seemed fine as well.

So to answer your question phatt, the tank sits in a nice bag, and sits on top of a piece of cardboard inside this bag which I believe is standard. However, if you take a look at the pictures below, I was given only three of these silicon grommets and little brass (?) metal pieces to put inside the four larger holes which I assume is to hold the tank in place on top of the cardboard to avoid any issues w/ the springs moving unnecessarily. Now if I'm not mistaken, there should be four.

http://i.imgur.com/SaRFnCk.jpg
http://i.imgur.com/tLdvrll.jpg

So I've lost hope in Fender since it seems like they're more like Ikea with all the missing parts and poor build quality. Even one of the feet was screwed on improperly. So my question is now; where the hell do I pick up a new set of these?

Also a few more side-notes, I recall reading a pretty interesting/funny thread somewhere else about the cardboard that they put these reverb tanks on top of, and how you get a better vibe with "vintage cardboard" and whatnot as a joke. But on a serious note, someone asked a question about possibly replacing that cardboard with a piece of metal or another material such as foam, would this be beneficial at all?

I also noticed that Fender seemed to do a really shitty job wiring this and they even hot-glued the reverb connections to the circuit board? Would I be better off removing that and re-soldering it on there? I've never worked on re-soldering connections on amplifiers but I do have experience with guitars so I'm not sure if this is standard... I do recall a story online of an amp-repair guy re-soldering connections and improving tone/sound from that. Would you guys recommend doing that in the future? Because seriously, hot glue seems like a cheap solution, correct me if I'm wrong.

http://i.imgur.com/UMZUuql.jpg

Not sure if this is the right place to post this but here I go,

So the issue has to do with Reverb. With my limited knowledge I think it might have to do with the reverb tank, or the tube which controls reverb (I'm not sure if this one is right at all). So if I turn the reverb on, and put the knob anywhere past four, the amp will start humming. The humming starts off quiet, and progressively gets louder and louder, probably within a span of ten seconds to a minute until it's just unbearable. So when this issue came about I decided not to even mess with anything, but I decided to troubleshoot around. So once it started humming, if I turned the reverb knob back down to zero, the hum will continue to go on. If during the humming, I use the provided pedal which turns reverb on/off completely, to turn reverb off, the hum will go away until I hit the button to turn reverb back on. The hum will happen regardless of what volume the amp is at, say it begins humming and I turn the volume/master/drive knobs to zero, it'll keep humming. If I put it in standby and unplug my guitar, then hit standby again, it'll start to hum and progressively get louder and louder. The only temporary solution I noticed, which would only last for a few days or until I move my amp or something is to shimmy the reverb tank away from the speaker, but don't hold me on that one. When I did this a few days ago the hum was completely gone and I was able throw the reverb knob all the way over to twelve without a hum. Also on some occasions if I shook the amp a little, enough to hear the reverb coils/strings or whatever make that weird swishing noise, the hum would go away, but if I were to start playing again the hum would come back and do its thing.

So with all that said, do you have any idea what the issue could be? I'd really prefer to fix it myself if it's simple enough, I just don't want to start poking at stuff I shouldn't be until I know what it is and I should be able to fix it.