Nick,
I removed to top plastic cover earlier and it was not overly dusty and I was not attacked by any killer dust bunnies.
Glad to hear it
Another thing to check is down inside/on the fan impeller itself - at one point the impeller on mine had accumulated enough residual dust that I thought it might be a wise idea to clean it off with some q-tips and rubbing alcohol, just in case that was throwing it out of balance or something ...
FWIW, mine is not generally overly dusty either ..... however it will periodically make noise, as though the impeller for the fan is dragging or rubbing against the plastic cover ..... sometimes this goes away fairly quickly, other times it will continue for quite awhile ... and still other times it never even occurs .... what causes it, I'm not particularly sure ....
I put everything back together and let it sit for about 15 minutes and then tried starting it. To my amazement it started right up and pumped out some nice heat. Unfortunately the heat only lasted about 45 minutes before the unit shut down again. It sat for about 25 minutes and I just tried restarting it and it kicked on but it sounds like the fan is surging just a tiny bit. Hopefully it will stay running.
Moot & Moose, thanks for the suggestions. Earlier this evening, I called the two local TK dealers here in Minneapolis and one said they were busy for a few days, the other said they might get to it tomorrow but weren't sure.
I'd at least swing buy and pick up the glow plug socket tool if they have it - it should only be a couple of dollars. Once you remove the glowplug you should be able to see the vent hole and the carbon obstructing it. IIRC, it is on the bottom of the glowplug cavity (on a D2 heater)
It can't hurt to pull the glowplug and clean out any debris you find, as a partially clogged vent hole may hamper low heat operation, as well as startup.
When I was diagnosing mine Ray told me that sometimes the combustion chambers themselves will clog/carbon up and that there are a couple of solutions, depending on the severity of the problem:
1. Run some K-1 kerosene (which is much cleaner than diesel) thru the unit.
2. Complete unit teardown and disassembly for cleaning of carbon deposits inside the combustion chamber (which can become pretty much completely clogged with carbon)