Savagecommander says "airleak". Sure sounds like it. Especially if you are going through glowplugs.

Burning up glowplugs is usually from running too lean. Even though you ahve the needles set where they tell you, if air is leaking in, your air/fuel ratio may be too lean. Normal spot fopr a leak is around the carb where it installs into the crankcase. Carefully put some RTV (rtecommended is the oxygen sensor safe stuff) around the carb where it will meet the crankcase. Also dab some RTV both sides of the pinch bolt.

Engines can run quite hot until they are broken in, although generally it is a result of incorrect tuning. Turn counting is not much help other than getting it to run at factory specs. I'm not sure about your engine, but I've had engines that were runnning too lean at WOT and the HSN set around 4 turns. Typcially it's more like 2.5 though. You may want to try richening up the needles to see what happens.

Another problem may be your idle stop screw is set too high. Engine idles too high, clutch is grabbing...wheels won't turn as vehicle is held down for starting.....engine heats up. Easy check.....if you hold your vehicle off the floor with the engine running, do the wheels turn?