Look at the tube. The material tends to swell, and then the filament ist blocked. Look also for the fan of the hot-end cooler. It might be blocked or worn.

Gentlemen, it started with fungus and a not very well written answer. I apologize for not showing the appropriate respect to Shakespeares language. But then the discussion went from fungus to racism and even further away from the topic. I can deal with getting a down-vote for a correct answer - our forums sometimes lack wisdom too. But if you continue like this, I will say " Macht doch Euren Dreck alleene" ( it might be very educating to find out about the origin of this sentence ) and leave this forum. Now say "peace and joy to the world" and make a suggestion to solve anjus problem. Best regards Klaus

Hi, I am sorry to say that but fungus in a microscope usually means the death of the microscope. You only Chance is to take it to parts immediately, clean all parts thoroughly and maybe the following might help : Hydrogen peroxide, or bleach, can be used to kill fungus. You might try 94% distilled water, 4% clear ammonia (for cleansing) and 2% hydrogen peroxide Or look for Fungus Cleaning Agent from Carl Zeiss "Fungusreiniger NEU". INR 0117.362 Good luck !

Versuch` es mal beim Autolackierer. Die haben oft Farbmessgeräte um Lack zur Ausbesserung kleiner Schäden herzustellen. Oder frag mal beim nächsten Standox-Depot. Die können auch kleine Mengen genau anrühren. Viel Erfolg !

no. The motors need different amounts of air and burn different amounts of fuel. The motor might run at low speed but will die at higher power demand. best regards

Oldturkey is right, but before youdo that, look at your floater valve inside the carburetor if it is stuck the fuel level is wrong and the engine tends to race.. good luck

Noah is right. Another possibility is degraded oil and more probable, a worn oil pump. ( a tooth wheel pump ) Change the oil and look carefully for metal-chips. Check ( by taking it to pieces ) your oil pump then! Good luck !

very often you find a broken solder-connection close to te receptacle. It can easily be resoldered. You might try some cleaner before, maybe there is just a bit of dirt inside.

There is a shock absorber that should keep the drum from moving too much. Can you check it ? Try moving the drum up and down. Does it swing long ?

Do you hear the noise when you turn the drum by hand ? Try moving it backwards, sometimes things get between drum and sealing. You might be lucky and the thing might fall out. Good luck !