Will not forget to re-seal the gearbox with RTV right after you have found the correct blend. Even however they're known as “gaskets”, they won't seal your gearbox on their very own.
If almost everything appears normal, consider adjusting the gear-mesh. This is done with the 
mylar “gaskets” that sit between the major gearbox scenario and the input/output caps. Attempt incorporating or taking away some of these spacers until finally your 
gears have about one/eight”-1/4″ of cost-free enjoy. Professionals can order replacements ($one-2) in various thicknesses, but we advise the rapid and filthy strategy of cutting your very own out of a sheet of mylar.
“Groaning”, “creaking”, or “popping” all audio sort-of equivalent above-the-cellphone. The best thing to do is to disassemble your gearbox and consider a seem at the gears and bearings. The issue will usually current by itself in the way of damaged/missing equipment teeth, toasted gears (like that photo on our property web page), or blown bearings.
My Gearbox is Groaning/Creaking: