Do not fail to remember to re-seal the gearbox with RTV following you have discovered the appropriate blend. Even however they're known as "gaskets", they will not likely seal your gearbox on their possess.
If every thing appears regular, attempt changing the gear-mesh. This is accomplished with the mylar "gaskets" that sit among the 
primary gearbox situation and the enter/output caps. Attempt including or eliminating some of these spacers until finally your gears have approximately one/8"-1/four" of free of charge enjoy. Experts can get replacements ($1-two) in varying thicknesses, but we advocate the fast and soiled technique of slicing your personal out of a sheet of mylar.
"Groaning", "creaking", or "popping" all seem type-of related over-the-mobile phone. The ideal factor to do is to disassemble your gearbox and get a appear at the gears and bearings. The situation will normally existing alone in the way of damaged/lacking gear tooth, toasted gears (like that photo on our residence web page), or blown bearings.
My Gearbox is Groaning/Creaking:
Fortunate for you, we did a compose-up on our site. It is referred to as "How to alter the enter shaft on your rotary cutter gearbox".
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