Rotary Cutter - Gear Box Lubrication?

   / Rotary Cutter - Gear Box Lubrication? #11  
running 85/140 gear in mine. ensure the vent is working properly, & check underside for any gearbox seal leaks.
pull & sharpen the knives, many operators skip that step for good performance. while under there, check cond of stump jumper. if the hog works well, may consider a new set of knives, & of course, try to extract existing oil as you can, repsectfully
 
   / Rotary Cutter - Gear Box Lubrication? #13  
Went to use my Frontier RC60 a few weeks ago. Checked the oil in the gearbox and found that it was over the level plug by quite a bit, and very milky looking. Seals are good and it has never leaked. Just condensate I guess. Biggest challenge to draining it was getting it up on edge to drain the gearbox. Of course there were upper frame members in the way, so I had to hold the drain can under the gearbox while it drained. 90 weight gear lube takes it's own sweet time!
 
   / Rotary Cutter - Gear Box Lubrication? #15  
Get one of these vacuum pumps. I find mine to be an invaluable tool for draining whatever from a sump. I use it to change out brake fluid in a master cylinder, suck oil out of crankcases with no drain plug. Rotate out power steering fluid. Sometimes even brakes systems although not usually. :) You name it, if you can get the hose to the bottom you can suck liquids out.

I used mine on my RC a couple weeks ago as I have no drain plug. I doubt I got it all out but I got a lot and 75% exchange is better than 0% exchange.

HF used to carry them but I cannot find it there online now. Here is an Amazon unit:

 
   / Rotary Cutter - Gear Box Lubrication? #16  
You could run straight Motor Honey, STP, Extender.

Big trucks of the 18 wheel variety must be using fiber mesh synchronizers. Use ATF instead of gear oil. Gear oil will goof up fiber mesh. So, we fill with straight STP, because it's compatible with ATF. I know of a few that have over 5 million miles. Not many keep them that long, but the ones that do...When they get that old, engine and trans are good. Frame cracks and rear end spindles are a problem.
 
   / Rotary Cutter - Gear Box Lubrication? #17  
I've got a 6' rotary cutter that I've been putting straight grease in it for more than 20 years, it runs quiet and has never given even one minutes problem!

That's all it's going to get too.

SR
 
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   / Rotary Cutter - Gear Box Lubrication? #18  
I've got a 6' rotary cutter that I've been putting straight grease in it for more than 20 years, it runs quiet and has never given even one minutes problem!

That's all it's going to get too.

SR
Sawyer Rob, How do you tell just how much grease to put in? Since it won't bleed out of the - "full level" - hole? How many tubes of corn head grease is advised? Just pack it in to the top of the gearbox? Does grease not matter if the box is over-full? Thanks.
 
   / Rotary Cutter - Gear Box Lubrication? #19  
Sawyer Rob, How do you tell just how much grease to put in? Since it won't bleed out of the - "full level" - hole? How many tubes of corn head grease is advised? Just pack it in to the top of the gearbox? Does grease not matter if the box is over-full? Thanks.
On my cutters, the top unbolts very easily. I opened the box and put in two tubes of grease, then after a day I opened it again and looked to see how much is in there. That's how I got started to see what it needs.

You need enough just grease that it's getting everyware, shafts, bearings ect., that's all that's necessary.

SR
 
   / Rotary Cutter - Gear Box Lubrication? #20  
This video shows the difference between NLGI grade 2 and NLGI grade 0:
 
 
 
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