# "Too Much Lubrication" ?



## Vol (Jul 5, 2009)

Dan Anderson on "Too Much Lubrication"....

Regards, MIke

http://www.agweb.com/blog/in_the_shop/


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## kyfred (Dec 23, 2009)

We just rebuilt a NH256 hayrake. Everything in the gearbox was wore. The dealer said to use No.2 grease to refill the gearbox instead of differential oil. They said to fill the gearbox. My brother in law who is a mechanic said that really goes against his grain that filling the gearbox like they said would hold heat. He said the gearbox needed a air space to help the heat dissapate. I guess he is on the same page as the guy in your article. Vol. 
Thanks for the article. At least I know someone else doesn't agree with filling something up with grease or oil . 
kyfred


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## slowzuki (Mar 8, 2011)

Nonsense, the more fluid touching the case the higher the heat transfer rate. The problem is overfilled gearboxes are generating more heat from the gears stirring the lubricant around. Windage losses.

Grease can work well in a gear box, the NH spec changed from oil to grease sometime ago. Grease thins out to oil like consistency once operating, but if its too thick it won't flow into certain kinds of bearings. The other problem is the wrong type of grease that isn't meant for this use will have additives that won't work well. There are lots of types of grease.


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## mlappin (Jun 25, 2009)

gotta agree with fluid having better heat transfer characteristics than air.

High speed bearings as well can be over greased. Most of those in the manuals when they say 1 shot every ten hours or something similar mean exactly that.


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