Brush hog gearbox...oil or grease?

[SPYDERLK]

i normally wait till the seals leak.. but yeah.. a nlgi 0# or 00# ep grease would be the ticket.

soundguy

Thats needed if youre doing light cutting. If you do frequent heavier cutting like trees that shake the cutter around a bit you can get by with nlgi 2. TSC store brand moves around pretty easy and works well if the cutter is banged around a little. Run it smooth tho and you need the lighter grease or things will get a little dry.
larry

 

[Soundguy]

Thats needed if youre doing light cutting. If you do frequent heavier cutting like trees that shake the cutter around a bit you can get by with nlgi 2. TSC store brand moves around pretty easy and works well if the cutter is banged around a little. Run it smooth tho and you need the lighter grease or things will get a little dry.
larry

if you pack it near full with the nlgi2, and then add a ounce or 3 of hub oil or 85-140 it would probably keep it all loose and non cavitated even at moderate mowing levels..

just have to make sure you are getting an EP product..

soundguy

 

[stackingstones]

what brand names are there for, or stores carry the 0# or 00# grease

 

[Soundguy]

was that a question or statement? it's unclear.

JD makes a 0# polyurea ep grease and usually stocks it , or can order it at a parts counter.

was that what you were asking?

soundguy

 

[Short Game]

I bought a used Bush Hog ATH-720 grooming mower that popped the lower seal after a couple of seasons of weekly 40 mile mows. It dumped all that 90 weight into the belt case and made a big mess. I pressure washed it and tore down the gearbox and resealed it. I suspect that I missed that the oil had been watered through the fill cap vent to the point where it could foam and then, blow out the seal. With perhaps a quart of air space above the oil, you can bet it's not condensation. If your oil is watered, bet its leaking in the vent hole. (You'd think Bush Hog would figure this out.)

Anyway, after all that work, I'd discovered my oil had emulsified again and I finally figured it out. I have no equipment sheds and so, the mower must sit out in the off season. I've learned to put a can over the fill and keep a weight on the can.

It bothers me that the only way to completely drain the gearbox is to invert the damned thing. So, even changing out the oil is a pain. If that seal fails again, I'll probably go with the grease. Glad to have found this thread.

 

[MHarryE]

When I worked for a major ag manufacturer, we wanted to run gear oil in our new corn head gearbox. Problem - oil kept leaking from the snapping roll shaft seals even though we did not find a seal wear problem. At wits end we checked to see what our largest competitor did in the same application. Turns out they filled their gear boxes with grease. It turned out it had to be a specific grease. We tried similar grease and it also leaked out (yes, hot grease does get runny, and a corn head gearbox takes a lot of power). We analyzed the competitor's grease and had our supplier give us the same thing. Problem resolved. Somebody had that answer in an earlier post - John Deere cornhead gearbox grease. That was 20 years ago but I wouldn't hesitate to use it in any Bush Hog type cutter.

 

[eastexan]

When I worked for a major ag manufacturer, we wanted to run gear oil in our new corn head gearbox. Problem - oil kept leaking from the snapping roll shaft seals even though we did not find a seal wear problem. At wits end we checked to see what our largest competitor did in the same application. Turns out they filled their gear boxes with grease. It turned out it had to be a specific grease. We tried similar grease and it also leaked out (yes, hot grease does get runny, and a corn head gearbox takes a lot of power). We analyzed the competitor's grease and had our supplier give us the same thing. Problem resolved. Somebody had that answer in an earlier post - John Deere cornhead gearbox grease. That was 20 years ago but I wouldn't hesitate to use it in any Bush Hog type cutter.

Very interesting info. Pretty much answers everything.
Thanks.

 

[Short Game]

Maybe I should change now, before the seal goes out again. I never want that mess or to do that job again.

Funny, I was using my mower since my post this morning and it tossed the belt. I found that the nut had backed off the tensioner spring. It's always something.

One of Murphy's Laws is: "Play with something long enough and you'll break it."

 

[Soundguy]

suction tube will get it out.

I like the vent plugs with a lil cap on tem.. but they will still get water in them in a hard rain..

bucket helps..

soundguy

I bought a used Bush Hog ATH-720 grooming mower that popped the lower seal after a couple of seasons of weekly 40 mile mows. It dumped all that 90 weight into the belt case and made a big mess. I pressure washed it and tore down the gearbox and resealed it. I suspect that I missed that the oil had been watered through the fill cap vent to the point where it could foam and then, blow out the seal. With perhaps a quart of air space above the oil, you can bet it's not condensation. If your oil is watered, bet its leaking in the vent hole. (You'd think Bush Hog would figure this out.)

Anyway, after all that work, I'd discovered my oil had emulsified again and I finally figured it out. I have no equipment sheds and so, the mower must sit out in the off season. I've learned to put a can over the fill and keep a weight on the can.

It bothers me that the only way to completely drain the gearbox is to invert the damned thing. So, even changing out the oil is a pain. If that seal fails again, I'll probably go with the grease. Glad to have found this thread.

 

[belah]

I once had a friend who put grease into the axles on his Jeep after draining out the oil. he said it kept water out better than oil. We run our 4wd vehicles in a lot of water here in Louisiana. Needless to say, the Jeep ran for about 2 days (about 15-20 miles) before the gears in the axles "Locked Up". He had to replace all the gears,bearings, seals etc. in both axles. He wasn't pleased!!!! So, I'd put 90 weight gear oil in the gear box and if the seals are leaking, replace the seals. It's a lot cheaper !!!!