60" MMM concerns

drumguy_01 · May 31, 2011

Hello everyone...hoping someone can ease my nerves about my 60" MMM.

I performed the 300 hour maintenance on my BX2350 last week, decided it was a fine time to take the mower deck off, sharpen the blades, grease the deck and clean the bottom of the deck.

I turned the deck up-side down to clean the bottom of the deck...no problems, put the deck back on the BX and stowed it away in the barn until this past weekend.

Pulled the BX out of the barn this past Saturday to mow and was happy to see no oil leaks under the tractor after the service.

I proceeded to mow my 2 acres, I noticed the smell of burning oil while mowing, didn't think much about it...figured some oil was burning off the block from changing the engine oil filter.

Sunday I needed to do some yard work so I backed the BX out and there was a pool of fluid on the barn floor....I took the mower deck off the BX, the fluid was coming from the gear box on the 60" MMM. I couldn't figure out why it would've leaked unless the drain plug was a little loose. I topped off the fluid then tightened the drain, inspection and fill plugs.

Why do you guys think the oil leaked out? Do I have any concerns? I don't think the oil would leak out of anywhere else besides the drain & inspections plugs. I'm planning on mowing again Friday, I'll be able to see if the leak is still occurring at that time.

I'd appreciated any ideas.

Sorry for the long post.

Thanks!!

RussMan · May 31, 2011

I can't imagine why it would leak unless the gear box has a crack in it somehow. But given the location of the gearbox, it would be hard to imagine something hitting it hard enough to crack it.

drumguy_01 · May 31, 2011

The gear box didn't appear cracked....I think it would be pretty hard to crack regardless, it appears to be solid cast. Plus, when you turn the deck up-side down, I think the deck balancing bolts hit the ground before the gear box, protecting it in a way.

Thanks for the reply.

RussMan · May 31, 2011

I can't imagine why it would leak unless the gear box has a crack in it somehow. But given the location of the gearbox, it would be hard to imagine something hitting it hard enough to crack it.

EE_Bota · May 31, 2011

My deck has a breather like plug on the top. I think it is sintered material. It could be that somehow that got clogged during the flip, and now air pressure builds testing the seals. That would be my thinking and my checking.

drumguy_01 · May 31, 2011

Ahh...I wondered what the extra plug was on top of the gear box...I'll check it out this evening, maybe I can back it out and clean it? Thanks for the tip.

bilrus61 · May 31, 2011

The oil gets hot and expands. If you overfill it by a little bit it will expand and find a way out either through the plug or the seals. The pressure is very high. I would wipe it off and keep a eye on the oil level. You can't "fill it up" to the top. If you did that oil you seeing/smelling is the natural result of a overflow from the normal heat inside the gearbox.

drumguy_01 · May 31, 2011

bilrus61 said:
You can't "fill it up" to the top.

I didn't "fill it up", I fill the gear box until it came out of the inspection plug, as the manual states.

I didn't change/add fluid to the gear box during the 300 hr service, I simply cleaned the deck, sharpened blades and greased the deck. The gear box fluid level hadn't changed, and I had previously mowed with no fluid leaks....that's why I'm puzzled by the leak I have now.

EE_Bota · Jun 1, 2011

What times I have ever done work under the deck, I use my FEL to hold the deck vertical, but canted back a little so if the loader fell, or the chain broke, it would very likely go the other way (away from me.) I choose the side to chain bases on keeping that vent above oil level.

drumguy_01 · Jun 9, 2011

Update on the situation....mowed this weekend and the gear box was still leaking.

Pulled the gear box off the deck last night, dropped the gear box off at the dealer this morning to get serviced....hoping it's just the bottom seal.