Bushhog gearbox help

[pennwalk]

I started a thread about a John Deere LX4 bushog and realized that JD LX4 was a poor title.

I have the gear box off the deck and on the bench with the top off.
The rear bearing on the input shaft ground itself up. There is very little oil and a lot of metal flakes.

Can I clean up the bearings or should I replace them all?

How do I remove the rubber seals?

There is a heavy snap ring that holds the bevel gear in place on the input shaft. I now have 3 different snap ring pliers and none are heavy duty or open wide enough to remove the snap ring.

Where can I get a heavy duty snap ring plier?

Thanks
Chris

 

[LD1]

I started a thread about a John Deere LX4 bushog and realized that JD LX4 was a poor title.

I have the gear box off the deck and on the bench with the top off.
The rear bearing on the input shaft ground itself up. There is very little oil and a lot of metal flakes.

Can I clean up the bearings or should I replace them all? Replace them.

How do I remove the rubber seals? Assuming they are the lip style rubber seals, you can either get behind them with a punch, or use a seal puller. But plan on replacing them as well if you remove them.

There is a heavy snap ring that holds the bevel gear in place on the input shaft. I now have 3 different snap ring pliers and none are heavy duty or open wide enough to remove the snap ring.

Where can I get a heavy duty snap ring plier? Any tool suplier. Sears, NAPA, etc. Or you can order online any kind you want. MAC, Snap-on, etc.

Thanks
Chris

If you are going to rebuild this gearbox, make sure you disassemble everything and clean it out thouroughly. Nothing like throwing it back together and some metal grit/shavings find their way into your new bearings and destroy them as well.

 

[plumbstraight]

Most these gear boxes run on 90 140 gear oil. I found that keeping that bottom seal in very long is near impossible. I topped it off with grease and have not had any problems.

 

[easygo]

I had to replace the lower seal on my gear box just last year. I don't know if there is a better way but I pretty much had to destroy the old seal when I took it out. I took out the shaft and then carefully pried up on the inside of the seal. It is a very tight fit and the it was quite mangled by the time it came out. The upside was that I didn't scratch up the surface it was seated in.

I agree with LD1. You should clan out the gearbox the best you can so there are no metal shavings left in there. It's a good idea to frequently check the oil level as you now know. I remember reading a post when someone used a brand new bush hog or finish mower and forgot to fill the gear box with oil. It was shipped with no oil and he said it burned up inside of an hour.

 

[pennwalk]

I was afraid you would say to replace them but that's what i figured would be the right thing to do. Lately every time I talk to the JD parts guys it is a shocking experience. I mean $750 for a gear box.:confused2:

I have actually been to Sears, two good hardware stores and three auto parts stores. I was just saying to my wife that I don't know why I waste my time with local stores. I might as well go directly to the internet.

I do now have a very nice medium duty snap ring plier that will be a big improvement for all of my regular stuff. It just isn't strong enough for the gear box.

As far as the oil for the gear box goes if I get that far. Do you fill it with grease or just add some grease to the oil?

Thanks
Chris

 

[pennwalk]

I got this one from the dealer for parts. It had a bad gearbox. When I got it home I decided it was way too good to part out. My regular bushhog is a square KingKutter which I got used and have used for years. It has always worried me that it doesn't have safety chains. It is really astonishing how far my little 18 hp Yanmar can launch a football sized rock. I have to admit that I have only checked the oil on the Kingkutter once. I guess it's due.

Chris

 

[Chilly807]

You're better off to replace the bearings throughout, if there was contamination. Unlike a PHD gearbox, the rotary cutter gearbox gets continuous use, good bearings are a must.

An industrial supply store should have large snap ring pliers, they won't be cheap though. Gray and Proto make a good heavy-duty set.

Bearings should be easy to find, any bearing store should have them in stock. Mine were on the shelf for my PHD gearbox.

Take the shaft with you when you look for snap ring pliers, it'll give the sales folks a better idea what you need. Another option is to drop off the entire thing at a millwright/mechanical repair shop. They'll be cheaper than the dealer most times, just tell them what you want done and get a price before you agree to have them do it.

Sean

 

[LD1]

I was afraid you would say to replace them but that's what i figured would be the right thing to do. Lately every time I talk to the JD parts guys it is a shocking experience. I mean $750 for a gear box.:confused2:


As far as the oil for the gear box goes if I get that far. Do you fill it with grease or just add some grease to the oil?

Thanks
Chris

Dont go to JD. When you get it appart, there should be numbers on the bearings which can be easially cross-refrenced online. It is probabally just 4 tapered roller bearings. 2 on the input shaft and two on the output. Cross the numbers and stick to a quality brand like SKF or timken. Tapered rollers of the size range you probabally need will probabally be $20-$30 a peice. But once you cross the numbers, you can shop ANYWHERE online and get the best price you can.

But the output shaft seal you may need to go through JD for. Bushhog seals are typically a little different. They have a MUCH heavier metal housing.

As to the oil vs grease thing, do a search. You will get differing opinions, and several days worth of reading JUST on that subject. There is no doubt that oil lubricates much better than gears. and if you are rebuilding, it should not leak oil. The problem comes when you hit a fence or wire or something and rip the bottom seal up and you have no idea you did it. If you continue bushhogging without oil.......well, that ISNT better than grease, but it WAS while there was oil in there.

I have known farmers who buy a BRAND NEW BH and never put oil in it for this reason. They go straight for the grease. Others will wait until it starts leaking and then go with grease. And others never have a problem with oil. So it's really up to you. But if you do use grease, use the lightes weight you can get. Prefferabally a 00 weight grease.