Buying used flail mower (JD or Ford)

[pripyat]

I ran the mower a bit and then sucked the oil out the gearbox. It look pretty bad. I put some cheap gear oil back in it since I'm going to swap it again in another couple hours.

I'm noticing that there are no grease fittings for the rotor that has the cutters attached. Is there any reason to lubricate this or is this even possible?

 

[Industrial Toys]

There certainly should be. I can't see it being a sealed bearing. Did the zerks get broken off?

 

[pripyat]

I don't see anything and it isn't mentioned here:
OMP70756

 

[kthompson]

The one thing I was going to recommend for you was be sure you keep cutter rotor grease well for those rotors are turning some very high rpms. Think about the tip speed needed for good cutting. Now on a rough cut single spindle mower their spindle has the blade tip out there say two feet. The flail mower has it blade tip out there say...8 inches? The flail mower rotor is really got to turn much higher rpms and if there is no grease fittings for it would surprise me greatly. Look very carefully for on the flail mowers I have had and have now the grease fitting is often protected or maybe hidden by braces and even rubber plugs to protect them. You need to be sure you are using grease recommended for again a flail mower rotor is flying compared to a rotary mower. This is also reason you need to replace worn flails all at one time.

Congratulations on the mower, for brush cutting I think a rotary mower will cut faster but a flail mower will mulch it where the rotary mower will not and if you are not aware a flail mower will not throw objects like a rotary mower will, much safer. One reason they are used for road cutting in some areas. Flail mower is not as likely to leave sharp stubble either as a rotary mower. The one area where a flail is not a good is using on a lawn and making tight turns if rear roller is on the ground.

 

[Industrial Toys]

Rather then just looking for zerks on a machine, it's easier if you know how the machine works and then will often know where there should be zerks. Sometimes idlers have sealed bearings but usually the bearings doing the work will have zerks.

 

[def38]

BTW, the flail rotor is not a high speed application. Most turn at about 5X PTO RPM. Typical bearing sizes used in the rotor are rated at 10,000RPM. Also load specs are more than adequate for this application. But, they do need grease from time to time. Don't over grease or you may force out the bearing shields if so equipped. Use a Lithium soaped grease of NLGI II grade. Avoid Calcium soaped greases inasmuch as they will wash out more easily when in contact with water. Marine grease while more costly is a good choice.

 

[CADplans]

BTW, the flail rotor is not a high speed application.
But, they do need grease from time to time.

I have owned my 390 since it was new sitting on the dealers lot,,
There never has been a grease fitting on the rotor bearings,,

There is a grease fitting on the roller bearings,, I think that has grease fittings, because bearings HATE to turn super slow,,

You can see the roller bearing grease fitting in this pic,,

 

[Hay Dude]

Mine is in the yellow circle

 

[Industrial Toys]

Nice tractor/mower combo.

I think that a poor choice of Deere not to put greasable bearings on the Rotor.

 

[pripyat]

I just did some digging, it is true that the rotor bearings are not greasable.

The bearing is part number JD9275 which cross references to TIMKEN 1106KRRB5. Cross Reference Chart



Here is a PDF on the design of the bearings. It is recommended to not grease them.

https://www.paramountindustrialproducts.com/pdf/1/101.pdf

In other news I mentioned previously that I suctioned the old gearbox oil out and replaced it with new. It was pretty nasty.



The oil in the tubing pictured below was run in the gearbox for an hour and was still quite hot. I replaced the gearbox with new fluid afterwards.



I'll likely run this second batch of oil at least a couple hours before I switch over to synthetic.