edbee Posted August 1, 2006 Posted August 1, 2006 Howdy, In the process of removing a little surface rust from Sunstar mower deck, which lead to the decsion to paint the deck, which lead to more disassembly, etc... Since I've gone this far, I might as well remove the spindles, paint them, check the bearings..... Bearings seemed fine. After removing the spindles, I discovered that the bearings are sealed! The bearings are Fafnir # P204RR6, which are a very common lawn mower spindle bearing. Very interesting, a single grease fitting per spindle, located between two sealed bearings! Knowing this, it seems to me the only advantge to periodically greasing these spindles is to keep the spindle cavity filled with grease, to prevent dirt, water, and grass from getting into the spindle. Any thoughts? edbee
MadMike Posted August 1, 2006 Posted August 1, 2006 edbee, The older deck that came with my tractor had grease fittings on the spindle housings, the newer deck I bought to rebuild did not. I also noticed that the bearings are sealed, so I called Simplicity to ask. I was told that the grease has two uses, one to keep moisture out of the housing and two to help dissipate heat. He said grease fittings came and went over the years based on consumer responses. Since my newer deck didn't have the fittings I was advised to pack the housing 1/2 to 2/3's full of high temp grease when installing the bearings. So far so good. Mike
Guest Posted August 1, 2006 Posted August 1, 2006 I recently had a discussion on this with a club member and he explained to me how sealed bearings worked; point was a sealed bearing is SEALED and nothing should get in there. I asked, can't some of the grease work it's way in, he answered... No. The high temp grease point is interesting.
Mith Posted August 1, 2006 Posted August 1, 2006 Could they be only sealed on the outside like the ones on my WheelHorse deck. Grease can still get in from the inside, but the seals on the outside stop anything else getting in.
Guest Posted August 1, 2006 Posted August 1, 2006 quote:Originally posted by Mith Could they be only sealed on the outside like the ones on my WheelHorse deck. Grease can still get in from the inside, but the seals on the outside stop anything else getting in. Actually that was thrown out as an option in the discussion I was having... not sure how you do that... can you take off the seal without damaging the bearing... was that what was done on a deck?
PatRarick Posted August 1, 2006 Posted August 1, 2006 quote:Originally posted by michaelg221 quote:Originally posted by Mith Could they be only sealed on the outside like the ones on my WheelHorse deck. Grease can still get in from the inside, but the seals on the outside stop anything else getting in. Actually that was thrown out as an option in the discussion I was having... not sure how you do that... can you take off the seal without damaging the bearing... was that what was done on a deck? The seals can be easily removed without damaging the bearing. I used to remove the inside seals, thinking that it would increase the life of the bearings if they could be greased. I no longer remove the seals as I saw no significant difference in the life of the sealed or greased bearings. Only once did I see it as an advantage, as I was able to finish a job when a bearing got noisy and I was able to grease it. Pat
edbee Posted August 1, 2006 Author Posted August 1, 2006 I think Mad Mike has it nailed, back in the good ole days....when men were men, women were men, and sheep were just plain nervous! People took pride in periodic maintenance, now who misses greasing the steering linkage on their cars or trucks? With the advent of better grease and better seals, no doubt grease fitting were seen as an unneccessary expense that the customers didn't want. I initially thought the same thing Mith, that the side of the bearing facing the grease fitting would be open to receive grease (bearings only sealed on one side are common), but that is not the case. Thanks for the info Pat, I was considering doing the same, but I think I will pass. Thanks to all of you who posted. Ed
stevenj Posted August 1, 2006 Posted August 1, 2006 Generally, if you removed the inner seals from the upper and lower bearings and then filled the cavity with grease, you would stand a good chance of pushing the outer seal out of the bearing. You can build pressure with a grease gun a lot faster than the seal lips can purge and vent. If you pushed the seal out it won't be long before the bearing is toast, not to mention all the grease you'd have to clean up.
Al Posted August 2, 2006 Posted August 2, 2006 Hi, My first tractor a Wards Squire 10, (Landlord) came with bearings sealed on one side and grease fittings. The bearings seemed to last forever. Later Simplicity stopped putting grease fittings in the arbors and put double sealed brgs in. They continued this way even to the change to the new style arbors. Then they started putting fittings in again. I accused them of a "marketing ploy." The said it really helps. I didn't believe it, but came convinced after a few years. It seems that when the half sealed bearings were used they lasted forever if the owners diddn't over grease. The problem was "if a little is good, a lot should be better" people would pump a bunch of grease in them every time they mowed. This would push the seals out and all the grease would run out the bottom or up under the deck covers and grease the belt. The fix was no fittings and double sealed bearings, which didn't last as long as the half sealed bearings when properly greased, but lasted better that when they were over greased. Greatly reduced warranty claims. Seemed to be the best overall situation. Then came the new 2 piece arbors and often water would get in them where the pieces joined. Bearing life seemed to shorten. Them came silastic between the pieces when assembling. Helped, but grass juice and water would get in the seam and the paint would come looe and the water would get in when people washed the deeck or it rained and the tractor sat out. Next the grease fittings added. When the arbors were assembled at the factory they started putting about a golf ball sized ball of grease in them on asssembly. This kept the water from working its way into the bearings past the seals. As people grease them they just add a little grease to the housing. As was stated above the grease protects from water and transfers some heat. If the new arbors are "OVWEGREASED" to the point the cavity is full, it will push the inner seals into the bearing races and cause failure and will force the housing apart distorting the housings and the grease will come out on the deck. When we put the new arbors together we put in about half a cup of grease in and seal the 2 halves with a ring of silicone around the inside of the bolt circle. We tell people that buy a new unit that a few pumps of grease once a year is adequate. Al Eden
HubbardRA Posted August 2, 2006 Posted August 2, 2006 If you want to remove the inner seals so that you can lube the bearings, you can drill a small hole (about 1/16) into the arbor cavity just below the top bearing. This will act as a pressure relief, and if you pump the grease gun slowly, so as not to produce a sudden pressurization, will prevent seal damage. As the grease extrudes out thru the hole, it will seal the hole to dirt and water. Just remember to clean the hole with a small drill bit or nail prior to putting more grease into the arbor.
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