No need to service?

BTBO

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I have a Liberty Z 48" that has proven to be trouble free at least to this point. But having it for three years now with only 98 hours of use, I guess that is not uncommon. I know of the 6 grease points that I attend to at the start of each season, but noticed there aren't any zerks on the spindles, which I believe means the bearings are sealed. Is there reason to feel that I need not worry about the spindles, or perhaps is there something I can do to prolong the life of them?
 

bertsmobile1

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Unless the spindle sits on tapered rollers like they really should or has grease nipples then there is nothing the owner can do apart from regularly checking the blades for see-saw type of movement indicating that the bearings are worn out .
Because the bearings are pressed in you have to pull them out to check them
The act of pulling the bearings wears the housings so the bearing will not be held as tight and eventually the housing becomes too loose and allows the bearings to spin in the housing at which time the housing gets replaced
Where possible I fit grease nipples to all spindle housings and then use a "Z" ( single metal shield ) bearing on the top
These are not sealed like the the 2RS bearings used by mower companies ( because they are cheap ) so when greased the air & excess grease can ooze out past the shield .

Now in your case.
If you are only doing 30 ish hours a year and your bearings have stood up to 3 years with no problems then it is probably not worth worrying about
In practice most spindle housing will go at least 6 bearing replacements before they become worn too much to hold the bearing outer race tight thus needing replacement.
However most will have worn thin around the lower bearing housing from stuff getting caught there and slowly polishing the metal away .
So working off those number 3 x 6 = 18 years by which time the mower will be on it's last legs any way
If you get 4 years out of the bearings then you are looking at 24 years
About the only thing you should do is regularly remove the blades . clean the debris that is wrapped around the spindle & blade away then sharpen & balance the blades
Replacing the blades regularly prevents the fastener self tightening so much that they have to be cut off
 

BTBO

Active Member
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Unless the spindle sits on tapered rollers like they really should or has grease nipples then there is nothing the owner can do apart from regularly checking the blades for see-saw type of movement indicating that the bearings are worn out .
Because the bearings are pressed in you have to pull them out to check them
The act of pulling the bearings wears the housings so the bearing will not be held as tight and eventually the housing becomes too loose and allows the bearings to spin in the housing at which time the housing gets replaced
Where possible I fit grease nipples to all spindle housings and then use a "Z" ( single metal shield ) bearing on the top
These are not sealed like the the 2RS bearings used by mower companies ( because they are cheap ) so when greased the air & excess grease can ooze out past the shield .

Now in your case.
If you are only doing 30 ish hours a year and your bearings have stood up to 3 years with no problems then it is probably not worth worrying about
In practice most spindle housing will go at least 6 bearing replacements before they become worn too much to hold the bearing outer race tight thus needing replacement.
However most will have worn thin around the lower bearing housing from stuff getting caught there and slowly polishing the metal away .
So working off those number 3 x 6 = 18 years by which time the mower will be on it's last legs any way
If you get 4 years out of the bearings then you are looking at 24 years
About the only thing you should do is regularly remove the blades . clean the debris that is wrapped around the spindle & blade away then sharpen & balance the blades
Replacing the blades regularly prevents the fastener self tightening so much that they have to be cut off
Thanks for the in-depth reply. I do remove the blades before cutting season, scrub off anything stuck to them, then balance using my $150 Magna-Matic balancer. Yes, I had to think twice about spending that much on a blade balancer. But considering the cost of a new spindle, I felt it was worth the exorbitant cost. It is so sensitive that after the blades are "perfectly balanced," I had put a small piece of tape (3/8" square) on the tip of one side of the blade----and as expected, that was enough to throw it off balance. Before cutting the grass, I make it a point to pick up any branches or twigs thicker than a pencil. I have no rocks or tree roots to be concerned about hitting, so grass is the only thing the blades see. I will use the see-saw method you mention to check for bearing wear. As far as the fastener self-tightening too much, I used anti sieze on the bolt threads then use a torque wrench to the specified lbs/ft value.
 

bertsmobile1

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Well that explains why your spindle bearings are still in good order
Balance is everything
Please stop using the anti-sieze on the blade bolts as it makes the self tightening worse.
You have gotten away with it probably due to the low hours of use
Also torque figures are usually for dry, clean , new threads
Lubricated threads are anything up to 20% lower torque to get the same tensile stress in the bolt
 

BTBO

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Well that explains why your spindle bearings are still in good order
Balance is everything
Please stop using the anti-sieze on the blade bolts as it makes the self tightening worse.
You have gotten away with it probably due to the low hours of use
Also torque figures are usually for dry, clean , new threads
Lubricated threads are anything up to 20% lower torque to get the same tensile stress in the bolt
I'll take your recommendation about the anti-seize under advisement.
 

7394

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I do remove the blades before cutting season, scrub off anything stuck to them, then balance
For my blades, when I remove them, I put them in a small drain pan w/water & after 15 minutes soaking or so, I can quickly wipe off the grass build up, & move on to sharpening & balancing..

I have 48 LZ as well.. Solid machine. & am enjoying it .
 
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