Spindle bearing failure - HELP!

[Jason Pallas]

I've been having a rather troublesome problem with bearing failure on my 48" Buntons. Seems that I'm constantly rebuilding the damm things. Sometimes they fail after just two weeks of cutting. I've done everthing I can think of - blades are balanced, greased regularly, etc... I've recently decided to give synthetic grease a shot - but at $5 a tube it's almost twice as expensive as the other stuff.
Does anyone have any advice? Any advice would be appreciated. These machines work a lot (we do about 475 lawns a week around here) but bearing failure after 2 weeks on a new rebuild is just too soon. I'm willing to try anything to keep from having to change another spindle on the road or after work. Much appreciated.

[AVRECON]

I'm not sure if they will fit, but I'd almost bet they would. Try Scagg or Bobcat spindles.

[lawnman_scott]

Is it the bearing in one particular spindle that goes, or is it in all of them?

[awm]

I know how much of the 475 yds that buntun does,
but i guess they could be just over heating and burning out.
get your men to lube every 6 hrs ,unless you decide to get an exmark

[racerdave]

Buy a new spindle. The spindle shaft in the spindle you are rebuilding may be slightly bent, causing premature failure of the bearing. Also, check with the Dealer to see if there is a bearing preload requirement for this spindle. If you have too much preload, the bearing will heat up, If you don't have enough preload, the bearing will skid instead of turn.
david

[Jason Pallas]

Thanks guys - some good ideas. It's not confined to one particular spindle. I'm pretty sure the shafts are all straight and relatively new. They all seem to fail equally. We could grease them more (every day). We grease them weekly now (it's such a pain because the grease fitting is underneath the mower - not like the new top greaseable spindles). I'm not sure if the scagg or bobcat spindles will fit - I defintely like the tappered roller bearings much better - however, I do recall looking into it and something wasn't compatible (bolt pattern, pulley diameter,etc....).
Racerdave - I'm not sure what you mean by preload. If you explain to me what preload is, maybe I could explore that avenue. Thanks.
One last thing that I read in a thread was belt tension - i.e if the belt tension is incorrect (too tight) this might cause the spindles to wobble - anyone have any experience with that? Thanks again -

[EROSS17]

475 lawns a week? How many crews do you have going? What part of the Detroit area? 475 is an incredible amount of lawns.

[racerdave]

Jason, bearing preload is a setting used when rebuilding spindles in general. I'm not sure if yours fits in this field but I'll still explain it. Bearing preload is a required function for all taper roller bearings or angualar contact bearings. The preload ensures that the bearing balls or rollers will "roll", if the preload is not enough, the bearing balls or rollers may actually skid around the races. Too much preload will cause them to overheat and fail. This load is measured where the bearing is captured, and should be around .001" to .002". You should check with your dealer or mower manufacturer for the right preloads and assembly sequence. Grease may also contribute to your problem, most bearing failures are a result of over lubrication. If there is too much grease in the bearing, the bearing will also tend to skid instead of roll. Hand pack a bearing then rotate the races in your hand, the grease thats pushed out of the bearing is excess lubrication. A little dab will do ya! so try using less grease. As far as belt tension goes, use the minimum amount of tension required to keep the belt fron slipping. check your owners manual for deflection requirements.
david

J, also make sure you are getting the right bearings. Get the bearing# from your owners manual, don't rely on the bearing # you just pulled out. Some are enterchangable, but they don't work the same. i.e. speed rating/load rating

[lawnboykb]

:confused: Do you balance your blades?

[John from OH]

Jason,

Do the new bearings have seals on both sides? If so, remove the seal on the side the goes in the spindle housing so that the bearing can get lubrication. The new bearings are often sealed on both sides and are supposed to need no furthur lubrication. Its a good theory, but they seldom hold up without additional lubrication.

[Eric ELM]

Every time my we had a bearing go out on the farm, my father would say, "It must of been over greased". BTW, that was a pun he had. You are not greasing it enough is my guess. How many shots to you pump in when you grease it once a week. My guess is, you are probably putting a good 40 hours a week on that machine. I grease mine every 25 hours and put in grease until it comes out. If you don't pump in enough for it to come out, it doesn't get up to the top bearing. We have had great luck with our spindle bearings, lubing this way. Some members say this isn't the way to do it, but I've replaced 1 set of bearings in the past 16 years and I put some hours on my machines. My oldest Chopper has 3,333 hours right now and this is the machine I replaced one spindle bearing set about 300 hours ago.

I'm not sure how many hours the guys that disagree with me on this are getting out of their spindles. Can someone tell me? Is it double, tripple, or more?

[Dillon]

I had the same problem with my Bunton, I now have 3 Scags & a Exmark and haven't replaced a bearing in 3 years.

[Jason Pallas]

Thanks for all the input. Racerdave - thanks, I think I understand preload better now. I'm going to follow some of your advice. I think that greasing the bearings more often - but with less grease may be the answer. Blades are all balanced and everything else has been checked and double checked for vibration/balance etc...
I've been getting the replacement bearings from J. Thomas Distrib. I'm going to switch to the Hi-Temp grease (had been using general purpose grease). I believe the J Thomas bearings are the right ones - Im trusting them. I wish they were tapered but they're not. I have been popping the inside seal - but that hasn't seemed to make a huge difference - yet.

Yeah 475 lawns a week is a B@#L Buster amount / 2 crews - lots of mechanic work after hours - but some really helpful advice from you guys on Lawnsite.com has helped me learn some new things - and I've been at this for 20+ years. THANKS! Your're never too old or too big to learn from others. I really appreciate the help.

Eross17 - We're over on the east side of Detroit / Grosse Ptes, Harper Woods, Saint Clair Shores Northeast Detroit.

[Mscotrid]

475 yards a week...Is this Wilt Chamberlin Lawn Care Company?

[mike]

USING GENERAL PURPOSE GREASE IS SOME OF YOUR PROBLEM. I SUGGEST ALWAYS USING HIGH TEMP. GREASE ONLY IN THE SPINDLES.
I ALWAYS USE THE BEST HIGH TEMP. GREASE I CAN FIND TO USE IN SPINDLES. I HAVEN'T EVER HAD TO REPLACE A SPINDLE. GOOD LUCK, HAVE A GOOD DAY!!!!

[TLS]

Use a high temp, disc brake compatable, brand name wheel bearing grease. Also, I believe that the Bunton's use a manually adjustable spindle belt tensioning system. DO NOT OVER TIGHTEN BELTS they should be almost loose when you deflect them with a finger. I made the mistake of keeping my belts too tight on my older SCAG's and blew quite a few bearings because of it! Side load will kill a bearing real quick! Are you wiping the zerks free of grass before greasing? Dirt in the housing will kill a bearing even quicker!

[eslawns]

Jason,

I have an Encore which has had a similar problem since I got it 6 years ago. I don't cut anywhere near that many lawns a week, but I was getting 3-4 months (max) from the bearings. I firmly believe that it is because Encore used Aluminum housings. When these fail, I will be replacing them with cast iron or steel housings. If yours are Aluminum also, this might be the problem. My other mower has this type of housing, and I haven't needed to replace them yet, and there is less play and vibration in them than in my Encore when I finish a rebuild. When you do find a solution, please post it here.

[TLS]

Racerdave may also have hit the nail on the head by saying the spindle shaft may be bent. Next time you replace bearings ( probably soon, right?) roll the spindle shaft across a smooth surface and look for any wobble. Just a little is all it takes to smoke a bearing a 3600 rpms +.

[deason]

I agree with Eric.

As a former Farmer myself, I believe in the saying "an ounce of prevention is worth a pound of parts". Unless the bearing is lubricated, it will not function properly. that my freind is simple logic. Like others have said, unless the bearing is running with pressure other than straight up and down, you shouldnt have a problem.
You mentioned greasing every 50 hrs. Try greasing every 8hrs or at the beginning of each day. My guess is that with the amount of yards that you are cutting each day, that bearing(s) is running 6 to 8 hrs non-stop. That gives trash and heat a good chance to eat away at the grease that is there. It may be a hassle to grease under the deck that often, but I would rather be greasing bearings than turning wrenches on them. As for types of grease, use a good Lithium grease. It tollerates the heat better.

[Jason Pallas]

Thanks all - got some great advice here from everyone and I and taking it all to heart. I've switched to the High Temp grease (found it at J Thomas for about $2.50 a tube - that's only about $.50 more than the general purpose stuff and about $3 cheaper than the synthetic grease at the auto parts store). Seems to be making a difference. The Aluminum housing thing is also a good lead - I've got them now and I think I might invest some time in tracking down steel ones. Thanks again!

[Lawn DOG]

If you are doing all the correct maintenance. My quess is it sounds like it maybe a manufactor defect. I've mowed alot of grass and never had to replace a spindle in 10 years. Good Luck.

[sdwally]

On some machines the OEM bearings are what you need to go with. They come as a matched set with spacers. If this is the case and you are just replacing bearings and not the spacers also, then your bearings will not be aligned properly. (2) If they are ball bearings try removing the bearing seal on inside of the bearing, most of the time ball bearing come with seals on both side, ie your bearing aren't getting any grease. (3) Check a repair manual, the bearing spindles might need to be torqued to a specific rating for preload. If this is not done you would experience premature bearing failure.

[Jason Pallas]

Interesting Update - I had a spindle housing break on our Bunton 52". This machine is about 4 years old and the spindles/bearings have shown no sign of wear/failure. At any rate, this gave me the opportunity to take apart the otherwise good spindle and see what was different about it (as opposed to the ones that had been failing). Here's what I found.

#1 The bearing is sealed into the housing with what appears to be a Perma-gasket seal. After the bearing is pressed in, it looks like the factory then seals the seams with a rubber gasket material - good idea to keep the dirt/dust out.

#2 There is an additional machine bushing (washer) between the snap ring and the bearing - I presume this also cuts down on the dirt/dust penetration of the bearing housing.

#3 On the bottom side, there is a rubber seal (to probably further prevent dirt/dust from entering the housing. Although this looks like it is manufactured, I think I may be able to make a similar functioning seal out of the gasket in a tube / permagasket material.

#4 Finally, I know that there has been a lot of discussion about greasing/over greasing bearings. I've always pulled the inner seal out of the bearings to allow better grease access. But, the concern is that overgreasing has the potential to force out the remaining outer seals. This spindle housing has a grease/zerk fitting but it also has a presuure release fitting on the other side. I knew this but hadn't mentioned it til now because I wanted to see how it works. It's a small spring loaded valve that will allow grease to flow out but then seals to prevent dirt from entering. INGENIOUS! This certainly eliminates the worry of over greasing/blowing out the seals. I've got to track these things down - but they appear to be about the cost of a zerk fitting and can easily be installed with a drill and a tap. In the absence, a small hole drilled in the housing to allow grease to escape when full may do the trick (but may also allow for the introduction of dirt into the housing too).

At any rate, I look forward to changing some of my spindle rebuild techniques/procedures based on these new discoveries. I hope my new findings benefit some of you guys that gave me some very appreciated advice and direction. Thanks again - I'll keep you posted on my quest find the perfect spindle!

[d&dlawnservice]

Question, How do you know if a spindle bearing has failed?

i have a 36" ferris that has been cutting unevenly, and it looks like there is a little play in one of the spindles. I was looking at replacing the whole spindle assembly, but I wonder if i only need to replace the bearing. Also, if I just change the bearing, do i need to press it into the spindle or does it just drop in there?

[Nosmo]

If a spindle bearing has gone bad you can probably tell by reaching under the deck and try giving the blade an up and down movement.
Any play up and down indicates a bad bearing.

Nosmo

[d&dlawnservice]

What about side to side motion?

[Runner]

Sometimes, you can get some side to side motion, but not ususlly. If there is side to side motion, that can be an indication of worn housing, too. Sometimes, when a spindle bearing goes bad, there will be noise and/or vibration. This is the most typical indicator. If you change it soon enough, the spindle housing itself stays o.k..

[marvinlee]

You might consider buying brand name bearings from SKF or other top line bearing makers. Also, on an old Gilson garden tractor, the tapered roller spindle bearings failed frequently. I replaced the bearings with sealed ball bearings and have had much better luck. Just recently, I rebuilt the entire deck and put in the latest sealed ball bearings with polyurea grease. These have a claimed life of 500 hours, and I hope for more. My theory on the tapered roller bearing failures is that the spindle shaft was flexing and putting excess pressure on the ends of the rollers. The Gilson spindle shaft is only three quarters of an inch.

On the Kubota ZD I use a synthetic grease only. My inventory is Chevron synthetic, but there are several other brands. The cost per tube is less by the case. Good luck on your spindle bearings.

[topsites]

Racerdave - I'm not sure what you mean by preload. If you explain to me what preload is, maybe I could explore that avenue. Thanks.
One last thing that I read in a thread was belt tension - i.e if the belt tension is incorrect (too tight) this might cause the spindles to wobble - anyone have any experience with that? Thanks again -

Pre-loading is to pack the bearing with grease BEFORE installation, this is an absolute requirement, don't tell me you stick them in there dry... You can get a special tool at the auto-parts store for this, looks like a small pyramid shape thing with a zirc on top - you slip the bearing in there and squeeze grease until it oozes out the sides, then it's packed. Costs about 10-15 dollars.

Far as synth grease, you can run synth TWICE as long before re-greasing, this makes up partial cost difference thou it still costs more. Also make sure you don't mix greases.

The only other thing I can think of is see about running the belt a bit looser, not much, but just a little less belt tension may help.

Now on my new wb's (toro proline 30197) the bearings are sealed but they fail after about 500 yards or in my case, every 2 years but these are maintenance FREE so this is normal (no grease, ever). The belt tension on these fixed decks is a trick, I'd say about as tight as an alternator belt on a car but then that's on MY cars, heh... Still, about an inch or so of play when you pull on it where there is a foot of space between pulleys.

On my OLD wb (toro proline 30165) the bearings are greased and it is a float deck with MUCH lower blade rpm - These have never failed me but the belt is a bit looser as well, since the things aren't flying at 3000 rpm, the belt is on there and it won't come off, but it has some slap to it when it's running. I'd say up to 2 inches of play in a 1-foot space between pulleys.

Either way, just try releasing a little bit of tension and see how it works. Then if it works great, leave it alone but if it still fails see if you can let go a little more - the looser the belt can be before the mower suffers, the better - Takes time to learn the trick to adjusting, best of luck.