Finish mower belt problem

[tanner]

I have a 48" LMC finish mower that came with my Yanmar 1500. It is about 9 months old and has worked great until about a month ago when I cut a 2 acre pasture for the first time this season. The right side belt came off while cutting, so I replaced both belts. Everything worked great for the next cut. Then yesterday, the right side belt came off again. I replaced it and it came off within 10 minutes of use. The pulleys look fine and everything seems to be in alignment. Any ideas on the cause of this problem?

 

[Mosey]

Have you checked the tension?

 

[tanner]

Danny, thanks for the reply. I thought about the tension, however, it doesn't seem to matter. When I first replaced the belt yesterday, I tightened it as tight as possible. The second time I installed the belt, I backed off the tension thinking it may be too tight. Of course, it still came off. The tension adjustment is for both belts and I'm not having any problems with the left belt. How tight should it be? Is there an accurate way to "measure" tension or is it simply a "feel' thing?

 

[Dozernut]

Check your spindle bearings. It sound like you have play in a spindle shaft. When the blade on the shaft, with the bad bearings, loads up it tilts a little, allowing the belt to slip off the pulleys. You should be able to match up the numbers on the bearings and buy locally at a good parts store.

 

[tanner]

OK, I'm going to ask a stupid question! Is the spindle shaft the shaft that the pulley is mounted to? Will I be able to feel movement in the shaft if the bearings are bad? Thanks!

 

[Bird]

I don't think Dozernut is still online, so . . ., Yes, to both questions.

 

[tanner]

thanks; I'll take a look at the shaft and bearings

 

[Dozernut]

Yes, the spindle shaft is the shaft your pulleys and mower blades are attached to. This is the same shaft that you have a grease zerk on, that you shoot grease into for the bearings. You have to take all of the belt guards off and expose the spindle housing. These will be held to the mower body by 3-4 bolts. These do not need to be removed unless the housing is cracked and will need replaced. Remove the nut, holding the pulleys on and remove the pulleys ( you might need a puller). You should have a exploded diagram showing all the bearing parts and the order they go in the housing. If you are handy with tools this is not a terribly hard job, but if you are unsure contact your dealer for help. There are no stupid questions, just the ones unasked!

 

[tanner]

I checked the spindle shaft and there does not appear to be excessive movement (in fact, there is very little movement) either up and down or side to side. Other ideas? BTW - I agree fully about unasked questions being the only stupid ones!

 

[bubenberg]

turn the blade slowly, very slowly, (by hand) and put one finger on top of the spindle, if you feel a kind of slight knock you have a spindle problem. repeat that for each spindle.

 

[Dozernut]

bubenburg said it all, follow his instructions. Thanks Bird for answering for me! I have been trying to unplug a downspout in between rains. Wished you had some of this H2O, we've had plenty and from the looks of the sky, more is on the way.

 

[Bird]

<font color=blue>Wished you had some of this H2O</font color=blue>

Me, too! On the TV news tonight, they were talking about the flooding and the fact that Dallas has already had over 20" of rain this year, and here I am 60 miles south of them and have only gotten 6.07" all year./w3tcompact/icons/frown.gif

And to make matters worse, I discovered today that I have too much water one place; the water heater has a slow drip that has apparently been doing it long enough that I'm not only going to have to replace the water heater, but also a section of flooring./w3tcompact/icons/frown.gif

 

[Steve_in_Ont]

While you're spinning the shaft (checking the bearings), also confirm that the pulleys are running straight and true... When you turn the shaft, the edges and groove of the pulley should not move up and down or side to side. Make certain that you check all of the pulleys, even any tension pulley.

And one other thing... I hate to ask, (but keeping with that only dump question thing...). Are you certain that the belts are installed correctly? Any tension pulleys should only touch the belt on the unloaded side of the belt. From the drive (PTO) pulley, the belt should travel to the driven (blade) pulley, then on to any tension system, then back to the drive pulley.

 

[rlk]

Bird, this is exactly why when I build or remodel a house, I never, ever, put a water heater inside the house. Putting it in the crawl space, or in an attached utility room, or garage makes a lot more sense.

On new houses in this area, they are actually putting water heaters in the attic. Even though they are sitting in a drip pan, I have seen many of the drip pan drains plugged with insulation. So when the water heater leaks (and they are all going to leak eventually) the drip pan will fill up, and the ceiling will get wet. With sheet rock ceilings it does not take much water before the entire ceiling has to be replaced. Saw one house where a plumbing fitting on a water heater in the attic cracked and water ran for about a week while the owners were on vacation. All the ceilings in the house, as well as the carpet and hardwood floors had to be replaced. If the builder had put the water heater in the crawl space, storage room or garage this would not have resulted in much if any damage.

O.K., I'm off my soap box now.

Bob

 

[Bird]

Yeah, Bob, they really do some dumb things when they build houses at times. My water heater has a drip pan, but it isn't big enough./w3tcompact/icons/frown.gif The drain valve has been leaking outside the pan.

 

[tanner]

Thanks to all of your advice, I found my problem. This afternoon I began disassembling the mower and inspecting all the pulleys, shafts, etc. Suddenly I discovered that the lock nut is missing on the right spindle shaft. Of course, the key is missing as well. Tomorrow I'll go purchase a new lock nut and key. Clean everything and re-assemble. With a little luck, I'll be back in the seat mowing tomorrow afternoon. Thanks again for all the advice!

 

[Bird]

Greg, my Bush Hog finish mower lost the lock nut and key once, and the pulley came off the spindle. I had a lock nut on hand, but never could find a woodruff key of the right size, so I finally ground one down to fit.

 

[Dozernut]

Way to go! Your now a veteran!/w3tcompact/icons/clever.gif

 

[Inspector507]

Bird,
Thats what the bench grinder is for...........improvising
/w3tcompact/icons/laugh.gif
Glad you're still with us /w3tcompact/icons/smile.gif

 

[tanner]

thanks dozernut! It is pretty [censored] exciting to be able to fix this problem on my own (with your and others help!) I'm a newbie to the country life, so it doesn't take much to excite me!