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txcharlie
06-07-2009, 10:33 PM
Just purchased a 33/61 PP. I have a vibration in the mower deck. It is very noticable at 1/4 and 1/2 throttle. At full throttle, it's not as bad, but there is alot of play in the belts while running. I thought the blade(s) were bent from the shipper not using long forks when loading the palet onto the trailer. After inspecting the blades, I can not see any damage. Is it possible the blades were slightly bent, like 2mm, and causing the vibration?:usflag:

Mowingman
06-07-2009, 10:39 PM
Betteer have the dealer take a look at it. Could be a slightly bent spindle shaft or an out of round pulley. A very slightly bent blade will usually not cause a bad vibrtation. If the bend is noticable, then the blade could be the cause.

puppypaws
06-07-2009, 11:57 PM
Just purchased a 33/61 PP. I have a vibration in the mower deck. It is very noticable at 1/4 and 1/2 throttle. At full throttle, it's not as bad, but there is alot of play in the belts while running. I thought the blade(s) were bent from the shipper not using long forks when loading the palet onto the trailer. After inspecting the blades, I can not see any damage. Is it possible the blades were slightly bent, like 2mm, and causing the vibration?:usflag:

You have definitely got a problem, coming from no fault of yours. The dealer needs to take your mower and get it straightened out. It may be no more than a blade problem or something as severe as a warped deck. It could also be a bad belt or pulley, it is not your responsibility to be concerned. This is Bobcats responsibility, let us know what is done?

kaferhaus
06-08-2009, 08:43 AM
It's either out of balanced blades or a bent blade OR the spindle spacer between the blads and spindle is "cocked"... I've seen that one... the blade will look tight but the spacer can "****" on the spindle, gaul and wedge a bit sidways... but that usually causes a vibration at all speeds. I'm betting it's the blades.

Lawn Pawn
06-08-2009, 10:29 AM
My new zero turn had TERRIBLE VIBRATION at less than full throttle when I would throttle back to mow slower in super dusty or bad ground conditions.

Short version of story. Secured a rubber spacer under one tension spring to dampen vibrations.... and stretched a bicycle inner-tube over another tension spring. BIGGG improvement!!!

No harm done doing this.... runs much smoother and quieter.

puppypaws
06-08-2009, 12:28 PM
My new zero turn had TERRIBLE VIBRATION at less than full throttle when I would throttle back to mow slower in super dusty or bad ground conditions.

Short version of story. Secured a rubber spacer under one tension spring to dampen vibrations.... and stretched a bicycle inner-tube over another tension spring. BIGGG improvement!!!

No harm done doing this.... runs much smoother and quieter.

I'm sorry, but if there is a bad vibration; something out of the ordinary is causing this to take place. The only thing you should hear is the wind turbulence under the deck when the blades are engaged, and feel no vibration. If you have a blade causing vibration from hitting something while mowing or being out of balance really bad, it will wear the spindle bearing out faster than normal, sometimes much faster.

Lawn Pawn
06-08-2009, 01:52 PM
I'm sorry, but if there is a bad vibration; something out of the ordinary is causing this to take place. The only thing you should hear is the wind turbulence under the deck when the blades are engaged, and feel no vibration. If you have a blade causing vibration from hitting something while mowing or being out of balance really bad, it will wear the spindle bearing out faster than normal, sometimes much faster.

You are 100% correct..... I did the above, and even replaced a spindle that was running warmer than the others. But in-fact it was a spring vibrating and pounding on the deck... for what ever reason. Personally I think it should be of a different tension... more clearance or a change in geometry in the bell-crank?

The inner tube was just to fine-tune as it were a ...sympathetic.. I think that's the word to use.. vibration in a much longer and lighter duty spring that would vibrate in a circular motion depending on engine RPM.

txcharlie
06-08-2009, 08:06 PM
Thanks for all the input. Will update when a solution is found.

txcharlie
07-24-2009, 07:57 PM
Well, took it to local dealer and he replaced the deck belt. It is some better, but not a lot. I just don't run the deck at low speed and it works OK.

Mowingman
07-24-2009, 08:25 PM
Check the groove in each belt pulley on the deck. You could have a small piece of wood chip, or a small rock down in one of those grooves. It will make the belt jump and cause a vibration.

Blood Bought
07-24-2009, 08:52 PM
Did the dealer pull the blades and check the balance? Did he check the idler pulleys with the belt off for rough bearings? Did he check each blade spindle while the belt was off for warp or sticky bearings? Any pulley that is grabbing will create vibration as well as out of balance blades. If vibration is still there the problem is not fixed.

topsites
07-24-2009, 08:55 PM
You really want to know the truth, and we shouldn't have to do this but if you want a machine to run good
I have learned that when I buy a new one, as soon as I get it home and long before it sees any work, I go
over the whole thing piece by piece.
You'd be surprised how many inconsistencies slip past either at the assembly line or when they put it together at the dealer's.
Sad...

Really sad, the dealers are supposed to be the experts here, but I usually find at least a half dozen things that need
adjusting or tweaking or outright fixing. It ain't right, but it has saved me many a 'warranty' trip back to the dealership,
which, about the only thing that's guaranteed is that if you don't go over it, break down it will.

Did the dealer pull the blades and check the balance? Did he check the idler pulleys with the belt off for rough bearings? Did he check each blade spindle while the belt was off for warp or sticky bearings? Any pulley that is grabbing will create vibration as well as out of balance blades. If vibration is still there the problem is not fixed.

Omg are you kidding, and I'm not saying they shouldn't have done as much,
but I doubt they did more than the perfunctory checks, if they even did all those.

The perfunctory checks:
1. DO it run?
> Yes / No.

2. Uhhhh....

3....

4. Go back to 1 and WHEN it runs call the customer!
> Tell'm it's fixed and ready.

Blood Bought
07-24-2009, 09:00 PM
Omg are you kidding, and I'm not saying they shouldn't have done as much,
but I doubt they did more than the perfunctory checks, if they even did all those.

The perfunctory checks:
1. DO it run?
> Yes / No.

2. Uhhhh....

3....

4. Go back to 1 and WHEN it runs call the customer!
> Tell'm it's fixed and ready.

AMAN! AMAN! It's bad but unless you have an EXECPTIONAL dealer you have to direct and watch to get the service you BOUGHT!

jk mow & more
07-25-2009, 08:52 AM
Just purchased a 33/61 PP. I have a vibration in the mower deck. It is very noticable at 1/4 and 1/2 throttle. At full throttle, it's not as bad, but there is alot of play in the belts while running. I thought the blade(s) were bent from the shipper not using long forks when loading the palet onto the trailer. After inspecting the blades, I can not see any damage. Is it possible the blades were slightly bent, like 2mm, and causing the vibration?:usflag:

had same problem all three spindles the bearings were spun and need complete new spindles

Pennington Lawncare
07-25-2009, 09:26 AM
The belts on mine don't stay in a straight line when turning either. If you don't have the PTO engaged there is still a slight amount of belt flexing just with the engine running. That can only be attributed to a slight vibration in the engine. I did have the PTO belt start to shred with me 2 days ago @ 100 hours. I felt the vibration caused by that instantly and knew something was up. I raised the floor pan and looked at the belts and saw the cord out of the PTO belt had started to come out. Just one nylon string essentially was dangling at one spot.

One thing I have discovered is to never use Gates Industrial belts on a lawn mower Hi-Power II I think is their model of industrial belts. I know the belt was a 5/8 x 101" and these Gates belts have a very rounded back side and they don't run worth a crap on a back side idler pulley. I had already tried one on my old Cub Cadet and within 30 minutes it had completely shredded and I tried one on my Bob-Cat yesterday and I engaged the blades and cut less than a minute and then looked at the belt and it had begun to twist as it went through the idler pulleys. Luckily the belt was not damaged yet and I returned it and bought another belt made by Dayco that is also an industrial belt but, it's back side is relatively flat and was used through 4 yards yesterday with no visible wear so hopefully it'll last long enough for me to get an OEM belt from the nearest dealer 40 miles away.