Z425 Noise

[depawl52]

So my z425 is very loud when the mower is engaged. It's about 7 or 8 years old, and has always been rather loud but seems to have gotten worse as it's gotten older. I've removed the deck belt and checked all the pulleys/bearings and they all appear to be rotating freely (at least as far as I can tell spinning them manually). I've got new blades to try (next spring), but I was wondering if the blades need to be aligned? Or does the blade alignment not matter? I thought I vaguely remember reading somewhere that the center blade needs to be at a 90 degree angle with the 2 outside blades (that may have been a different mower).
Thanks for any input.

 

[mechanic mark]

First noise is probably coming from deck idler pulleys, you have to remove them to properly inspect them for wear & bearing noise, always use JD OEM Parts. Blade timing is important, put center blade vertical & outside blades horizontal.

John Deere Model Z425 Zero Turn Mower Parts, Page 4

 

[bertsmobile1]

If the blades are driven with a V belt then the answer is no because they will slip over time
If he blades are driven by a toothed belt ( like a timing belt in your car ) then the blade position is important
When you take the old blades off, check their balance.
Pounds to peanuts they will all be out of balance.
Check the tension arm pivot for looseness & wear .
Without the belts on the blades should spin dead quiet, if not replace the bearings which you should have been greasing regularly .

 

[depawl52]

Thank you for the responses. This deck has 3 drive pulleys and 3 idler pulleys. The drive pulleys have grease fittings and have been greased annually. I don't see any way to lubricate the idler pulleys. Two of the idler pulleys and one of the drive pulleys are pretty noisy when spun manually, so I'm going to replace all the idler pulleys and the drive pulley spindles, as well as the blades. Hopefully this will solve, or at least improve the issue.

 

[bertsmobile1]

Idlers are throw aways and on average get changed every 2nd to 3rd belt ( if they wear out & don't break )