Long time subcriber & reader - Only my second time seeking assistance. My apologies up front for the lengthy post - I've tried to be thorough, tho....
First off:
2013 GRAVELY ZT60 HD (w/ Kawasaki FR730V)
Model: 991084
S/N: 021187
Warranty Code: HB
Hydro Gear Commercial ZT-3100 Drive System
Has 903.7 hours on a working hour meter.
I've owned it a year now. I mow a 4 acre yard about every 4-7 days from March through mid November.
I've done a full engine tune up twice now (oil, oil filter, air filter, fuel filter, plugs; and blades with blades I got with the mower & sharpened).
I have several concerns:
#1 it seems to lose power while mowing thicker grass, but not too high - level ground & unlevel ground at medium speeds. If I slow down, the revs climb back up to normal. I do not ever mow at full/high speed - although I believe this mower should be able to handle it. Doesn't burn/use any noticeable amount of oil between oil changes. I have basic tools, but nothing to check compression or tear into the engine ....
Where can I find printable/download able manuals for mower & engine?
#2 It seems to have a pretty significant vibration - at least more than I feel should be normal. The vibration is there when its running w/out PTO engaged. I believe there may be a failing spindle or pulley, possibly even both because the vibration is more notable when the PTO is engaged. The blades are not bent/warped/out of balance.
What's a good/reputable source of OEM blades, spindles, pulleys, belts - & part numbers for each?
#3 - least concerning is the last time I mowed the main belt from the PTO clutch to the deck 'jumped' off when I disengaged the PTO after a couple hours mowing. I didn't find anything broken and was able to put it back on and tested it w/out it happening again.
PTO engaged & disengaged several times after mowing for a few minutes at a time.
This is my second ZT. My first was a 50" deck Toro Time Cutter SS5000 that I bought new from a big box store.
Okay ... good question. I always run the mower at full throttle when mowing. Only throttle down when I place it in park to get off and pick up debris or grab another bottle of water. So, not mowing at high speed means just that - I am not going fast over ground.
We can now proceed.
If you don’t have a tachometer, get one. There are some decent digital tachometers to be had on Amazon. Get one that has an alligator clip on the end of the wire.
Set your high idle at 3,600 rpms, with no load (PTO Off). Set low speed idle to specifications.
Set your governor to specifications.
Vibrations: Check your deck belt for wear. Replace if there are any cracks or chunks of rubber missing.
Check your spindles and idler pulleys. Do they spin without noise? Is there any side to side or up and down slop? Replace if either is the case. You will need to remove the deck belt to do the inspection.
Parts: I like Rotary brand aftermarket parts.
Blades: OEM or equivalent. Rotary part #6083 is a good choice.
