How to test liberty z hydro??

Brawnyrebel

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Good afternoon all, I just picked up a used liberty z 48" and am having an issue with the left side drive. If I give full left forward there is a skipping feeling like something slipping. I have purged the system of air and replaced the drive belt. Is there a procedure somewhere for testing the pressure of the pump to narrow down which side of the transaxle needs fixed? I'm fairly confident that I can fix the problem myself if I can narrow it down.

Any help is greatly appreciated.
 

bertsmobile1

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If the engine pulley is behind the drive pulleys then the left side always packs it in way before the right
2 reasons for this
1) the deck tosses more debris on the left side so it runs hotter with resulting thinner oil
2) the slcak side of the belt is the left pulley so the belt tends to slip a lot on the left pulley
This means that the left side turns slower with thinner oil so you get a lot more wear on the internals on the left side
To counter this most good quality newer ZTR's run the drive belt in a V shape rather than the original triangle so the left pulley has more contact between the belt & the pulley.
A lot are also going to plain belts or raw edge belts to get more friction ( thus drive ) between the pulleys & the belts .
I expect eventually we will see drives with bigger pulleys on the "pull" side and a slightly smaller pulley on the "push " side
So if this was a cheap used mower there is a good reason for the price reduction.
New pump-motor units are an easy drop in repair, just time consuming .
 

Brawnyrebel

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If the engine pulley is behind the drive pulleys then the left side always packs it in way before the right
2 reasons for this
1) the deck tosses more debris on the left side so it runs hotter with resulting thinner oil
2) the slcak side of the belt is the left pulley so the belt tends to slip a lot on the left pulley
This means that the left side turns slower with thinner oil so you get a lot more wear on the internals on the left side
To counter this most good quality newer ZTR's run the drive belt in a V shape rather than the original triangle so the left pulley has more contact between the belt & the pulley.
A lot are also going to plain belts or raw edge belts to get more friction ( thus drive ) between the pulleys & the belts .
I expect eventually we will see drives with bigger pulleys on the "pull" side and a slightly smaller pulley on the "push " side
So if this was a cheap used mower there is a good reason for the price reduction.
New pump-motor units are an easy drop in repair, just time consuming .
I appreciate the reply and that makes perfect sense. I was hoping to open the transaxle and replace a few seals and valves or something, putting a $1300 transaxle in this mower just doesn't make financial sense.
 

bertsmobile1

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Depending upon the exact model the drop in replacements are not particularly expensive in the USA
Down here a common K46 drop is in $ 800 ( Aus ) plus another $ 400 for me pulling the hydro repairing & replacing it .
Luckily I have a repair shop handy who refaces the worn parts then shims them to the correct clearance , refits & purges the box so all have to do is remove & replace .
Apparently in the USA the parts price is so cheap that reconditioning is not financially viable .
Lots of You tube videos showing it being done ( badly mostly ) but at least yo u can see where the damage occurs & how it is fixed .
The vital thing is CLEAN & I mean really clean
They are assembled in dust free factories for good reasons
 
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