hydro-gear rebuild

ILENGINE

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You didn't accidently turn the charge pump cover 180 degrees when you reinstalled it. If that pump cover is turned around it will cause the pump to run backwards, and the main pump and drive won't get any oil.
 

gregjo1948

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I don't believe I installed the cover 180 out, but I will check it to make sure. I don't really understand how it would run backwards. I didn't mark the cover before removing it and I reinstalled it the same as the cover on the other transaxle. Would the covers form right and left side be 180 degrees different?
 
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ILENGINE

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I don't believe I installed the cover 180 out, but I will check it to make sure. I don't really understand how it would run backwards. I didn't mark the cover before removing it and I reinstalled it the same as the cover on the other transaxle. Would the covers form right and left side be 180 degrees different?
Yes that came be and in most cases are the opposite direction. the gerotor oil pump housing is offset from center which when rotated 180 degrees out cause the oil to flow in the opposite direction.

Looks like from your model number the charge pump cover should have the dot next to the bolt if the cover is round or the square end of the cover that is oblong should face the case cover.

This maybe will help https://www.hydro-gear.com/service-repair-manuals/ Scroll down to the ZT-2800 ,ZT-3100, ZT3200, ZT-3400 service manual and then download it for your unit. The cover orientation page is 31 in the manual.
 

gregjo1948

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I didn't look for any marks to identify which way to install the cover. I just switched it 180 and that fixed the problem. Thank you for the help, gregjo1948
 

ILENGINE

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Don't feel bad, Getting the charge pump cover turned 180 is probably the most common error that occurs when people take the unit apart. Hydrogear always tells their dealers to mark the charge pump cover and the case to avoid getting it rotated. Still the biggest issue they come across.
 

sgkent

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one of these will help solve that issue. I always mark things the first time they come apart.
 

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gregjo1948

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one of these will help solve that issue. I always mark things the first time they come apart.
Have one just like that. I usually just grab a screwdriver and leave my mark.
 
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