Hydraulic transaxle leak in lawn mower.

[turfranger]

What is the thing to use to stop a leak on a hydraulic transaxle on a lawn mower?

 

[Roadworthy]

The obvious answer is to replace the leaking seal. After disassembling my Craftsman garden tractor I learned that is not a viable option. There was no way to check fluid level just an opening to add fluid. I drilled a hole just below the seam joining the two halves and installed a hydraulic jack plug. I can now fill from the top until fluid runs out my check hole. I think I got the jack plugs from eBay. My Craftsman uses good old standard transmission gear oil so I just used the heaviest I could find - I think it was 85W-140 or something like that.

 

[RandyT]

What is the thing to use to stop a leak on a hydraulic transaxle on a lawn mower?

Assuming we are talking about the 455 in your avatar. the common leak locations are the O rings on right side for the forward and reverse direction control, And seal for the differential lock rod on left side will slide outward over time and cause a leak. And the third location is the gasket between the transaxle and the hydraulic pump/drive motor on the front of the transaxle. All three require removing the transaxle to get access to the leak locations.