Small Engines (Lawn Mowers, etc.): Yard King mower drives slow, rubber plug, transaxle

Question
Hi, I have a Yard King 50” rider mower with a 20 horse kohler engine, oh and it is hydrostatic.   I have heard that pushing a hydrostatic mower without engaging the hydrostatic relief could pump air into it and could cause it to not drive as fast as it should.  Well after hearing this I believe that this is the problem with my mower, I have tried to adjust the pedal but I just can’t get it to go any faster (it will only go as fast as a steady/fast paced walk, I know it should be going faster).  My question is there anything I could do to correct this or is this something I should leave to a mower mechanic.  And if so what would you think a job like this would cost?
Thanks,
Ryan

Answer
 Hello Ryan:

 Look on the Top of the Transaxle beside the Cooling Fan. Is there a Rubber Plug for Adding Fluid? If Yes, then Send me the OEM and Model Numbers Off the Transaxle Tag. With these I can Locate a Breakdown of the Transaxle and Better Assist you. You can Add Fluid to the Transaxle through these Plugs. If you have Pushed the Mower and Didnt Release the Hydro Release, then Air is in the System and it May or May Not Clear itself. Most times it will Clear. If it Doesnt Clear a Repair Shop is the Only One to Attemp the Repairs. Never Push a Hydro Transaxle without Opening the Hydro Bypass Valve. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John