Honda lawnmower hydrostatic transmission oil change and axle seal replacement

A detailed video demonstrating the removal of a Honda Master Series/ pro commercial lawnmower hydrostatic transmission. In this video I also demonstrate how to replace the axle seals as many of these older and often heavily used mowers will develop leaks on the axle seals.

00:00 - Start
00:41 - Shut off fuel and drain carb
01:11 - Remove rear wheel assemblies
01:40 - Remove transmission cover
02:26 - Remove input shaft roll pin
03:31 - Disconnect drive engagement cable
04:03 - Remove rear height adjusters and transmission hangers
06:09 - Cleaning and preparing transmission
09:05 - Transmission seal removal
10:39 - Transmission axle seal installation
13:14 - Draining transmission fluid
14:05 - Refilling and flushing transmission
16:21 - Bench bleeding transmission
18:18 - Verifying drive cable adjustment
18:56 - Transmission operational bleed procedure
19:39 - Post-operational bleed fluid check and adjustment
20:33 - Final drive test

Contrary to Honda's recommendations of never changing the hydrostatic fluid in these extremely well built transmissions that I recommend it should be changed at least once every 5 years or 300 hours of use whichever comes first. In the video I wasn't sure precisely how much hydrostat fluid is inside the transmission but I finally found the spec in the service manual. Total fluid is 11.84 fl oz which aligns roughly with what I put back into the tranny (remember we can't get 100% of the fluid out as there will be remnants inside the tranny).

Symptoms of my particular mower that warranted a full service were tiny fluid leaks on the ground, slower than normal transmission speeds, and delayed engagement. The fluid in my lawnmower was NEVER replaced and I performed 3 drain and fills on the transmission to get the fluid clean enough for long-term service.

Use ONLY genuine Honda hydrostatic fluid for best performance and to avoid damage.

Note that this procedure is ONLY for Honda Master series or Pro series (namely "HRxxx - HX, HXA, HMA, HXH" hydrostatic transmission-equipped lawnmowers that have a SHAFT input drive. If you have a HRR/HRN/HRX series then this procedure does not apply to your model.