I just changed out my 2011 928 wheeled 2 stage Honda. The left hydro trans seal popped out, the one that is the stubby one with the bearing on it on the left side as you are holding the bars like you are blowing snow. The right one was pushed out a bit and I cleaning out the right hand side gear box grease and replaced it with some Shaeffer's moly synthetic grease I for got to replace the right side hydro seal. I cleaned the seal area and took a long wooden q-tip shaft with some 3M marine adhesive sealer, IE outboard/transom bolt sealer and pushed in the seal, cleaned the area with 91% alcohol and put the sealer in the small area around the outer seal making sure to not get any on the shaft or inside shaft hole seal area. So basically sealing in the seal as making it have to push past the sealer if it wanted to pop out some more. The left side I added black permatex to the out side of the seal to help hold it in when installing it. I now wished I thought of this before and used this extra sealer on the outside of the left seal as I did with the "Hail Mary save"of the right seal that started to push out. I let the unit sit for 24 hours before running it. I will keep the seal and extra one if needed for a later repair if this doesn't work.
I did this by flipping up the machine on the bucket and small jack stands on their side to have the machine leaning forward a bit. I drained what was left in the hydro trans first thing before starting this repair. The color of the oil was like new brown car oil, and a good lot of black crud came out that was settled on the bottom from summer storage. If I could of ram the trans all that black crud would have been mixed in the oil...hence the load of black crud in the reservoir we hear people saying their older unit have, as I did. I used one of my gun barrel cleaning q-tips to clean the bottom of the trans floor through the drain hole and added a shot glass of oil and drained again. Black crud came out, but a lot less.
I am not a fan of any oil Honda uses, and at work I deal with a boutique high end industrial oil company and do testing on all of our equipment that has high stress or is smart to keep track of with oil analysis as common sense standard practice. So I do know oils and mostly go with group 4 and group 5 oils as default. I did extensive research on finding out what Honda uses for its hydro oil and as always it is nothing special and nothing unique. Just Honda with it's usual "casting of FUD" (fear, uncertainty and doubt) to get you to use their crappy oil. We see this in their cheap crappy DW-1 ATF trans fluid. Nothing but cheap ATF and nothing special or unique. Even cheap and good Valvoline Max-Life synthetic ATF is superior to cheap Honda's DW-1. But I digress.
I found out many lawn care companies that use Honda commercial lawn tractors don't use Honda hydro trans fluid that is speced for them, the exact same that is speced for the 2 stage snowblower's hydro trans. A group of owners use Castrol oil synthetic 5w-30 car motor oil. One guy gave yearly updates on how the machines were running with this oil and all were running 3 to 5 years after seasonal commercial use. He got better change times and less crap in the oil using synthetic car oil. I used 75% 5W-30 Amsoil Signature Series and 25% 0W-40 Redline oil. A group 4 and group 5 oil.
I refilled the trans by filling it to the fullest I could get the drain hole filled while flipped up. I hand tightened the drain plug in. At this point the machine trans was not fully level, the drain plug was a hair LOWER then the reservoir point that when the machine is down in it's normal running position the reservoir tube attachment point it the highest point of the trans point for fluid. While still in the exact position with the drain plug just a hair lower then the reservoir tube attachment point I slowly filled the unattached from holding bracket reservoir and let the oil drain down the tube into the trans and filled the reservoir half full of oil. I then took a pin punch and rotated wheel axle about ten times both ways (fun). I then spun the snow chute facing forward and set the end diverter to fully up and pulled the jacks from the bucket and let the machine roll forward to be held up by the chute. This lets the drain be higher then the reservoir tube attachment point. I then unscrewed the drain plug and burped just a bit of air out and then just oil came out. (rags tightly around drain area). Drain tightened, added more 5W-30 oil in the reservoir to get it to about the 1/3 level after attaching it back the the handlebars, added gas and it ran EXACTLY like a new Honda hydro without even a whisker hint it had hydro oil change to 5W-30 (which is the closest viscosity to Honda Hydro fluid). Ran it for 10 minutes around the driveway and yard, and now I am ready for Minnesota winters. I had planned to change out the original Honda trans fluid this year since the reservoir had a lot of black crud in it, but to my surprise I had a puddle of oil under the left axle from the seal push out.
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