New (to me) 721d - first cut

[tdeutsch]

Brought home my new/old mower a couple weeks ago. It's a 1994ish 721d with a 61" deck and 13xx hours. I cleaned the deck, (did the last guy ever clean the deck? I don't think so) installed floating bushings, greased everything, changed the alternator belt, etc. I didn't time myself cutting my yard (about 1.5 acres) but I know it was plenty fast. Amazing engine. Gobs of torque!
My only concern is what seems like a difference between the left and right hydro action. When I push hard forward on the right side, the sound changes from the normal hydro whine to a hiss or slip (hard to describe - what with the blades and engine going). I don't plan on "flooring" the thing at all - I don't need to mow that fast - just wanted to see what would happen I guess. Should I just not do that and not worry about it? Am I in for it? Do I just need to change the belt or tensioner or adjust something?
Also, what are the little bent metal levers sticking out of each hydro unit? Some kind of relief valve or something? Does it matter how they are positioned?
I hope nothing awful is wrong with this beast. It's total overkill for my lawn, but I love it anyway.
Glad to join the forum!

 

[bobbysr]

My advise is to call Grasshopper and give them your serial#. They will email (free) you an owners manual, or send a paper one for a fee. The bent levers ar your dump valves. NEVER push the mower unless you engage the valves. It puts the mower in a free wheeling mode. I'm not too sure about the noise that your hearing. Engage and dis-engage your PTO at the lowest possible RPM's. This will pro-long the life of your clutch.

 

[tdeutsch]

Thanks, Bobby. How can I tell when the dump valves are engaged? Do I pull out on them to disengage? And do they lock in place somehow engaged or disengaged? Right now they are just sitting there all bent and wiggling around. This is difficult to describe, so I guess I'll just go out and poke around on it. But I appreciate the answer. I'll give Grasshopper tech a call about the manual.

 

[bobbysr]

I can't remember exactly what the G1 trans dump valves look like. But most of them are basicaly like a bolt. Right-to-tight and the mower works normal. One full turn to loose, and the mower should freewheel.