Hustler Super Z with FH721V - leaking oil- engine replacement?

StarTech

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
It should be RH threads and considering it is a Kawasaki it should a metric size. But off the top my head I just don't know the actual size. I haven't taken one off in a few years but this why I have a complete set of Metric wrenches from 8mm to 30mm available to use if needed.

And seems I always needing to buy more wrenches and sockets every month. Now I got get a 22mm impact socket just to change the wheels on my truck. Nearly 10K in tools and I still having to buy more.:rolleyes:
 

driveguy

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
Well. just a heads up for anyone who reads this. The fitting nut for the oil cooler is 1". And the nut is so narrow I had to machine off the taper/chamfer on a $9 socket to get enough engagement with the nut. otherwise I just round the very outside edge off of it. I've been too busy with work and taxes to work on it much BUT the grass is growing, and I expect to have it done in 2 weeks. Will update then.



IMG_9347.jpg
 

driveguy

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
Well. weeks later it's almost there. work, taxes, family. and more work. So. does anyone have any good pictures of the front and back control panel connections as it relates to the governor arm, spring, shaft, and throttle linkage. I feel like something isn't right. I set it per the manual which states:

Turn the top end of the governor arm counterclockwise to fully open the carburetor [G] throttle valve and hold it there.
Turn the governor shaft counterclockwise fully to the end of its travel.
Tighten the clamp nut.

Which I did, and the arm lines up with the shaft exactly where it did before disassembly, because I do have a picture of that. The linkage is installed correctly as well. I believe the governor spring is, but maybe the arm on the control panel that rotates isn't in the correct orientation or sequence or???

So the problem. When I try to rotate the throttle arm on the control panel it tries to open the throttle more and starts to flex the linkage from the governor arm to the throttle. Maybe I'm confused on how this works. When I manual move the governor arm down (clockwise) the throttle will move down (clockwise), which I assume is closed (clockwise is closed, rotates the throttle toward some kind of stop screw), (counterclockwise is open...per the manual even.... and it rotates the throttle toward a hard stop). At this point I'm scratching my head.

Any pics? thoughts? guidance?
 

driveguy

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
have a friend whose dad has the exact mower and same engine +/- a year or 2. Looked at his. I had the governor and linkage correct, but when I tightened the clamp it would shift the arm just a hair. So had to be a little more aware of keeping the governor arm from moving. and the answer to my question is, yes I was confused on how governors work on these small engines. So learning something every day.
 

StarTech

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
Well. just a heads up for anyone who reads this. The fitting nut for the oil cooler is 1". And the nut is so narrow I had to machine off the taper/chamfer on a $9 socket to get enough engagement with the nut. otherwise I just round the very outside edge off of it. I've been too busy with work and taxes to work on it much BUT the grass is growing, and I expect to have it done in 2 weeks. Will update then.



View attachment 60098
That is something I do to a lot of my smaller sockets for the same reason. Shallow fasteners heads.
 

driveguy

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
Alright. last update for a while. It's together and running. Sounds great. no leaks so far. I will be watching it closely the first few weeks. So here's all that I did:
Replaced:
Top and bottom shaft seals
Governor shaft seal
Crankcase gasket
PCV Valve and cover gasket (left the stop and breather foam thing)
Oil Cooler o-ring
Valve cover gaskets
Adjusted valve clearance
and of course intake and exhaust manifold gaskets
Dipstick tube o-ring
Spark plugs, oil filter, fuel filter
Cleaned the hydro cooling coils

I have about 10 hours on it already and so far so good. I'm really glad I broke the engine down this far and replaced everything I could. I feel like I would be right back at it in another year or 2 otherwise. I learned so much about small engines doing this. I never did get a price from a dealer on a full seal replacement, but the couple I called wanted $450-$600 for just the bottom shaft seal. So I'm guessing it would have been $1200 or more to break this engine down. idk. At least that's what I'm telling my wife, so I can go spend $1000 on something I want! lol. I think I have $175 into it including the drive pulley I bought.
 

driveguy

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  • / Hustler Super Z with FH721V - leaking oil- engine replacement?
Ok. I'm back for a quick update. Have about 60-70 hours on it since the seals were replaced. Zero leaks. Zero issue. Runs like a champ. Makes me feel great to take on a new and different challenge.
 
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