Also, be sure you go far enough toward the bluff (cabin) on the Big Su BEFORE you make the turn to the Deshka, otherwise you may be buying a new prop, or lower unit, or set of teeth, or all of the above. Several times that I had gone to the Deshka I would see someone cut that turn and hit the gravel bar.
Yes it's possible
I ran a prop on the Su & Yetna for years. 40 yamaha prop.
Prior to the Deshka landing all we had was Susitna landing. Doable from there too.
From the new Deshka landing, pretty easy, follow the channel, water plenty deep.
Go with someone who knows how to read the water.
Got a jet last year. Lots easier but less power & more fuel.
Doable with a prop, but mistakes are costly.
Learning curve is pretty steep at the cost of new props.
Take extra props , hammer & a file
You say run the Deshka so I am assuming you mean running the Deshka and not running to the Deshka. I get wide eyed running the Deshka in a jet boat a lot of times. Between the shallows and the other boats that can cause you to get in the shallows, Unless the water is high your asking for trouble with a prop up more then a mile from the mouth. The Su is no problem at all if you know how to read water. Seen plenty of boats, prop and jet, polishing there bottoms on that stretch.
Years ago, before outboard jets begin showing up in AK, people used a "jackass" lift to lift their prop up to get over the shallow spots. Many changed out the Aluminum props for Brass props and carried a hammer and something for an anvil to straighten out the bent prop blades after hitting something hard enough to cause a serious vibration. Before The Susitna Landing came into being, way before the Deshka Landing, we ran up and down Willow Creek, jumping log jams, and dodging air boats to get in and out of the Big Su.. So, yes it's do-able, but I wouldn't recommend going upriver on the Deshka more than a mile. There was a rocky stretch up river a ways that everyone called "The Can Opener" .
At mile 11, its called the "rock garden". The water is slow and there are tons of boulders that don't show a wake on the surface. They all have aluminum color on them from years of boat traffic.
Last week I watched a couple guys cruising along in a small jetboat run smack into a rock that was about 4" under water at the bottom of the rock garden. It tossed them and the dog around pretty good. They kept on going after checking everything out. An hour later they came cruising back down and narrowly missed another rock just under the surface by inches. Ignorance is bliss sometimes as they had no clue what they were doing.
A jackass lift with a prop won't allow you to run 3" of water for 100' at a time. Heck, most jetboats can barely do that. Thats why everybody up there runs airboats, there is a reason.
If you were talking about the Deshka landing, then sure you can run a prop out of there, but up the deshka river, this time of year, you won't make it very far at all.
I run down to the mouth all the time in my prop and have zero issues. Like others have said though I don't get much further up river than a mile. If the water is high I can get pretty far but that is a rare occurrence.