I have done this kind of recovery before. Here is what you can expect. Very little visibility on the bottom. If you do not stop before you hit the bottom and hover over it, you will have zero vis. The motor is probably burried in the muck so you will have to fish for it with your hands. Even if not, it will be partially burried and as soon as you touch it you will silt out. So, plan on doing a braille dive. Everything will be by feel including separating the motor from the bottom and your ascent to the surface.
You will need to be able to keep track of your time and your position in the water column without the benefit of gauges or computers.
When you separate the motor from the bottom you will need to be negative so that the pop does not shoot you to the surface. Remember the pressure differentials in shallow water are much greater.
Blowing a bag is problematic in zero vis, but if you know what you are doing with a bag and are able to clear away all of the obstacles it is possible. You have to watch out that the motor does not hit you on the way up.
Lakes are full of monofiliment. You will need to know how to cut yourself out of it and also how to be sure that when you release the motor from the bottom monofiliment from the motor does not entangle you.
You will need to have a safety diver who knows what he is doing ready to come cut you out in zero vis if you become hopelessly entangled.
The best you can hope for in a lake recovery of a motor is to be able to descend, stay off the bottom, locate the motor, tie a line to it, and come back to the surface. Then with no divers in the water, muscle it to the surface. Of course it could have landed on rocky strata and be waiting for you to come get it.
But that is not my experience. Depending on how it landed in the silt, you may never see it on the bottom.
All of this ignores the fact that when something goes down, it never lands where you think it did and where you think it hit the water is never where it actually did.
Sound like fun? -- the last time I went looking for an anchor in the water -- and the guy who lost it knew "exactly where it was" I did a pattern, saw no unusual dimples in the silt, surfaced and said, "go buy a new anchor".
Jerry
