Draft

[sparkdr220]

Does anyone know what the draft is on a 20sli? With the transponder mounted near the bottom of the pontoon what is the minimum depth recomendation. I looked at the specs on line and couldn't find anything. The river is getting a bit low by us.

 

[RiverBill]

Sparkdr220,

I have the 22 SSI 3 tube with the Mercury 150 XL (ext shaft) looks like my draft is about 30 inchs at the bottom of the skag. The transponder is mounted on the left tube at the lowest point possible. I have the depth alarm set at 4 ft. to be safe. Not sure if this helps you.

Riverbill

 

[Jim_R]

I would suggest getting in the water with a tape measure next time you have a normal load and are in the shallows. You want to compare depth guage readings with the tape, and then if you have tilt/trim, adjust tilt for shallows, and then note the reading on the gauge for future reference. I boat on a chain of lakes, and don't stress too much until my depth gauge reads 2 feet, but then I have already learned most of the shallow areas the hard way. :unsure:

 

[Retired Team Member1]

18" to 24" is average for a small pontoon with a balanced load. Stand on the stern deck and place a yard stick in the water at the corner to double-check! TB

 

[sparkdr220]

Thanks TB that is helpful. Good idea Jim R. I am trying to get a baseline as to how shallow I can go (without getting wet as I too am on the chain and avoid going in whenever possible As you know with the mud bottom there is also an issue with churning up mud (not good for the impeller)so I am also trying to take that into account. I am on the lower river. Where are you located?

 

[StevL]

As you know with the mud bottom there is also an issue with churning up mud (not good for the impeller)so I am also trying to take that into account.

I would assume there could be stumps or fallen debris in the water as well. With this in mind you may want to cruise in deeper waters, tilt the engine and proceed at idle pace in two/three/four feet of water. If you boat in shallow waters often I would make sure to have a extra prop, cotter pin, prop nut, pliers and wrench on board. A good idea anyway!

I set my depth alarm to 9 feet. I do this so if I'm cruising at 15 to 20 mph I have time to react if the alarm sounds. At those speeds you can go from 4 feet to bottom in a couple seconds.

The absolute best thing is to have local knowledge.

Best of luck!

Steve

BTW: Draft doesn't tell you much of the story. The load you're carrying, how you're loaded (balanced), and the water conditions have to enter the formula.

 

[mtudb24]

If you look at my pics in the gallery, you can just see the water line on the back tubes. Its about 16". I have the twin 32" elips on a 2275 rcw. The mercury pro xs has a standard gear case water pick up and 2 in the nose cone. I can idle and still pump water out with 95 percent of the outboard lower units out of the water.

On my buddies brand x boat, he is about another foot or so as he doesn't have low water pick ups

It' trial and error but if say you'd be fine at 2

todd

 

[sparkdr220]

Good points SteveL. To keep it simple I will start with 2 people on board with an even load then compensate from there. I am thinking I will measure from the waterline on the pontoon (as per mtudb24) to the bottom. Then if I subtract the distance from the waterline to the transducer, I should have a fairly accurate idea of when I will ground out. The river itself is 6ft deep in the center. The problem is it's in the 2ft range at my lift and dropping.

 

[sparkdr220]

After taking the measurements we have 5" from the bottom of the motor to riverbed. Since this is under optimal conditions....I think we will be using our Benny as a patio until we get some rain. It still beats the heck out of workin