Transducer mounting location

[WoundedOne]

I have installed 2 new transom mount transducers one for 798 CI HD SI and one for Helix 5 DI. The one on left is SI. I know that SI should be ran at idle or just a little above. I took the boat out yesterday to do some adjustments. I found that i get a little feed back on SI anything above idle. My question is should i move it farther away from center line of boat than it already is? i am also going to drop it down and see if that give me any better result. I also think the polyurethane plate may be a little high. (When mounting this plate i took advantage of a hole already drilled).

As for the DI i get really erratic readings from depth to just a DI image. The depth will show 300 + feet in 13 feet of water. Is this just a setting or ?

As for the DI when i am up on plane it is out of water.I know i need to lower the Ducer and that might help with the above problem with DI/

Any help with location and overall setup would be greatly appreciated. I have attached a few pics of Ducer mounting feel free to give me some advise

 

[rps]

I am not a pro, but I've had more than one unit on every one of the boats I've owned since 1982.

1. make sure the ducer is not behind something, like a strake, which causes water turbulence. In the picture it appears the ducers, mostly the SI one, sit behind the cavity caused by the step up from the hull V.

2. Sit the ducers so they sit about 1/8th of an inch below the hull line. At speed you will have slightly better readouts and you can read at faster than idle if not on plane. 1/8th of an inch minimizes the risk of breaking the ducer off on debris.

Others with more knowledge may contradict me. I will defer to them. I am only stating what I have learned doing it myself.

[WoundedOne]

@RPS would you think if i dropped the the SI ducer down another 1\2 inch with just adj or would i need to move the poly block lower to bottom of hull?  with all of this i did seal up some major leaks i was having.

having both ducers on outside of strake was planned. I still have some room to play with  and lots of sealant....

 

Thanks Randy