Did you run your tranny wire from the head unit to the transducer, completely seperate to any engine wiring or power / battery wires? From the looks of it where your screen has heaps of green all through it (first few pics), it appears to be getting interference from somewhere. If it's near engine / charging wiring, that would explain the slower speed having less interference (slower engine rpm therefore less charge output). 

the only problem ther times I have seen something similar is if you have a phone or GoPro plugged into a cigarette lighter plug charger on the dash or near the screen. Whilst plugged in for charging, it made the screen experience heaps of interference. 
 

hope that helps 

Thanks for the reply scano. I can certainly look into that, from memory it is on the same side but not next to the main power cable. I did try revving the motor which showed no interference at all, but that's obviously in neutral and not loaded up.

what boat do you have?

I have the Elite 7ti also, on my 660 Trailcraft, which have the same problem & starting to get really over it..

Heading to a Sounder night @ Tacklewest on the 29th which hope to pick up some tips / look at alternative options within a certain price range.

will be following this thread though

Interesting read on the setup of your transducer.

Specifically points out that if the transducer is out of the water it will not read bottom.

It also says :-

. Hold the whole assembly up against the transom or transom
step to the desired position. If mounting on the transom, align
the bottom of the transducer with the bottom of boat. Use a
pencil to mark the pilot holes (D). The transom mounting plate
has screw slots for adjusting the transducer position height

Holding your ruler underneath the hull it should line up with the bottom of your transducer (sit on top), from your photo's it looks to high to me ??

Your side and down scan will only work at slow speeds, chirp should read no problems at speed. Are you running chirp only at speed ?

I have pretty much read the manual only and seen your photo's so just a guess really. Hope that helps.

Cheers

I should have said sitting too low compared to the ruler

 the first photo looks like it could be facing forward too much depending how you boat sits when up and about on the plane

Google elite ti fishwrecked and read the threads.  Mine is hopeless with totalscan unless I am doing 5 knots or less and it is calm, same problem all depths, when drifting I get a good picture.  I have tried so many different spots for the transducer the mounting board on the transom looks like swiss cheese. I siliconed a hds DFSHBL 50/200 khz inside my boat, firing through the hull, it reads great at all speeds (over 30 knots), but you need a solid glass hull to shoot through.

 I have an elite 9 ti that I use for maps, the totalscan is still hooked up and I read bottom at 20 knots. My old man also has one that is his primary sounder and his also reads bottom at cruising speed without clutter.

 I can't attach photos to this thread but if you like give me your phone number and I'll send some pics.

 i'd be very interested to see the set up too. i have the elite 9 with same problem with noise on the screen at speed. 

I re-ran the cable (temporarily) across the floor and tried it on the weekend. Didn't seem to make much difference. I raised the tranny height at the same time and managed to get a few extra knots out of it but the screen still became cluttered as before. I will keep playing with tranny position and setting and keep the thread updated for other Elite Ti/Totalscan users. Cheers, Trav

With basically the same settings/position as above I tried trimming the motor up and it cleared the screen right up and I was able to get a good reading at 15Kns+.

Only problem is I had to trim the motor up to the point that it was very easy to cavitate. Might still have to play with tranny position a bit, maybe out further from the motor?

settings now on low for both noise rejection and surface clarity.

Trav 

 Hi Trav,

I have an Elite 9 with a Totalscan transducer and was ready to Bin it. I tried all sorts of positions on a reefrunner and ended up inverting the unit so the wire comes out the back and it improved, Just undo the 6 bolts holding it on the bracket and flip it and put it back together. Then change the screen and flip that as well for side scan. I thought the cable might have been producing bubbles. That made a difference. The Transducer for chirp is at the cable end with it now at the rear, it is in deeper water and hopefully cleaner water.  then I went one step further and stuck it under the hull on the keel and im good for 30 knots and not to mention sidescan is now clear of the motor blocking the beam. I have some cavitation issues in a tight turn but its all good 98 percent of the time. Move yours further away from the prop as your last update tells me its tubulence from the motor as well.  You may also be getting air bubbles off the welds right at the rear of the hull. it doesnt take much to mess up the water flow. Look for a nice flat area ahead of the unit. It is a black art with Transducer placement and the advice from others is all good. Keep trying!

Your not going to get anything in that washing machine ,on the last photo.
I would suggest you bolt it to a skeg (like a surfboard ) put that on a pole that you can flip up & down and put it well down in the water column .
Chines are too close together and boat is to short to get a good amount of water displacement to obtain clean water at the back of the boat.
Ali boats do not displace enough water(heavy enough)Aspeaserly the Quinney.
Slow speed Only!
IMO.