Sounder not workin at speed?
 

Garmin 188C GPS/Sounder combo, When I get above 8 kt. it stops giving depth info..... Transducer is stern mounted. Any ideas what is going on?

Lower the transducer? Is the transducer in a location that can get backwash or air?

After I broke one off, I raised the second one about 1/2" and in that raised position it did you you are experiencing. This year lowered back down and now keeps signal even at 35 mph!

Haven't changed height, and it has always worked where it is. Only change I can think of is I did wipe a thin coat of ablative on it this year.......yet it works fine <8 kts.:huh:

how old is the trans? could be on its last leg. Is it a duel freq?

Original.... so is older. Dual? I don't know. Looking for the manual. (maybe looking for a new unit...next year)

never paint transducer with bottom paint

I've been meaning to lower mine as well, although I think it is set to as low as it can go with the currently dirlled holes. I usually lose mine at around 25mph, but sometimes it cuts out lower, and sometimes works past 35mph too. I'll have to give it a try if/when I have to pull the boat mid-season for any reason.

Here's another possibility: has the transducer pivoted on the mount such that it is no longer in a "horizontal" position? My Garmin transducer has a toothed ring which the transducer loosely locks into and some times if you take a wave hard the transducer will move a tooth or 2 in the mount so that it no longer points down. You do not want to over tighten as this is a way to prevent breaking the mount on hard hits.

that was my thought but would be obvious if your looking at it. Tell tale would be if your fish arches are only half arches.

+1 with the bottom paint, get some goof off or something to take that off. Also, make sure the bottom of the transducer is on plane with the bottom of the boat.

+2, if thats the only change and now its not working the same it explains it.

Get the ablative off then..
Use the water based transducer paint, give the face a light sanding (400 grit) and brush it on. I think its made by MDR.

Ever get the sounder working? What was the solution for future reference?

Nope. Just been fishing.... Hope to hop in the water and try removing the ablative with 600 wetsand or scotchpad next week. For now, I've just been slowing down to bump troll for macks. I'll report in here when I get a round tuit.