588, 526

S

Stew

Guest
Hi, just installed a 588 with a 526tid-20 transducer. In a 100 fathoms at idle or stopped dead in the water the recorder marks the bottom fine. As soon as I increase the speed, rpm the screen starts to lose the bottom, blank spots with intermittent marks of bottom.

This setup is installed on a 26’ pursuit inboard with a shaft drive. V hull with a couple of strakes. The transducer is at the rear of engine compartment on opposite side of raw water pickup. There is no disturbance in front of transducer.

Checked my wiring and connections. Power for unit comes from bus board, I get 12 to 14 volts. Transducer cable doesn’t run along side any alternator wiring.

I’ve read good reviews of this setup and a friend has this 526 transducer on a 26’ aluminum v hull and his recorder marks the bottom clear at 20 knots.

Would appreciate some input on troubleshooting my situation.

Going to hookup a 600 watt transducer on a pole and try run it.
 
Stew,
A sounder (by itself) doesn't know if the vessel is stationary or moving. The only difference is how water is moving over the face of the transducer. All hulls have a boundary layer and it's boundary layer that affects transducers, especially flush mounted ones. This boundary layer is a layer of water that has turbulence associated with it. This is why I like to recommend transducer that use fairing blocks. But here is what to look for. First start by using both frequencies at the dock. Next run your vessel in a straight line at 5 knot intervals (5,10,15 etc). The turbulence (boundary layer) will start to degrade the 50khz side first. It may appear as more clutter first and then progress (with more speed) as gaps in the bottom. As the speed increases the bottom on 50khz may completely disappear and the clutter/gaps will start to appear on the 200Khz side. One other test you can do is that if you have trim tabs (see below). This screen shot was from a DFF1 using a flush mounted transducer. Hope this information helps.

Snips
 

Attachments

  • RBM TT.jpg
    RBM TT.jpg
    587.8 KB · Views: 2,225
Snips, thanks for getting back to me. Well we put the boat in the water and tried
#1 disconnect the ground. No difference
#2 rerouted the transducer cable. No difference
#3 checked all the settings for transducer
#4 at speed under 8 knots trim tabs didn’t make a difference.
Dead in the water the recorder marks good to 200 fathoms.
Idle forward marks good but every so often loses the echo.
Slow forward up to 8 knots low frequency starts to lose signal.
Noticed the high frequency kept marking good down to 40 fathoms while the LF started to lose the bottom at 5 knots.
Didn’t try to run it pass trolling speed. But pretty sure the results will be the same or worst.
 

Attachments

  • IMG_2336.JPG
    IMG_2336.JPG
    41.7 KB · Views: 2,212
  • IMG_2342.JPG
    IMG_2342.JPG
    29.3 KB · Views: 2,212
Stew,
Unfortunately you are describing is very familiar. Below is a screen shot from a 55ft sportfisher with a FCV-1200 using 2kw transducers. Totally different hull, sounder and transducers. The only common thread was that the transducers were flush mounted.

Snips
 

Attachments

  • FCV-1200.jpg
    FCV-1200.jpg
    52 KB · Views: 2,215
Snips, so is there anything we can do to get this recorder to mark bottom at trolling speed?
And if it’s changing this transducer which one would you recommend?
We fish pelagics, ledges in the 100 to 300 fathom range is important around here.
 
Stew,
Do you have any pictures of your hull you can post?

Snips
 
These pics are of the starboard side of hull. If you look closely the 526 shows up.
 

Attachments

  • IMG_2351.JPG
    IMG_2351.JPG
    28.3 KB · Views: 2,202
  • IMG_2358.JPG
    IMG_2358.JPG
    29.4 KB · Views: 2,202
Stew,
Thanks for the pictures. Your rounded hull is very similar to this Grady White we added a sounder and sonar to awhile back. This gentlemen was a very avid fishermen and he wanted the best installation that he could get. He was also willing to rearrange a few items to make it happen. We used a B-260 transducer that was mounted on the vessels center line and incorporated the B-260 fairing into the fairing for the sonar. One draw back was that the resulting fairing was to low for getting the vessel of the trailer so he added 4" risers to the bunks to accommodate it. Yes it was a project but the end result was a clean picture at running speed. Below are a few pictures.

Snips
 

Attachments

  • 29 knots.jpg
    29 knots.jpg
    84.8 KB · Views: 2,194
  • 100_1272.JPG
    100_1272.JPG
    156.3 KB · Views: 2,194
  • 100_0877.JPG
    100_0877.JPG
    113.1 KB · Views: 2,194
Snips,
Thank you for your help and advice on my situation. I’ll be looking at the hull and trailer fit today. Mounting from the rear 1/3 of this boat is not an option. Straight shaft, prop tucked in a tunnel and rudder all water disruptions.
I think we will be ending in or near the engine compartment.
If I where to mount this 260 with fairing block in the same place as my 526 is mounted now how would that be?

I know right in the center is the best case but I have a shaft running right down the middle.
Maybe a foot off to one side of the shaft?
If the face of transducer and fairing block end up being even with bottom.
I hoping you’ve seen other placements that will still end up with a clean picture.

I’ll get the dimensions of the transducer and fairing block.
Get an idea of where it could be mounted.

Again I really appreciate your support and knowledge. Wish I had read all you threads before we purchased this flat mount transducer.
 
Hey Snips that pic you posted of recorder screen, 29.1 SOG, Is that 167 fathoms it’s marking?
 
Stew,
If I remember correctly we were paying more attention to the sonar than the sounder this day. We were in about 750ft of water so we had the sounders range at 800ft. The posted screen shot was after we switched the range to 400ft headed back to the marina.

To answer your other post. When I am placing a transducer I always start with the lowest point on the hull. Most vessel manufactures won't leave a space to mount a transducer and the area you do have access to most likely won't be the best location. If I have a choice of two locations say outboard of the center line or more forward and on the CL, I would probably choose the more forward location that closer to the CL. This location may not be the best when running but will performance better when you need it most, fishing.

Snips
 
Hey Snips, these are a couple of pics of the hull bottom we are working with. No good options on the rear third of hull. Forward of the cutlass is I think where we are looking to mount the transducer, just a bit off to one side.

Going to measure up the fairing block and length of transducer all thread mounting shaft.
Might be able to place it directly under shaft-coupling transmission tail shaft.

What do you think?
 

Attachments

  • 63639E80-AD8C-45F4-ABBF-AF571BFB26DC.jpeg
    63639E80-AD8C-45F4-ABBF-AF571BFB26DC.jpeg
    53.7 KB · Views: 1,119
  • 26D4D795-7116-40D1-A37B-098C965A69F3.jpeg
    26D4D795-7116-40D1-A37B-098C965A69F3.jpeg
    50.3 KB · Views: 1,119
  • 7F50EF2B-3A0B-4224-8C09-45AC30219AB8.jpeg
    7F50EF2B-3A0B-4224-8C09-45AC30219AB8.jpeg
    38.9 KB · Views: 1,119
Stew,
What is your max speed again? I am curious about what looks like a small access panel in your first picture, is that for the shaft?

Snips
 
Yes Snips that panel is the shaft cover, beginning of tunnel. And to the right of that panell is the flat mounted 526 we installed.
This boat can do 20 knots max. We cruise 18 and troll 8 knots. Just a four cylinder Yanmar, real torque for such a small engine.
 
Stew,
I see using the B-260 fairing would be difficult. What about trying to pocket mount one on the center line.

Snips
 

Attachments

  • 100_0918.JPG
    100_0918.JPG
    454.9 KB · Views: 1,098
Back
Top