Sounder Problem Need Help

[Guiddo]

Have a 1991 Grady White 23' Gulfstream powere by 2000 Yamaha 250 - 2 stroke- wanted to upgrade the sounder - talked to South Shore and went with their advice on the Furuno 620 unit - they did the installation with a transom mount transducer - the problem is that I lose contact with the bottom (and everything between ) as soon as I ramp up the rpm's to get on plane - when I come off the throttle and move along at 2 mph the bottom returns as well as al the relevant marks

Assumed turbulance was the issue - South Shore has made every effort to correct the situation to no avail - last week I went so far as to have them install a thru hull transducer, but sadly the same results. So I have a significant investment here for a unit that does not work.

I am at a loss as to where to go from here - SS has talked to Furuno, with no suggestions from them as to what could be the problem

Would appreciate input from anyone on options - I cannot believe there is no set-up that will work with my boat - the unit that was on it when I purchased the boat was also a Furuno - it did not lose bottom, but was not able to detect fish at cruising speed - that is why I upgraded - the boat was purchased primarily for fishing.

I do not feel safe not knowing how much water is under me when undeway - even ran aground in Sandusky Bay last year when a sand bar had shifted over the winter - no damage or injury, but it is an issue.

Thanks for any advise or input

[-C-IMP]

Found a thread that said to set transom mount deep enough to be below air bubbles created by hull. Another said to use "High Speed Fairing Block' when using thru hull setup. Sounds like turbulence is the problem.

[Rough House]

Some of the guys i know run 2 transducers. one on the transom and one inside the hull. Whether it be a shoot thru the hull or in hull transducer thats up to you. Alot of the bass guys that run boats like rangers use 2 transducers. You should check out The hull truth forum. Lots of guys have this same problem on boats like yours and you can see what they did to fix it.
Good Luck
RH

[Guiddo]

Will do - where does the hull truth forum reside

Thanks for the suggestion

[Rough House]

www.thehulltruth.com/ Loads of information on that site.

[wajski]

I had the same problem with my 2320sl parker I installed a thru hull with high speed fairing block. I can't believe the resualts what a difference, mine is 3'+- from my O/b. I have a 225 Yahama on a Armstrong bracket