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troy
21-05-2006, 10:43 AM
As i have posted this before i would like opinions on what i have been told.
My transducer sprays water up the side of the outboard.
The mechanic told me yesterday to lift the transducer up .
He stated that half the face of the transducer should be under the level of the hull.
Mine is below this level.
I also noticed one of the screws he told me to undo was not tightened right up and and will not go in any further .
Could this cause any damage as far as water getting in where the hole was drilled.
Also if i undo all the screws not only will i not get enough height but also will it effect the sealant once the screws are lossened.
And is the mechanic correct.
Thanks
Troy

wessel
21-05-2006, 01:53 PM
Troy

If your boat is out on a trailer, you have time to play.

If you undo screws, I would recommend you take them out completely, clean the holes and the screws up and then reseal when you put them back in.

Look around at some previous posts. Some guys have made their own brackets that fit over the transducer to prevent the spray from hitting the engine.

Water at speed exerts a lot of force. I mounted the fishfinder transducer and the little wheel for measuring the speed as per the Garmin instructions. In my view it was too low and I lifted the transducer by about 10 mm. Looking from the stern at the boat, that placed the bottom end of the transducer about 30 mm above from where the transom ends. The little speeding wheel was sticking out by about 1 mm at the most.

Long story short...... first trip out the little wheel was ripped out of its mounting bracket by the force of the water. I still have the bracket itself stuck to the transom, but the rest is now lying somewhere in the ocean.

The fishfinder transducer is still there and works a charm. I still get depth readings at speeds of up to 25 knots but after that it just looses the plot. Do yourself a favour and visit the local boatramp and big marine workshops. See what others have done and have a chat.

Hope it helps.

Wess

troy
21-05-2006, 03:21 PM
Thanks Wessel.
The mechanic told me to use a straight edge and the face of the transducer should be as he stated half way below the hull.
It is a fairly large transducer Lowrance X107CDF .
There is one screw that is only about three quarters in and i do not know the reason for this other than they did not drill it in enough as i cannot screw in in any further.
At the most i think i will only be able to lift it 5m and a bit concerned about re drilling that screw and what
I would you reseal the holes with.
Thanks
Troy
Am in a bit of a spot here as it is a long trip to the dealership as it is under warranty

wessel
21-05-2006, 07:45 PM
Mate, it is is difficult to give advice without a picture of the current setup you have on your boat.

I will be reluctant to have a transducer sticking out by the distances your mechanic is talking about.

I use a marine grade silicone for sealing everything on the boat, including holes I have drilled below the water line. In my opinion, the cheap 2 dollar tubes you can get are just not worth it.

I usually drill the hole and then try to get some silicone under pressure into the hole. I make sure that I have a blob of silicone sitting on top of the hole through which I then turn the screw in. The threads will pick up the silicone and hopefully self seal as it goes in.

Best of luck. With the time difference I am sure that some of the Aus guys will be back at their computers in the morning and will be able to give more advice. Especially if one of them has the same unit to which you are referring.

Regards

Wess

Wess

troy
21-05-2006, 07:52 PM
Wessel
Thanks mate.
Troy

frankj
21-05-2006, 10:51 PM
Troy

I have the same transducer.
I had problems with mine but for different reasons.
Basically I believe what your mechanic is saying is the optimum mounting position.
Mine is too low in the picture.
I also couldn't raise it enough, so I bit the bullet and decided to re-drill. Unfortunately when I removed the screws I noticed this brown resin like liquid seeping out of one of the holes.
The end result, one transom replacement underway. Water (fresh) had been seeping in to the transom through the outboard splashwell drains. The end result, brown wood pulp mache. (Dry rot) Be warned.

Considering the vee of your hull, it is hard to know what is the correct level for the transducer.
Personally, I would move the Transducer up until it's horizontal centreline was level with the hull bottom when viewed on the trasnducers vertical centreline.
That's what I will be doing when the transom is completed.

If you need to redrill, your present holes can be filled with Gel coat putty.
I would carefully drill the hole out slightly oversize to get rid of any old sealer.
Mix up your putty and use a syringe to inject it into the hole. Pull the plunger out of the syringe and pack the putty in. Work quickly. Fill the hole from the bottom out if possible to prevent air bubbles. A bit of tube on the end of the syringe will help here. When it s all dry you can top it off if necessary and sand and polish to blend in.

If you don't need to re-drill, but need to reposition.
Remove the screws and clean off any sealant you can.
Carefully drill a little deeper, the hole that is bottoming out.
Buy some 3M's 4200 fast cure sealant/adhesive.
Remove the plunger from a syringe and squeeze some 4200 into the syringe, replace the plunger and inject into the holes.

Good as new.

Frank

frankj
21-05-2006, 10:53 PM
Oh no

frankj
21-05-2006, 11:05 PM
Work in progress

frankj
21-05-2006, 11:13 PM
Original transducer position

flotsom
21-05-2006, 11:45 PM
got to www.lowrance.com then go to marine and follow the links to transducer installation, i have installed a large amount of transducers and no better way to explain then for you to read 1st hand. i have always used sikaflex as it is very durable sealant and works excellant. in most cases on most boats you will need a transducer cover to protect the motor from water spray, these are available from most boating outlets for around $25 powder coated white, if you are unable to find them i do know that northside marine in brisbane have them in stock.