Hey all. I just bought a 1986 242 and have several questions but will start with just this one. I need to install a Garmin 540s GPS. I would lie to put a in-hull transducer but need some advice as to whether it will work and where to put it. Where have you put yours? Thru hull is my least favorite position as I really don't want to cut a hole in the hull. I had a transom mount on a small Scout. Thanks

I will have to dig to find pics of my mount. Mine is shooting through the hull but there was no drilling or holes involved. When the layup of a hull is solid the signal can shoot through with no problem. To give a solid connection for the install I used the "slow" dry epoxy recommended by the mfgr of the transducer. I prepped the area for the mounting making sure there were no voids and clean, then build a dam out of plumbers putty so the puck and epoxy could sit still and level out against the angle of the deadrise. Once it was dry I pulled the plumbers putty off and the puck was sealed to the inside of the bilge shooting straight down.
I don't remember the brand at the moment but I chose it because it will shoot at the same time other transducers are shooting from the boat without getting mixed signals or interfering with other machines.

Aqua...thanks, that's what I needed to know, that the hull is solid in the engine bay. I saw a brass? transformer that was more expensive but they say it works better. I assumed you put it in the engine area?

Yes in the engine bilge on the floor. The original sounder was glued in the same place. The original one was just glued flat to the angle of the bilge but it used a wide cone angle so the transducer mounted at 24° was not a problem. If you go back with a system that uses a wide angle sounding cone then the angle of the bilge floor is not a problem to just stick the transducer on it. If the transducer needs a level orientation for the cone angle to work then making a dam to seal it in level still works fine.

Be sure to use a "slow" dry epoxy so that air bubbles have time to rise out. If there are any voids between the hull and the transducer the signal will deteriorate or not work.
I used a 1 or 2 hour drying material.

My boat mechanic, who specializes in go-fast and engine building (Kurt's Marine)says he would usually grind into the hull to create a flatter area. That the fiberglass is really thick in the bilge and then do the epoxy thing. I'm going to have him do it while he also adds a sea strainer , tune up the engine, and I am redoing the dash to have a built in GPS. Necessary items for the Bay areas where I will be boating.

Just so I understand...you are pulling cooling water thru a strainer and sea cock as opposed to thru the drive?...Just curious.

And yes...I agree with Aqua...put it in the bilge. I have not done my Formula yet but when I did my Sea Ray 40 EC I 5200 sealed it to the bilge floor and it was flawless. I'm not a fan of drilling any more holes than necessary.

Actually, I don't have an answer for you yet as to where the cooling water is pulled from. When the Bravo drive brings the water in, does it go through an external line into the engine? If yes, I would put the strainer in line with that. I have heard of guys putting thru hull water pick ups to raise the level that the water is pulled from. Good for shallow bay areas. There can be a lot of muck in the rivers where we boat. Manasquan River and Barnegat Bay. I will find out once he has the boat.