Hull Construction for new depth finder?

CNYBoater

Active Member
Aug 14, 2017
386
Boat Info
1994 200 Overnighter, Single Axle Easy Load'r Galvanized Trailer, 2006 Toyota Tacoma Double Cab
Engines
Single 1994 Mercury Black Max V135 O/B
I recently purchased a 1994 200 Overnighter. The depth gauge in the dash powers up on the Lowrance 3500 but I sometimes get the no reading -- at speed and the readings don't seem to match up to the Navtronics sonar charts. Since this has a 23 year old transponder thru the hull I would like to replace everything and just leave the old transponder where it is. I like the in dash Faria depth gauge online but the shoot thru hull transponder is not compatible with cored hulls. Can anyone tell me if my 1994 Sea Ray 200 Overnighter has a cored or solid fiberglass hull in the rear bilge area?
 
Almost certainly your boat is solid fiberglass. SR used and still uses coring on it bigger boats. My 37 foot SR was solid glass for the hull. Your's too.
 
As mentioned, solid hull. But try cleaning off the outside of the transducer, first. Also, if it's a very soft or weedy bottom, that can mess up the signal.
 
I spoke with someone in another thread looking for the dash unit. They said the lowrance 3500 has a shoot through hull transponder which is why I can't see it from the outside. I'll put on a HEPA mask and try buffing away the bottom paint in that area. I trailer the boat so it shouldn't be a big deal. If I don't see an improvement I'll try a new unit. I'm getting the no reading on lake bed and river bed so maybe it's the bottom conditions. Either way if I don't see an improvement a newer unit can't hurt.

Thank you for the replies.
 
In "most" cases, a "thru" hull transducer is/was used (especially if factory done or most Sea Ray dealers). However, most people don't even realize that it is there. It only sticks through maybe 1/4" at most. It's just a round, disc - about 3" or 4" in diameter and flat to the hull. Once the hull has been bottom painted it almost disappears... and after years and years of (improper) bottom painting... well, you get the idea. Post a picture of the transducer from inside the boat.
 
Last edited:
Finally figured out how to resize an image to get this inserted. I haven't previously needed to worry about file size because I don't generally post photos online.

Below is the transducer, just forward and to the port side of the bilge pump which is directly in front of the drain (green grass showing). So the transducer is the size you described. If I can find a way to safely remove the bilge paint without the EPA showing up in my yard then I'll clean off that area to see if it makes a difference. If not, I think it may be best to leave the old transducer installed and see if I have a place to clean up and glass in a new shoot thru hull that Faria sells. This was a factory installed option like the hydraulic steering, so do they really last 23 years?
fullsizeoutput_541.jpeg
 
I took a picture this weekend before heading to the launch. This is the underside of the hull in the area the transducer would be. There is a semi-paste at the store called Aqua-Strip that supposedly removes up to five layers of bottom paint, no VOC, non-flammable, etc. I think I'll try a small container and focus on this area. You scrap it off after it changes color with a plastic putty knife. I can then bag the waste up and leave at the waste station at the county transfer station (aka dump). Several applications may be needed based on the product reviews.

IMG_0244.JPG


Unfortunately I have no results this weekend on how the depth gauge worked in a different area of the lake. Got to the launch and starter was spinning at good speed not advancing to the flywheel. Wasted two hours round trip and a no go for our second outing with the new boat. Battery is on the charger (I drained it with so many attempts to start and lowering/raising the outboard several times). Removed the starter, cleaned off the gear and shaft, applied new oil and seems to have more free spin up and down. Also pulled the armature out, cleaned a lot of green off the conductive rods the coils are attached to. Cleaned off the copper commutor as well. Brushes and brush springs looked fine. wiped off a ton of material from the sleeve magnets. Found no cracks in them, but the armature went back in with a good bit of magnetic pull when all said and down. I'll just have to hope next weekend is nice enough to do the lake trail. Starter needs to go back on, and I'm going to try her on the muffs again the night prior to launch.
 

Forum statistics

Threads
112,872
Messages
1,420,835
Members
60,871
Latest member
cbrcassio
Back
Top