Replacing in-hull transducer

[rjames]

I have a 1999 2800 SCR and the factory digital depth gauge shows 2 dashes on the dial. The depth gauge people tell me I have a bad in hull transducer. I would like to replace it and also add a depth/GPS system, also in hull if possible.

How do I feed the transducer wires through to the dash? What panels do I need to open and what are the logistics to getting the wire through to the dash?

Thanks.

[mmwjr]

Typically failure. Trace the old transducer wire and you may be able to use it as a pull wire for the new one. Cut the old one in the bilge and tie it to the new one to pull. However you may find the passages are filled to prevent fumes from getting forward.

[rjames]

Thanks for the quick response.

I followed the transducer cable into a really big glob of silicone on the bulk head. What would be place on the other side that it goes to? Can I get to it by taking off the panel where the throttle is, or is there a better way to get better access to the in hull transducer cable on a 1999 2800 SCR?

[Phillbo]

Can't you just replace the transducer and use the same wire from the old one?

[rjames]

The depth finder people told me that if you are getting 2 dashes, it is the transducer that is bad, not the gauge it self. I plan to attach the new transducer and drop it into the water, to make sure the one I have is bad, before replacing it.

[rjames]

I misread your reply. I have not heard of anyone cutting off the cable and attaching the transducer to the old cable. I thought since it will be wet, they needed to be one sealed unit, transducer and cable. It could very well be something wrong with the cable. I don't know where the problem lies.

[Kevlar7r]

I haven't heard of anyone doing that either, but I suppose its possible. Make the connection in a dry spot. Not sure if those are coaxial or bundled cables though.



One problem though, say you cut the wires on the old one, then cut the wire on your new one to connect it, and discover the problem was really the cable between the bilge and dash. You just threw away a new transducer.

[rjames]

The transducer needs to be as low in the bottom as possible, so it is going to be in a spot that gets wet. I think it is a coaxial wire as it is an RCA fitting.

[Kevlar7r]

I was suggesting make your splice further up the cable, in a dry spot. Not right at the transducer, if you decide to do that.

[mmwjr]

I have heard of a new transducer being spliced to an old cable however you must ensure they both have the same wiring and that you do a good job else the signal integrity will result in poor performance.

And yes it should be done inside the boat in a dry area.

With that said I would go through the effort to run the new cable all the way to the unit.

[Kevlar7r]

Someone replaced the radar on my boat in the past. They left the old wire in place and ran a new one.



Not really relevant, but made me think of it.

[rjames]

Thanks for the insight, but I was hoping someone would know which panel I need to open, to get to the cable, closer to the bulkhead, so I can pull it through. If someone knew where the cable feeds through, to get to the dash, that would be appreciated.

[Lawnman]

I just did a new fish finder GPS in my 98 2800 the panel in the aft cabin ,which would be right under the shift throttle control, opens up to feed the wires from the engine compartment to the dash.

[rjames]

That was the type of response I was looking for. You probably saved me a lot of work.

Thanks.

[Chillaxintoo]

rjames, I think I need to replace the transducer on my 98 2800scr, do you remember what the model was on the transducer when you replaced it? Did it look anything like the picture?

[rjames]

Sorry for the delay.

The one I purchased is this one Airmar which you fill with antifreeze, so is liquid filled and I glued to the hull with 3m 5200. It works great so far, but if I was to do it again I would try to find a puck based one that you simply glue to the hull, with no liquid filling, like the original one. I also have a depth finder attached and I didn't know where to put the transducer, so put it way in the back in front of the drain plug, which is always wet, and placed a bag full of shot lead on top of it to hold it in place with plans to eventually find a place to glue it, and have never gotten around to gluing it down, because it works great as it is.

The link above is dead so I don't know which unit you are referring to. The depth finder I purchased is this one http://greatlakesskipper.com/standar...r-finder-gauge. I have a feeling they will eventually go out of stock so now have an extra one.

[Chillaxintoo]

Thanks for the info. The pic I tried to send was of an Airmar P79 unit. I am confused though, is that what you had on the boat originally or is that what you replaced it with. I have seen just the transducer head for sale but you would have to have the liquid holding angle adapter already in place for that to work. I also purchased one of the D41 units from Great Lakes Skipper to replace my bad unit. It sounds like the P79 trans. will work with it from what you are saying so I guess I would just have to install all new worst case scenario.

[rjames]

The Airmar P79 is what I replaced the original with. the original was your typical solid puck. I was hoping to find one of those, but didn't before ordering the P79. The P79 has worked great and the antifreeze has not leaked out in two years. I suggest reconfirming the unit you purchased will work with the transducer from the people you are purchasing it from.

[Chillaxintoo]

All the specs look to match up but finding someone who knows anything about the old Standard Horizon D41 could be difficult. I was hoping maybe our boat came with the P79 so all I would have to do is replace the transducer part on top, less mess than getting everything prepped to bond the new part to the hull. Wishful thinking on a 20yo boat but it was worth a shot.

[rjames]

I keep thinking that there must be a solid puck style replacement transducer out there to work with that digital depth finder. If you find one, please share it on the post.