Jump to content
vic008

Navman 5500 crook

Recommended Posts

36 minutes ago, wheels said:

Fish, your unit has possibly got fouling on it's surface. The weaker signal bounces off the Keel and it gets a false shallow reading.
Too much AF paint can also do it.

Thanks Wheels, we did check that, no AF on the transducer itself. It did have barnacles on it, we were happy we thought we had fixed it - it made no difference at all...

Is it a thing that the transducer coils can get old and short / fail? The gear is fairly old. It was the first new lectronic item we installed on the boat, and we've had it for 20 yrs, so it is in the order of 18-20 yrs old now.

Share this post


Link to post
Share on other sites

I cant say never when it comes to lectronics and that fellow Murphy. But it is not a common way for them to go. Normally it is go or no go. However, if you had no AF coating on it,  then growth could once again be an issue. It only takes a week or so for any clear realestate to be snapped up by those marine invaders. You do need to put some kind of coating on the transducer. Just ensure old is removed before new applied so it does not get too thick.

Share this post


Link to post
Share on other sites
1 hour ago, Jon said:

IMHO 

You have got twice the design life out of this unit.

The easiest fix will be replacement 

Agree Jon, its just a pain in the arse drying the boat out for long enough to swap the transducers (Coppercoat, so we don't haul out ever, just clean between tides and change anodes, service prop), and the general time and boat money involved. We already have a Garmin plotter on an NMEA2k system so just need the transducer.

It did give me thought to just not use a sounder. The only time I really need one is anchoring, to know how much chain put out. All the times I've hit things or run aground, the sounder was no use anyway. Sounds don't warn of rocks that leap out infront of you... I understand the mark 1 lead line never needs firmware upgrades either...

Share this post


Link to post
Share on other sites

Not having a sounder is like not wearing your seatbelt. It can also be a navigation aid when coastal cruising. Use can use it to follow depth contours and that helps plot your position on the chart. I hate entering an unknown bay without one.

Share this post


Link to post
Share on other sites
15 hours ago, wheels said:

Not having a sounder is like not wearing your seatbelt. It can also be a navigation aid when coastal cruising. Use can use it to follow depth contours and that helps plot your position on the chart. I hate entering an unknown bay without one.

I don't think so. I would describe it more as driving around with one tail light not working. The driving with no seat belt analogy would probably better fit having no working VHF onboard, IMO. In terms of nav, I've got a chart plotter in the cockpit. I have done blind nav exercises in the past where depth is integral to establishing your position, but it is never required outside of Yachtmaster examinations. I have sufficient compasses to triangulate, and have back up GPS and charts if I have a systems failure. 

I take your point on entering unkown bays, that is a valuable use of a sounder. But right now I'm not planning on entering unknown bays. I just want to go sailing and enter my regular, well known bays. I do want to replace it, but it is a question of probably $1,000 and 2 or 3 days work (including hauling out), or I could just go sailing and be a bit more cautious. And take a lead line for checking how much chain I need out. in terms of crossing the bar, I can predict the depth as accurately as the sounder can tell me, so that is not an issue.

In saying all of that, my sounder is still working, it just flashes intermittently. I can still use it for depth and nav, at the moment. It will stop working all together soon. I just need to carry a lead line as back up I think.

Share this post


Link to post
Share on other sites

I cant agree with that fish. Your compasses are not much use  for position fixing in poor visibility - like fog, or night (unless to get a bearing on a light). The depth finder is a great source of data to help you check position. Its often an easy way to double check your GPS/plotter position... but locally, in good conditions, your probably fine.

The flashing numbers mean the unit has lost the bottom, or its too soft to get a consistent reading. Check all the wiring for pinholes in the insulation (corrosion) , and all connections for tightness and cleanliness. This issue could well be cables or connectors.

Most of the new (Throughhull) transducers are 51mm, so if that is the size of the through hull, then a new unit can likely use the same housing. New housings though have the flap that closes when you remove the transducer, so let in lots less water while changing. If you send me a pic of the transducer plug, I may have one in my 2nd hand junk you can try....

New fish finder/depth sounders start at about $600, with a transom mounted skimmer transducer.

 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...