Garmin Depth display readout question

[tgaston]

I'm a dealer in Southeast Florida and we do a lot of electronics installs. Typically we see the Garmin flash when it has "lost" bottom. We have found that it will find bottom immediately if you put the "range" into manual mode by picking a depth range that you know your in.

When the sonar looses bottom it pings from its deepest range until it finds bottom again, which can at times take awhile and be frustrating. I have always had it find bottom immediately in manual range.

I don't have a lot of experience loosing bottom in muddy conditions, because of our location, but I would think the gain setting would remedy this.

 

[BaseCampAnne]

Thanks for the input so far. Doing the manual step may be similar to what Bob Ostlund is talking about...

I hope this might be the key to being able to transition to shallow water and get accurate readings!

Thanks!

 

[walldog]

When I moved my transducer from the stern to midship at the head bilge, I eliminated my readout problems.

 

[Pete]

During our shake down cruise last fall in the Puget Sound depth measurement was fine but since moving my boat to Florida this summer I've had a variation on the problems mentioned in this thread. At slow speeds the readings are consistent and accurate but on a plane the readout starts blinking and in say, 7 ft of water, readings jump around from the teens to several hundred feet. In other words, any reading except the correct one. Cruising the ICW and bays of SW Florida with no reliable means of depth measurement is not to be recommended.

I had a similar problem on a previous boat with a thru hull transducer and that was resolved (as Walldog has suggested) by moving the transducer to another location. But if location is the issue I imagine just about every Ranger owner in Florida and other shallow water cruising areas would have commented in these forums and/or reported the issue to Ranger. That doesn't seem to be the case.

Andrew asked me to update my software (done) and make sure the sonar gain is on Auto (it is) but still no useful reading on plane. Unless there are other suggestions I will follow Paradox's advice and go to maximum gain. Any other advice especially from the shallow water cruisers out there?

Pete

 

[knotflying]

The access to the transducer can be difficult on the R-27, but have you checked to make sure your fluid in the hull connection is adequate. Improper fluid level and with the stern at an angle when at high speed may be the perfect scenario for your problem. The fluid is anti freeze. I have seen this issue before on another boat (an R-25) and once we filled the fluid up, it was resolved.

 

[baz]

So where exactly is this transducer contraption on my MY2010 R-25 ? Curious to know so I can check fluid issue that Mike has mentioned. Thanks. 🙂

 

[knotflying]

The one I worked on was an older r-25, if I remember correctly it should be at the stern below the center storage. It is attached directly to the hull. It is a two piece installation; a piece that adheres to the hull and then the transducer which can be turned and then sets level. The fluid pours into the piece that adheres to the hull. The particular installation that had the problem was that they used silicone to adhere it to the hull and it gave way so the fluid leaked out. You should use 4200 or Life Seal, let it dry and then pour in the fluid and set the transducer. I also made sure the transducer was working by putting it in the water and it immediately read the depth. Also, before you go through all this trouble did you disconnect power to the unit for a master reset? I have had to do this twice when I had similar issues and that worked. You need to physically remove the power cord to the unit. Just because you turn off the unit this does not disconnect the power supply to it.

 

[Levitation]

Given my experiences (along with Mike's help) I strongly suggest checking the fluid level in the sonar well as your first step.
It is back near the steering ram. Open the swinging doors under the stern seat (and empty the junk 🙂 then open the white trap door on the floor. Down (waaay down) and to the left of the keel you will see it. Turn counter clockwise to pull the transducer out of the well. Use any kind of antifreeze (though RV antifreeze is better for the environment) and fill it about halfway full. Put the head back into the well (yes it will overflow) and lock by turning clockwise.

Let me make editorial comments that access is vastly better under there (for any reason) if you remove the ice chest (you shouldn't be drinking that much beer in the first place🙂
Also, I have sawed off the center piece of the swinging doors opening and added aluminum tabs with wing nuts to put it back on. Having the entire opening free of the center obstruction makes diving for the stern thruster possible.

 

[Pete]

Thanks guys I'll check antifreeze level.

I was assuming the difference between the unit working perfectly last fall and now failing, is water depth - perhaps turbulence when on plane in shallow water is preventing the sensing unit from getting a good read. But as I said in my post, if that was the case then other shallow water cruisers would have the same problem. A leak would also explain good performance last fall and bad performance now. I assume the location of the transducer on the 27 is the same as on the 25.

Pete

 

[knotflying]

I have an R-27 and when I was having issues with mine I tried to get to it. UGH!! I never did get to it and luckily it was the "removing the power cord" trick that got me back in action. So good luck getting to it and let us know how it worked out.

 

[walldog]

I have an R-27 and when I was having issues with mine I tried to get to it. UGH!! I never did get to it and luckily it was the "removing the power cord" trick that got me back in action. So good luck getting to it and let us know how it worked out.

Some R27s have the transducer epoxied to the hull without the mounting bracket. Impossible to remove when it fails. This makes it necessary to mount a new one in another location. As Knotflying suggested use 4200 to attach the mounting bracket to the hull. Properly the deadrise needs to be measured and the mounting bracket installed as indicted so that the transducer can shoot straight down and not off at an angle. The instructions with a new transducer are excellent giving good advice as to the best location to mount the transducer to minimize errors from turbulance, etc.

 

[Pete]

Update.

Andrew confirmed the transducer is epoxied straight to the hull - no fluids involved.

Garmin thinks it's likely a cavitation problem. This would explain why it only occurs on plane and (I wish I could remember my fluid mechanics) in very shallow water. They suggested playing around with Gain and Range (strength of signal). If that doesn't work it probably means finding a different transducer location.

Pete

 

[knotflying]

I would think if it was a location issue we would all be having the same problem. Hopefully it is a setting issue.

 

[baz]

...snip...

Let me make editorial comments that access is vastly better under there (for any reason) if you remove the ice chest (you shouldn't be drinking that much beer in the first place🙂
Also, I have sawed off the center piece of the swinging doors opening and added aluminum tabs with wing nuts to put it back on. Having the entire opening free of the center obstruction makes diving for the stern thruster possible.

Removing the center piece of the swinging doors opening is an EXCELLENT suggestion/advice. Adding the tabs for reinstallation is also EXCELLENT idea. The only person that can get into my stern seat storage area is my 2 year old granddaughter and her Mom frowns on that... :lol: Child labor was outlawed some years ago I believe, but my granddaughter is unaware of those laws. :roll:

 

[baz]

As an update to my OP I must say that of late I'm not having any real issues with my Garmin depth readouts. It will occasionally flash when depth is several hundreds of feet (for example over 500 feet). However, this is the only readout flashing I see these days. The shallow water depth readings are quite solid without flashing issues.

It could also be related to my cruise speeds I maintain these days which are a lot less than when we first started to use the boat. This aspect tends to lean toward what Pete has mentioned about cavitation when on plane affecting the transducer's ability to accurately determine sea bed location.

Now that I know where to look I will be sticking my head down under the stern center locker to gawk at this contraption, and hopefully will be able to extract myself. 😉

 

[baz]

Before doing damage to myself I decided to see if I could find the depth transducer by looking toward the stern from the engine bay. I think I found it attached to the hull directly beneath the waste tank on the starboard side. I managed to get a photo of it. It was black and cylindrical with numbers (1, 2,3, 4, etc) on its edge. A black tube/line came out of this a was routed forward. It had a label attached to it and managed to get a poor quality photo of it as well.

Is this the Garmin depth transducer ?

Ha ha (just joking)

Is this the transducer ?

This was the label attached to the black line/tube leading from the black top

 

[walldog]

That is it.

 

[baz]

Thanks Herb. 🙂 This is much easier to view and access the transducer via the rear of engine bay rather than down through the stern locker.

 

[RProffer]

Before doing much troubleshooting on the transducer, I would recommend doing a software update or reload. That seems to fix a lot of quirks with Garmin.

 

[Tugalong]

We had problems with our Garmin in the beginning, it was located where Garmin recommended towards the rear, however, on checking with the factory they recommended moving it to more the centre of the boat. This was done and hey presto we had accurate readings. I think it was related to turbulance.