SR Mariner depth gauge error

[legends117]

Ok - I know the answer is "replace the old analog system with new"....but I just purchased the boat and there are 100 things that need some kind of service, so  before I spend $500 - $1500 on a new GPS / Depth sounder, please let me ask the question.  I just purchased a CP-25, the depth gauge seemed to be working well on the first day of sailing (and during my brief sea trial); then started acting erratic.  The needle was bouncing between 10 and 35 feet, in water that was less than 10.  I tried to adjust the "gain" on the settings, but now the meter won't show over 10' of water.

So, here is my question - does anyone have first hand experience with these instruments and have a suggestion for adjustment?  I understand the manufacturer is still doing repairs, so does anyone know if the defect is in the display gauge, or could it be something wrong with the the through hull transducer?

Thanks for your insight - JD

[deisher6]

Hey JD:
I thought that I was the only skipper with analog gauges!  We have owned two 1986 C-27's and both have had SRMariner depth and knot/log instruments.  The original (new) C-27 actually had digital readouts, the current (used) C-27 had analog readouts.  Like you when we first launched the boat 2 years ago it seemed like the depth meter was working, then like yours, it became erratic.  I tried everything that you tried with no success.  The depth meter only worked kit seemed when the boat was at the dock.  I could generally tell if the water was getting deeper or shallower, but not much else.  The knot/log instrument actually worked when the paddlewheel was barnacle free. 

So after two years of using the keel as a depth finder I just replaced both the instruments with Raymarine units, around $8-900.  It is a relief to have accurate instruments.  Of course the through hull fittings were not the same size but you can drill out the old ones and use the same holes to mount the new through hull fittings.  The displays are not the same size, so the new displays are mounted in the same place on a piece of 1/2 inch Starbord covering the older larger holes. 

As an added benefit the leaking in the head from the old instrument mountings is stopped.  I did not appreciate the amount of water that was coming in until we replaced the old displays.

This was not an urgent repair in that it did not compromise the safety of the boat and was not necessary to sail.  So the replacement was put off till the CFO/Admiral gave the go ahead.

Good Luck

regards charlie

[legends117]

Thanks Charlie.  I use a hand held GPS for my positioning and map info, but I believe a depth sounder would make anchoring a little easier.  I called SR Mariner today, and left a message for them.  Hopefully they will call me back.  Even if the repair is $200, that is a better short term investment for me than doing a total system upgrade. 

I have a knot meter on the boat as well, but the speed sensor wheel was pulled out and capped before I bought the boat.  My GPS tells me speed, so that instrument will get chucked when I do my upgrade. - JD

[moonlight]

But there are numerous off-the-shelf contemporary options UNDER $200, so why waste time and effort on that one for up to $200?  Go Humminbird or Hawkeye or Faria, to name a few ...

[relamb]

i had an older unit similar to this on my CP23 and it worked fine.  I am in the process of installing this new Hawkeye on my CP27.
http://smile.amazon.com/Norcross-Hawkeye-D10D-Depth-Sounder/dp/B000JEOEE0/ref=sr_1_1?ie=UTF8&qid=1438830376&sr=8-1&keywords=hawkeye+depth+finder    Less than $100.

The instrment is mounted, powered, and the transducer works through the hull beside the keel under the VBerth.  The manufacturer suggests testing the location by putting the transducer in a baggie full of water in the spot where you will mount it.   Seems to work fine like that, so next week I will epoxy it in place.
Spending several hundred on a fancy one with network capabilities will have to come later. at which point this will be a backup unit.
Rick

[legends117]

But there are numerous off-the-shelf contemporary options UNDER $200, so why waste time and effort on that one for up to $200?  Go Humminbird or Hawkeye or Faria, to name a few ...

I was overwhelmed by the different models. Any specific recommendation?

[legends117]

i had an older unit similar to this on my CP23 and it worked fine.  I am in the process of installing this new Hawkeye on my CP27.
http://smile.amazon.com/Norcross-Hawkeye-D10D-Depth-Sounder/dp/B000JEOEE0/ref=sr_1_1?ie=UTF8&qid=1438830376&sr=8-1&keywords=hawkeye+depth+finder    Less than $100.

The instrment is mounted, powered, and the transducer works through the hull beside the keel under the VBerth.  The manufacturer suggests testing the location by putting the transducer in a baggie full of water in the spot where you will mount it.   Seems to work fine like that, so next week I will epoxy it in place.
Spending several hundred on a fancy one with network capabilities will have to come later. at which point this will be a backup unit.
Rick

Thanks Rick.  Where did you mount it and what did you do with the original gauge?  The SR Mariner will leave a 4" hole on the bulkhead.  - JD

[relamb]

My CP23 had a 2" round hole with the depth gauge mounted to the starboard side of the companionway door.
My CP27 had a non-functional speed/temp gauge mounted down below the companionway to the right of the engine control panel.  I just used that hole.
The sensor is under the vberth in front, to the starboard side of where the keel forefoot is.  I had to move my baggie of water around to find a good spot.
Too close to the keel it would not read.  There's no hull penetraion, the transducer shoots through the hull.

To close off a 4" hole, cut a piece of starboard or thin teak board bigger than the hole.  Maybe square like a modern instrument display, and round the corners.
The 2" hole goes in the middle of that.  Make one for the inside, one for the outside, and then use the new gauge display to sandwich them together.
Use some sealant to prevent a leak on the outside.
Msybe you could take the face of your old gauge, paint it, and use it as the external sandwich piece, depending on how it's made.  It could be the bezel to cover the hole possibly.  Of course plan B is to try to fill the hole with epoxy and gel coat and try to get it to match, then drill a new hole.  ...not for me!

If you want to temporarily mount it, leave the old unit in place and mount the new someplace else in an auto gauge pod.  I have one of these under my companionway steps to hold a fuel gauge so I don't have to crawl down in the aft compartment and try to read the meter in the top of the tank.
There are many styles of these gauge pods.
http://smile.amazon.com/HOT-SYSTEM-Single-Exhaust-Voltage/dp/B00SD2KMTQ/ref=sr_1_9?ie=UTF8&qid=1438865919&sr=8-9&keywords=gauge+pod

[moonlight]

Yes, the internet can overwhelm us with options.
Try local.  See if an Academy or Bass Pro or Cabelas; whatever is near to you, has something on the shelf.  Set your limit ($100~150~200) and sort them by range.  Sadly though, they may have nothing.
But if they do, take what they've got.  Forget the rest.
And use the teak, or starboard, to make the bezel and fill the hole...
If you don't have a local store, make three selections of the variety and narrow it down.  But there are some really good full on chartplotters, with transducers, available for under $700 too; but maybe that just muddies the water ...

[relamb]

Update - although the instructions say to NOT caulk the transducer to the hull (use epoxy), I've done it before and it worked fine.
This week I "permanently" affixed the transducer inside the hull next to the keel, using a big wad of silicone caulk to just stick it down.
It works fine, good readings from shallow to 80-90 feet deep.  I (gently) grounded the keel nose first on a firm sand bank and sent my son overboard with a tape measure to measure actual water depth vs the sounder readings.  It appears my mounting spot inside the CP 27 hull was about a foot below the waterline.
I prefer to read actual depth, vs depth under the keel, so it will be offset to display actual depth and an alarm at around 8 feet (CP 27 draws 3.5 feet).

[wes]

Ha. If I set my alarm for 8 feet, it would be honking continuously. Coastal NC is pretty shallow - my marina has 5' on a good day, and I rarely see more than 12'. The depth finder is the most important piece of equipment on board!

Wes

[deisher6]

Hey JD:
Here is an 'Amen' from the coastal Carolina cruising section to Wes's comment.

Glad to hear that you have it sorted out.

Smooth Sailing.

regards charlie