Datamarine Instruments

Feb 18, 2022
440
Catalina 36 Port Orchard
Luna has a couple Datamarine instruments in the cockpit area near the companionway hatch. I have no documentation on these or the transducers. Does anyone know where I can find information on these? Is Datamarine still in business? And how hard is it to remove the transducers while still in the water?

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May 17, 2004
5,390
Beneteau Oceanis 37 Havre de Grace
Datamarine itself is no longer in business, but I think you can still get some parts and service from DMI Marine, Inc., at least you could a few years ago.

Removing the transducer in the water should be possible assuming you have a dummy plug, though I’d want to do it on land first to make sure the dummy plug fits properly and there are no unexpected hang ups. A very exciting amount of water comes through a hole that size, and I don’t think Datamarine used any kind of flapper to reduce the flow as more modern makers do.
 
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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
Datamarine made very good, very nice looking and long lasting instruments. They date back to the 1970's. I worked in a marine electronics place in the summer of 1980 when I was in engineering school, and they were around then, and I repaired quite a few of them.

The guy who owns the assets now, DMI, Inc, is a bit sketchy, and I've heard stories of poor service from him. He's basically selling off what remains of the part inventory, and doing some repairs. Reviews have not been super.

The transducers: the speed sensor may be removable, that is, there may be a plug-like cartridge that contains the impeller and sensor, but as mentioned above, make sure you have the right plug if you pull it. The depth transducer is typically not removable, but it's usually not necessary to remove it, it will likely be compatible with any new depth instrument you buy. I think they are usually 200kHz transducers. This is unless you go to a system that integrates electronics into the transducer and interfaces to NMEA 2K or something.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
21,972
CAL 35 Cruiser #21 moored EVERETT WA
And how hard is it to remove the transducers while still in the water?
NOT HARD AT ALL... Remember that joke about the Doctor that preformed a surgery to perfection. Recevied accolades from his fellows for the brilliance in his cuts and the unique way he reconnected all the vital organs... Only fly in the ointment... the patient died.

Removing a transducer of that vintage, is either through the hull of the boat, and there will be leaking as you work to get the thing out of the 1" to 1.25" hole... or it is not through the hull, but just sitting inside against the hole - in which case go for it. No problem or leakage exposure.
 
Feb 18, 2022
440
Catalina 36 Port Orchard
Well the patient dying is not what I want to accomplish here. And I think I found a plug for the hole. (No pic yet)

This is most likely the speed transducer as I believe it would be difficult to determine depth from that angle. There is another one of these through hulls in the engine bay that goes straight down, which I figure to be depth.

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I am going to guess there a pretty healthy collection of sea life growing on the sensor so it will not work without some serious cleaning.

I like what these instruments look like, but it seems I will most likely be replacing them with something else in the future if they are not going to be serviceable.

I did run across the DMI website, but it didn’t look like a site for marine instruments. It had a dog and a guy on a Harley. It seemed more like a hand made fan site type web page than one of a business.
 
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Feb 18, 2022
440
Catalina 36 Port Orchard
Since Datamarine is no longer a thing, who then makes gauges similar to these? They are using a 4” hole in the cabin.
 

jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
Since Datamarine is no longer a thing, who then makes gauges similar to these? They are using a 4” hole in the cabin.
Yea, that's a problem, since newer instruments use smaller holes. On my C36 I made some nice bezels of Starboard to plug the big holes and mount the new gauges.

Do you know if they work? If you don't need or want an integrated instrument system, if just depth and speed are O.K. for you, you might just continue to use them.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
21,972
CAL 35 Cruiser #21 moored EVERETT WA
I took a face like that, left the trim sides and cut out the center instrument, that just happened to be the diameter of the autopilot control for my Raymarine AP.

I have seen others use starboard or fiberglass to cover the hole and resurface the area. Some attach a starboard or wood cover for the hole then drill a smaller hole to insert an instrument that is of a smaller diameter.

You could also go the other direction and enlarge the hole, inserting a port to bring more light into the cabin.
 
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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
I know a guy who had a boat with DM instruments, and wanted to replace them with newer. Whoever had installed the DM instruments originally left the hole-saw cut-outs on the boat, and the owner saved them. The new owner very carefully, craft-ily glassed them back in and gel-coated the scars on the outside so well that one could barely detect that they had ever been cut out. Surely, one must be quite an artist and craftsman to accomplish this, but it's possible.

I hate, on my own boat, how someone - maybe the builder? - hole-sawed great holes into the main bulkhead to mount car-style speakers. Ugh! Oh, well, they sound good, but I would have much preferred some discreetly positioned speaker boxes.
 
Feb 26, 2004
22,888
Catalina 34 224 Maple Bay, BC, Canada
The guy who owns the assets now, DMI, Inc, is a bit sketchy, and I've heard stories of poor service from him. He's basically selling off what remains of the part inventory, and doing some repairs. Reviews have not been super.
I did run across the DMI website, but it didn’t look like a site for marine instruments. It had a dog and a guy on a Harley. It seemed more like a hand made fan site type web page than one of a business.
I had a superb experience with DMI although it was quite some time ago. Mike, dig deeper, don't just stop at the first page...
Since Datamarine is no longer a thing, who then makes gauges similar to these? They are using a 4” hole in the cabin.
...because you'll learn they make replacement instruments, too.
 
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Feb 18, 2022
440
Catalina 36 Port Orchard
I had a superb experience with DMI although it was quite some time ago. Mike, dig deeper, don't just stop at the first page...

...because you'll learn they make replacement instruments, too.
Well by the look of the website they say a lot on one page, then the products page shows one small gauge that’s Victor or something like that, and no Datamarine products. There is also a link to another hardware site that seems to be run by the same guy that looks just as home made and it also doesn’t have much on it. First impressions say a lot, and right now I’m not impressed. I think my chances are better with a new port lite or a repair.
 
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Oct 26, 2008
6,200
Catalina 320 Barnegat, NJ
I had the DM Corinthian instruments on my Starwind and they worked beautifully after I was able to buy new transducers for both the speed and depth from DMI, but that was in 2005. When I sold the boat in 2019 the instruments worked beautifully still. When I added the B &G/ AIRMAR instruments and a single transducer for all functions, in 2018, I simply added the new instruments and left the DM instruments in place for back-up. I had to buy a new paddle wheel along the way and it looked like there were no more transducers available at the time.
 
Feb 26, 2004
22,888
Catalina 34 224 Maple Bay, BC, Canada
and no Datamarine products.
Did you click on the products link/tab? IIRC, it has gauges to fit existing holes. DMI Marine, Inc. - Products Information

If you don't like the instruments, then fine, but don't knock the vendor's products, which do exist, if you don't look at the whole website, tiny as it is I think his text explains stuff quite well. I am glad to see he's still in business, nice fellow.

Under the Parts tab is this:
We have a complete inventory of DMI Marine (Datamarine® compatible) parts and accessories. Check the part and picture below for best match. More parts in stock, call for information.

Don't know what more you need. Are we looking at the same website.

In any event, your boat, your choice. :) For jviss, this phrase means "you have options." :)
 
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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
I really love Datamarine products, and think of them as I do my girlfriends from when I was 17, 18, 19 years old. :)
 
Apr 22, 2011
895
Hunter 27 Pecan Grove, Oriental, NC
I replaced the Datamarine depth and speed instruments on my Hunter after a year or so trying to get them to work. I bought a used Datamarine unit on E-Bay that had a faulty screen and used my old screen in the e-bay one. It stopped working, so I gave up on my old instruments.

The DMI replacement instruments were about $500 each not including the transducers. Compare that with a new Raymarine depth display with transducer for less than $500. The Raymarine unit has a bright large screen that is much easier on the eyes. Or if you want speed and depth, I would go with a dual output transducer as Scott suggested.

I installed a 4" speaker in place of one of the Datamarine instruments round cutout. Makes it easier to listen to the vhf in the cockpit.
 
Apr 8, 2010
2,021
Ericson Yachts Olson 34 28400 Portland OR
Many years ago I replaced our boat's three OEM Datamarine instruments. Since the holes in the bulkhead were a half inch larger in diameter than the Raymarine instruments going in, I reduced the old holes by cutting out a ring of frp and epoxying it into each hole. The bezel on the new instruments covered the work that I did.
The upgrade was invisible.
 
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Feb 18, 2022
440
Catalina 36 Port Orchard
Did you click on the products link/tab? IIRC, it has gauges to fit existing holes. DMI Marine, Inc. - Products Information

If you don't like the instruments, then fine, but don't knock the vendor's products, which do exist, if you don't look at the whole website, tiny as it is I think his text explains stuff quite well. I am glad to see he's still in business, nice fellow.

Under the Parts tab is this:
We have a complete inventory of DMI Marine (Datamarine® compatible) parts and accessories. Check the part and picture below for best match. More parts in stock, call for information.

Don't know what more you need. Are we looking at the same website.

In any event, your boat, your choice. :) For jviss, this phrase means "you have options." :)
Yes I did look, and no I didn’t see what I was looking for. I seen Phoenix instruments, which look good, but we’re not what I was looking for. I was hoping to find NOS or refurbished DM instruments and or documentation at least. I said as much in my first post. I didn’t realize when I first went to DMI’s website that it was going to be all that’s left of Datamarine. I figured it was a home brew website for someone who liked fixing these instruments. I’m going to have to see if what I have even works, and that won’t happen for a while. I don’t dare try to remove the transducers to clean them at this point and hauling out won’t be for a while yet.

Thanks for all who have answered, you have given me much to consider moving forward.
 
Oct 26, 2008
6,200
Catalina 320 Barnegat, NJ
Yes I did look, and no I didn’t see what I was looking for. I seen Phoenix instruments, which look good, but we’re not what I was looking for. I was hoping to find NOS or refurbished DM instruments and or documentation at least. I said as much in my first post. I didn’t realize when I first went to DMI’s website that it was going to be all that’s left of Datamarine. I figured it was a home brew website for someone who liked fixing these instruments. I’m going to have to see if what I have even works, and that won’t happen for a while. I don’t dare try to remove the transducers to clean them at this point and hauling out won’t be for a while yet.

Thanks for all who have answered, you have given me much to consider moving forward.
I think it hasn't been clear what you are having trouble with. Are the instruments not working or is it the transducers that you think are the problem. If it is the instruments, do they get power or are they just dead? You can always disconnect the instruments and send them to DMI to be evaluated or fixed if you really want to salvage them. If it is the transducer cores, you can get a plug and remove one easy enough. It's not a big deal to remove the ducer core and put a plug in. I removed them and put them in every fall and spring with the boat in the water (the travel lift straps will damage the paddle wheel if you leave the core in during launch). I bought a plug from DMI and I used the old depth core for a 2nd plug (I simply cut off the cable). As long as the o-rings are good, you will have no leaks. The ducers don't let water in until you pull the cores past the o-rings - you can pull the pin off and relax, the ducer isn't going to blow off and the boat isn't going to start filling with water. Have the plug ready with some lubricant on the o-rings so it slips on easily. You don't have to panic - you will only get a little water in the boat - it looks a little alarming but it's really not. Only if you are really inept will you even get a few gallons of water in the boat, and that would be meaningless anyway. You would have to be just a complete incompetent to put your boat in danger of sinking.

The web site shows the dummy plug for $15. It also shows a couple of speed transducer cores (SX-120 & SST-109 - they pretty much look the same to me) for a reasonable price. They both look very similar to the one I had for my corinthian unit. DMI will tell you which one is your replacement. You can also get the paddle wheel kit, which I bought on one occasion.

It's not clear what you are intending to do ... you may be able to get those up and running again with products and assistance from DMI, but then again, it may be best to get modern instruments. You may be able to utilize the existing holes through the hull. You may prefer to plug them permanently with fiberglass and start new.

You should be able to get a plug or plugs and pull them out while the boat is in the water. You should be able to relay all the info needed by DMI just by looking at the instrument model. If your ducers are not functioning, then DMI should be able to tell you if they have compatible replacement (cores or the entire thru hull) and you can simply leave the old ones in place until the new ones arrive. Obviously, if you have to replace the thru-hull, then you will need the boat out of the water (but the cores are easily replaced in the water).

But if you are still exploring your options, you may as well figure it all out while the boat is out of the water.
 
Feb 18, 2022
440
Catalina 36 Port Orchard
I was originally looking for documentation on the units I have to make sure I have the proper connections and what have you. I don't trust the previous owner's electrical skills. I have found too many wires twisted and taped together in various areas of the boat for various systems. I was going to power the units up independent of the rest of the boat so I can know if they need to be replaced or repaired. I do like their look and want to keep them.

I have been working on a wiring plan for the boat. I will be replacing the cabin lights with LED, and I would like to get some more modern electronics and a new switch/breaker panel as well. I have been testing the various electrical things in the boat. I have also been removing the 110v stuff as most of it is wired with household equipment and not grounded.

Why I am not sure about pulling the transducers at this point due to the growth on the bottom of the boat. It has been sitting for 15 years unattended. The marine life I have so far been able to scrape off has been really easy to get off but I don't want to take a chance of something preventing it from going in all the way or getting stuck somehow. The underside of my boat is currently a mess. As for the transducer being hit by a lift strap, I think I will be good in that department, my speed transducer is in the bilge facing sideways, I doubt a lift strap would get anywhere near it. My depth transducer is next to the engine so that one may be in trouble.