Knotmeter for 1978 H30C

Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
image.jpeg
Just wondering if older Knotmeter transducers might be available for our older boats. My under hull, thru-hull, paddle wheel was compromised/broken by the lift out Marina last October. I wanna keep this boat as original as possible, and clearly I don't care too much about speed with today's GPS and stuff...but if I can get the old gear to function that would be, as the Admiral puts it...TITS! From inside the forward port settee within the V-berth, the transducer looks like this image above. Thanks in advance for any direction provided.

Wayner
 
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May 12, 2004
1,505
Hunter Cherubini 30 New Port Richey
I understand. I'd like to keep the old boat as original as possible. Alas, time is not on our side and speed isn't so much an issue these days. But, as the Admiral puts it, if I can get the old gear to function as it did in the past...TITS.
 
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kito

.
Sep 13, 2012
2,011
1979 Hunter Cherubini 30 Clemmons
Are you sure that is original to your boat? No sense on trying to keep it original if indeed it isn't original to start with. My 79 didn't have a paddle wheel.
 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
Hi Guys, thanks for the feedback. I doubt that the transducer/transmitter is original equipment, but I may never know. I tried the link to Moor Electronics, and the web page said that they have closed their doors as of November 2015. Please see the announcement below.
Important Announcement!
Moor Electronics, which began its line of marine instruments 30 years ago, will close its doors for good in November, 2015. We would like to thank our customers for all the support they have given us over the many years.
Over the last few years, Moor Electronics has faced heightened competition, increased costs, pressure from vendors and waning consumer spending.
Facing the loss of our lease, coupled with the cost of moving the manufacturing plant, slow marine market and consumer worries and economic factors proved insurmountable.
While Moor Electronics, maker of the Sub-Troll 900 and Electro Marine Systems "EMS" line of instruments will cease operations, any repairs or parts you need may be obtained from the companies listed below. They are independent and not affiliated with Moor Electronics. Big Blue Enterprises is a company we contacted to ensure our customers have continued support for their Marine Instruments. EsgDirect.com has been an online dealer for Moor for over 16 years.
If you were a dealer of Moor products and have stock on parts or new units, we can add you to the list below.


The Moor website did provide a link to another company that is distributing older MOOR inventory and some knotmeter replacement parts for our 30+ year old vessels. That company is Esg Direct: http://esgdirect.com/sailing.html

The transmitter looks to be the same model as mine, so I'm gonna attempt to order the replacement assembly, sans instrument head. I appreciate the link Denny!!! :dancing:
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
most of these transducers operate the same and as long as you respect the wiring and voltage requirements will work with any control head you can rig an electrical plug for. 5 volts in and a ground. The transducer takes the 5 volts and using a magnet in the paddle wheel and a wire coil in the plug produce a voltage wave form that has voltage spikes or dips (negative spikes, wires are reversed for this) which the control head counts as it keeps time. Time * count * calibration factor = distance. since the paddle wheel will rotate in either direction and produce spikes in one and dips in the other the real question is what is the control head pin out. most transducers only have 2 wires so you can't screw it up. Some newer transducers have a temp sensor in them. Those wires are easy to determine as they will not show a 0 ohms resistance like the wire pickup coil for the paddle wheel
 
Feb 8, 2014
1,300
Columbia 36 Muskegon
These items are owner or dealer installed. No such thing as "stock". Parts do show occasionally show up on eBay or the salvage shops. People are replacing these all the time they have to go somewhere. Hopefully they don't all end up in the trash.
If there are any electronics installers in your area you could try them, maybe they just removed one or you could put dibs on the next one.
 
Jun 4, 2004
392
Hunter 31 and 25 and fomerly 23.5 Stockton State Park Marina; MO
[QUOTE="BlowMeAway, post: 1284971, member: 133146"

The transmitter looks to be the same model as mine, so I'm gonna attempt to order the replacement assembly, sans instrument head. I appreciate the link Denny!!! :dancing:[/QUOTE]

Looks like esgDirect will get you fixed up; if not then send me a PM and we can make arrangements for me to send you my old paddle wheel. I swapped mine out with a new complete Raymarine system on my H25 rebuild. I don't know if any of the old system worked, but the paddle wheel assy. looks OK.
 
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Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
I swapped mine out with a new complete Raymarine system on my H25 rebuild. I don't know if any of the old system worked, but the paddle wheel assy. looks OK.
Hey Dennis, thanks. I'll keep that in mind if this plan doesn't work out. I did place an order yesterday and received confirmation from EsgDirect, just waiting for the shipping confirmation to arrive. I ordered the whole transmitter and cable assembly. I was going to just order the paddle wheel, but wasn't so sure of similarity to my broken wheel. I'll check back in with you and SBO once the unit gets installed in the hull. My boat's on the hard in a cradle so no worries about replacement.
 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
The alternative "Wet" replacement looks a little scary to me, especially if there's any variation in dimension:

 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
image.jpeg
image.jpeg

Crap, this happens to me all the time! I finally got out to the boat today and the top of my list was to install the new paddle wheel transducer for my S.R. instruments, model KL-5, SN368, knotmeter. The part that I believed would fit, based on conversations with EsgDirect.com, was a U25K Moor "Red" Complete Replacement Transmitter. It didn't fit. The diameter of the replacement was approximately 0.25" too wide in diameter. If anyone has an original scrap unit around all I really need is the paddle wheel. I will pay for the paddle wheel and the postage. Contact me by PM from this site. Thanks in advance.

Oh yeah, the caliper is in units of 0.01 inch.

Wayner the complainer!
 
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kito

.
Sep 13, 2012
2,011
1979 Hunter Cherubini 30 Clemmons
Welcome to my world. Instead wasting time, energy and money chasing the perfect replacement which will most likely be used, why not change your thru hull that has the correct bore for your new paddlewheel?. Better yet, 86 the darn thing, pull the thru hull and patch it. I didn't like the idea of having a 1/16" cross section o-ring failing and deciding between my boat floating or sitting on the bottom .
 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
Kito pal, I hear ya loud and clear! Yeah those gaskets are pretty thin. Unfortunately I don't have the where-with-all to clog up the no longer used through holes. If the boat was here at home, avoiding the one hour drive to the Marina, if I didn't have to work 50+ hours a week making a living, if I didn't have to maintain a house and large lot with trees, if my Admiral was better skilled in Fiberglass repairs, etc.....I'd have the best looking and fully functional craft at the dock.

At this point I just need a friggin' paddle wheel for this antique of a transducer. We're not making any new holes in the hull on this old girl...and I mean the boat, not the Admiral!
 

kito

.
Sep 13, 2012
2,011
1979 Hunter Cherubini 30 Clemmons
No new holes but enlarge the existing one for the new thru hull that will accept the new paddlewheel. I feel your pain. You don't want to haul out. I guess just keep looking for the right one. I got rid of mine and just going to use the gps for c.o.g speed. It's not effected by current etc.
 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
Kito, Thanks for understanding. I think it would be easier to drill a new thru-hull than enlarge an existing one. The only holes I've ever drilled (literally not figuratively) where with a hole saw, and most for door knobs. I wouldn't know how to enlarge an existing thru-hull...and I hate the idea of filing. These hulls are pretty damn thick. My neighboring on the hard '79 H30 owner told me the local boatyard charged him $600 per upgrade on his holes. He had three refitted.
 
Nov 30, 2015
1,343
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
Team, just ordered the correct transducer direct from SR Instruments. Should have tried that first, a little more thoroughly. I would never have found the Mariner Instruments section of the website based on their home page. Apparently they no longer Mfg these units, but keep some stock in inventory for the old tools. Currently SR instruments is mfg analytical scales. It was the brilliance of Mr. Dennis Kitchen who broke that web barrier for me. This is the site link he provided, I thought I'd share it with the forum:

https://www.srinstruments.com/sort/srmariner.php

Game over, thank you all for your inputs. :plus: