exhaust alarm

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Ron M.
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Joined: Feb 5th, '05, 11:32
Location: CD30c Harwich,Ma.

exhaust alarm

Post by Ron M. »

I completed a repower last spring and have been pleased with the results. I am now considering installing some type of exhaust temp. alarm/monitor to indicate a problem before the waterlock muffler melts.
I've seen 2 types, one with a sensor that is installed into the exhaust hose and the other is a band that goes around the hose. Both are wired to a small panel with led's and a buzzer.
Does anyone have any experience with these and could share some insight/pros-cons. ? thanks
________
HEAD SHOP
Last edited by Ron M. on Feb 11th, '11, 05:43, edited 1 time in total.
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Parfait's Provider
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Location: CD/36 #84, Parfait, Raleigh, NC
berthed Whortonsville, NC

No Experience

Post by Parfait's Provider »

Ron,

I have no experience, but my engineer's gut says that anything inside the exhaust hose is fraught with potential problems even if it would initially be more sensitive to temperature fluctuations.
Keep on sailing,

Ken Coit, ND7N
CD/36 #84
Parfait
Raleigh, NC
Oswego John
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Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1

Rise In Exhaust Temperature

Post by Oswego John »

Hi Ron,

I have to agree with our resident engineer. (Hi Ken)

Since it is lack of cooling water that is the principal cause of overheating in a wet exhaust system, I think that maybe it is worth considering the monitoring of the cooling water flow.

A N/O flow switch placed in line with the cooling water supply would give you the same warning without any of the related risks of monitoring the exhaust gas temperature.

Without water flow, the switch would close and activate the alarm system.

Just a thought
Good luck,
O J
Ron M.
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Joined: Feb 5th, '05, 11:32
Location: CD30c Harwich,Ma.

Post by Ron M. »

Thanks for the input gentlemen.
O.J. could you be more specific on the type of switch you mentioned. I'm not clear about your recommendation .
________
VAPIR ONE REVIEW
Last edited by Ron M. on Feb 11th, '11, 05:43, edited 1 time in total.
Buck
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Location: CD30 1979 BUSTER Fairhope, Al. previous boat CD 28
previous CD28 23 yrs

Post by Buck »

what did you repower with? Would like to hear some specifics/pitfalls for future reference...the newest cd 30s are over 20 years old now! Thanks Buck
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bottomscraper
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Location: Previous Owner of CD36 Mahalo #163 1990
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Sailors Solutions Flow Switch

Post by bottomscraper »

I don't have one but I did see this one on the Sailors Solutions web site while looking for something else:


http://www.sailorssolutions.com/index.a ... Item=FS200
Rich Abato
Nordic Tug 34 Tanuki

Previous Owner Of CD36 Mahalo #163

Southern Maine
http://www.sailmahalo.com
Oswego John
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Joined: Feb 5th, '05, 20:42
Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1

Water Flow Switch

Post by Oswego John »

Hi Ron,

There are dozens of types of flow switches that are used to detect flow or absence of flow of liquids and gasses in a closed system. It is easier to understand the concept of how they operate if we stick to the water flow switch. After all, that's what we want to monitor.

There are several types of flow switch designs, electric, electronic and mechanical. The most common type is a shell or case which contains in it a paddle or other type sail that reacts when moving liquid pushes the paddle from it's resting place.

When the paddle that is immersed in water is moved by the flow of water, it activates an electrical switch on the outside of the switch case. There is an option to wire the switch in N/O (normally open) or N/C (normally closed) mode.

My first introduction to flow switches, which might give you a better idea of their purpose, was wiring them into fire alarm circuits, both locally and notification to the fire house.

At any hour of the day or night, whenever a sprinkler head would sense unnatural heat, it would pop open and discharge water on the fire. The water that would flow from the main supply to the sprinkler head would activate the paddle within the flow switch. The paddle would close the N/O switch and activate local alarms as well as notify the fire station.

A flow switch inserted in the engine cooling supply could be wired to the console to warn you of lowered or total lack of water flow. Some switches have variable flow settings.

There are so many links to so many makes and models of flow switches, I recommend that you type in key words "Water Flow Switch" and see whats available to suit your purpose.

Feel free to ask for more info.

Good luck in your quest,
O J
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Parfait's Provider
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Thermocouple

Post by Parfait's Provider »

A thermocouple like that from an indoor/outdoor thermometer could be taped to the cooling water hose ahead of the mixing elbow to tell you what the temp of the cooling water is.
Keep on sailing,

Ken Coit, ND7N
CD/36 #84
Parfait
Raleigh, NC
Ron M.
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Joined: Feb 5th, '05, 11:32
Location: CD30c Harwich,Ma.

Post by Ron M. »

Thanks Rich, I hadn't seen that one.
OK - O.J. appreciate the explanation. Will look into it further.
Ken. thanks.
Buck.......Volvo D1-20. Be prepared to replace trans, shaft, exhaust system, and prop.May as well throw in a dripless shaft seal.
I did the job myself with some help from a knowing friend. Get the old engine out and the new one in the boat.You can measure all day but really learn nothing until you place the beast in it's home. Have a lifting device as you will need to put it in place and remove it 4 or 5 times. I had to adjust my stringers a bit but not a big deal. Patience is key.
Engine placement took 2 days with some downtime for grinding and waiting for epoxy to dry.
Hooking up systems took the best part of a week.
________
Los Angeles Dispensaries
Last edited by Ron M. on Feb 11th, '11, 05:43, edited 1 time in total.
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Parfait's Provider
Posts: 764
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Location: CD/36 #84, Parfait, Raleigh, NC
berthed Whortonsville, NC

Sound Like a Pro

Post by Parfait's Provider »

Ron,

It sounds as if you had at least as much luck doing it yourself as my professionals did. We tried every way to grease the skids with a Robinhood pan and consult and it was still touch and go with them almost scrapping the pan at their expense just to get the job done. In the end it worked out, but it definitely wasn't a simple matter of measuring twice and cutting once, it was more like measure twice, cut once, set in place (measure again), cut again (or fill), and again, and again.
Keep on sailing,

Ken Coit, ND7N
CD/36 #84
Parfait
Raleigh, NC
Ron M.
Posts: 1037
Joined: Feb 5th, '05, 11:32
Location: CD30c Harwich,Ma.

4 foot broomstick

Post by Ron M. »

Ken,
Forgot to mention......get a shaft, or straight substitute long enough to allow aliening the mounted shaft coupling with the shaftlog, cutlass bearing. This is where you need to measure........once you can 'see' what needs to be done you're almost home.
________
Chrysler Dr Platform History
Last edited by Ron M. on Feb 11th, '11, 05:43, edited 1 time in total.
darmoose
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Location: 1979 CD30K, hull#122
Mystic Rose

reply/ question

Post by darmoose »

ron,

havent talked with you since you finished your repower. sounds like it all went well. i know it is a job, though.

what size and pitch propeller did you end up with?

darrell
mystic rose
Ron M.
Posts: 1037
Joined: Feb 5th, '05, 11:32
Location: CD30c Harwich,Ma.

Post by Ron M. »

Hey Darrell, and thanks for all the information you helped me with.
I should know exactly the answer to your question........I think it is a 13/12LH........I'll have to check
________
Mercury Mariner
Last edited by Ron M. on Feb 11th, '11, 05:43, edited 1 time in total.
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mike ritenour
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Sensors and a thermal map

Post by mike ritenour »

IMHO, the safest bet is to have an instrument that monitors both the intake water flow(s) and the exhaust temperatures.

Location of the sensors is the key. On the perfect boat, I'd like to have a sensor on my intake strainer, one just down stream of the impeller and one on the exhaust elbow.

As if too much data isn't enough, I bought one of Radio Shack's infrared thermometers a few years ago. What a handy gadget! I think it cost a whopping $29.00.

Although not a "system" to monitor the water temp and exhaust gases, I am able to determine the surface temperatures of various areas on my engine along with the intake water temperature.

Typical measurements include intake water temperature, oil,head, exhaust, tranny and stuffing box temperatures.

Over the years I have obtained a good thermal image of my engine and find the monitoring effort an easy and interesting endeavor in trying to understand and serve my iron mistress.

Rit
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