The byline on Chuck Husick’s long-running column, Technotalk, notes that the author is a sailor, pilot, engineer and former president of Chris Craft Boats. But, this simple “bio” just does not do him justice. Chuck has been providing BoatU.S. with the straight scoop on how things work and why things do what they do for years. Now, rather than squeeze him into a column we’ve decided to let him go full sail in a new feature we’ll simply call, Ask Chuck.

Rather than being limited to Technotalk’s single topic format, “Ask Chuck” will encourage a two-way communication and an on-going dialogue between Chuck and BoatUS Magazine readers on a wide array of questions involving gear, the latest equipment and the best technology for use on your boat.

If you are looking for a credible expert to guide you through some of the more complex and arcane aspects of boating, Ask Chuck is your answer. We invite your questions by e-mail. Address your inquiry to AskChuck@BoatUS.com. We look forward to hearing from you.

Q: This summer I lived aboard my sailboat. I still only managed to get out sailing on weekends, but since I would be sleeping and spending a lot of time aboard thought it would be a good idea to make sure I had a smoke and carbon monoxide detector.

I opted to get some from the local hardware store. The CO detector had a nice digital readout, and seemed to work properly. When I used my alcohol stove, the readings went up slightly. Everything seemed to work fine for most of the summer until strangely it set itself off and read high numbers once or twice. I thought it just failed completely and I was prepared to simply chuck it out. To my surprise the readings cleared up when I took it outside. As far as I can tell, there were no sources of CO. No motors running (mine or nearby boats) nor any stoves. I'm wondering if these detectors might be sensitive to high heat/humidity summer conditions or fumes coming off evaporating alcohol or something like that? Any ideas?

Iain Galloway
Cheshire, CT

A: Although I can't be certain, I believe your CO detector was reacting to the high humidity condition on your boat. Household detectors are intended for use in the relatively low humidity found in homes. They will also alarm when in the presence of mixtures of various outgassing materials, including some of the resins and adhesives used in boatbuilding. You will be well served by purchasing a detector specifically designed for marine use.

Q: I have twin Crusaders (454XL) with Holly four-barrels. These came with my 35 Mainship in 1993. I have never had them overhauled with only 600 hours on the motors/carbs.

The problem is when I start the engines, they settle down to 600 rpm. I take a short cruise and as I idle back to the 600 rpm, they stay above 1,000 rpm. When I attempt to jockey the throttles back and forth with the intent to bring them down, they stay at the higher rpm. If I turn the engines off and wait (say 30 seconds or so) and restart them, all is fine at 600 rpm.

I have considered rebuilding both carbs over the winter but can't put my finger on the problem. I have pulled the flame arresters and worked the chocks back and forth. I tried to adjust the idle but nothing works. I have oiled and worked the spring attached to the flapper - it seems to work normal. As the motor warms up and the flapper opens up slowly, it seems to be fine but after a ride, it fails and goes back to the high rpm until I turn it off and restart the motors. The wires connected to the chock are fine. Do you think it is the shaft holding the spring that needs cleaning or the whole carb?

Robert Kardys
Windsor, CT

A: I have never had to repair or rebuild the four-barrel carburetors on your engine; however your description of the problem is a classic example of an age/corrosion-induced problem. Since you don't mention having used any type of carburetor cleaner, I'll assume that no attempt has been made to clean them during the past 14 years.

Since the engines run well and the only problem they present is the high idle, I would not try to rebuild the carburetors until I had cleaned them as thoroughly as possible while they are on the engine. I would try using a cleaner such as CRC Carb & Choke Cleaner. Since you will be working on the engine without the flame arrestor, please be sure to have the engine compartment access hatch open and the compartment well ventilated.

Q: My boat is a 26-foot Grady White 1995 that has a freshwater system including a hot water heater. When I turn on the hot water faucet, the water comes out with a slight odor and a white milky color. It does not come out milky out of the cold water faucet. I was told to put Clorox bleach in and to let it stand for a couple of days and then run it through the hot water system. It did not clear up the problem. Do you have any suggestions?

Bill Fallon
Neptune City, NJ

A: From your description of the problem, it appears likely that the cause of the malodorous and milky-colored water is due to a condition within the water heater. The odor problem may be caused by the presence of vegetable matter in the water, which decays during the time the water is retained in the hot water heater. It is possible that the tank itself is deteriorated or, since it is not yet leaking, that the tank's magnesium anode has been eroded to the point where it is no longer effective. The anode is usually attached to the hot water outlet fitting of the tank and can be examined by removing the fitting.

However, you mention that your boat is a 1995 model and therefore it is likely that the water heater has been in service for about 12 years. Depending on the condition of the tank, you may wish to proceed with care if you decide to inspect the anode; on occasion, removing the fitting from the tank can cause damage to the threads into which the fitting is fastened, necessitating replacement of the tank.

Q: I have an 18-foot fiberglass bowrider (Scout 2005) that has an odor in the bilge. I have tried soaps and a bleach/water mixture which I sprayed in every area of the bilge that I could get at or those that drain into the bilge. The bleach mixture worked the best but the odor and black algae came back. The boat was bought used in Florida and brought to New Jersey.

Do you know of anything that can eliminate this algae and odor?

Paul Miller
Manasquan, NJ

A: Based on your description of the problem in the bilge area of your boat, I will assume that the bilge is enclosed and not well ventilated. I believe the problem you have noted, a malodor and a black deposit, is most likely mildew, a mold, specifically a fungus, not an algae, which is a plant that requires light to support photosynthesis.

Mildew fungus spores, which are invisible to the unaided eye, are always present in the air, often at concentrations in excess of thousands per cubic foot. The fungus does not normally grow in well ventilated spaces where the normal atmospheric level of ozone, 20-40 parts per billion, is sufficient to prevent its growth. However, the ozone content of air in an enclosed space will decrease to essentially zero after an hour or two, after which the fungus will begin to grow. This is the reason that mildew is often found growing in bathrooms and particularly in shower stalls where there is poor air circulation. Cleaning with bleach kills the fungus but cannot prevent its regrowth.

You can eliminate the problem in the bilge of your boat by ensuring a flow of air through the space by providing two or more air vents. Boat owners whose boats have access to shore power may install small fans to provide a forced flow of air. A solar-powered air vent can be used to good effect if a way can be found to install it where it will be exposed to sunlight and will not interfere with crew movement.

Battery - or AC-powered ozone generators that restore a normal atmospheric ozone level, about 20-40 parts per billion, can also be very effective in eliminating mildew.

Q: My new MerCruiser 5.0 EFI specifies a gradual 20-hour break-in period, where the engine is only gradually exposed to higher rpm. Presumably to season or temper the cylinders. I am a fanatic when it comes to proper engine maintenance and I hope to keep this boat for many years and long hours.

When I purchased my new boat, the dealer retrofitted the new motor with a sealed coolant system. The mechanic failed to tighten a clamp. As a consequence, the coolant escaped and in the first three minutes of engine life at the recommended rpm, the engine overheated and the automatic safety system kicked in and shut off the engine. The temp reading was 200 degrees at shutdown.

My boat dealer has assured me no harm was done and my long-term fuel and oil efficiency will not be adversely affected. Do you agree? Something about this assurance does not make sense to me, since MerCruiser goes to some length to insist on avoiding overworking an engine in its virgin 20 hours.

Is there anything I can do, other than document the incident? My concern is that any future performance problems will not be directly traceable to this incident, if in fact it caused any future problems.

Bruce Tait
Nova Scotia, Canada

A: Based on your report that the overheat alarm sounded within a few minutes of operation, I believe it very unlikely that any damage was done to the pistons, cylinder walls or valves. The remainder of the engine is largely cooled by oil and would not have experienced any overheating in the operating time you report. The alarm triggered the automatic shutdown as soon as the coolant temperature exceeded the limit.

I base my belief that you should see no future problem on the fact that the high sensor temperature was the result of total or near-total loss of coolant and not due to failure of the cooling system to remove heat from the engine. If it were my boat, I would accept having the engine cooling system restored to proper operating condition.

I suggest that once you have satisfied the recommended 20-hour limited rpm period that you run the engine at full power for a number of five-to- 10-minute periods both to evaluate the behavior of the cooling system. Longer periods of close-to-full-power operation will be needed to fully seat the piston rings.

Q: When I purchased my current boat (2003 Four Winns 240 Horizon) I was told that operating the boat with the switch in the "both" position was not recommended because it wouldn't properly charge both batteries. The theory goes, according to my sales technician, that if you have one charged battery and one in need of charge that the alternator/voltage regulator would detect the charge of the fully charged battery and therefore would not send a charge to the weak one. Seemed reasonable to me but this seems contrary to the comments in your last column.

I always run my boat on either 1 or 2 (alternating between the two on each outing) and almost never on both. This, in theory, guarantees that I'm fully charging the battery in operation (as well as ensuring it will start the motor as you mention in your article).
So, more fuel for the fire!

The Carrs
Hingham, MA

A: In my opinion it is best to start the engine on one battery to check its actual ability to provide the high starting current demand and then switch to "Both" to recharge both batteries.

For more of Chuck Husick's insights, go to BoatUS.com and look for Chuck Husick under Resource and Reference.



© Copyright BoatUS Magazine January 2008