Nigel Calder Answers Question - Ask Sail

THE EXPERTSNigel Calder is an expert on boat systems and diesel engines. Don Casey has written many books and articles on marine maintenance and repair. Tim Bartlett is a former Royal Navy officer who is an expert in radar and electronics systems. Gordon West is a communications expert and a specialist in radio communications.DIRTY GROUND
Author:
Updated:
Original:

THE EXPERTS

Nigel Calder is an expert on boat systems and diesel engines. Don Casey has written many books and articles on marine maintenance and repair. Tim Bartlett is a former Royal Navy officer who is an expert in radar and electronics systems. Gordon West is a communications expert and a specialist in radio communications.

DIRTY GROUND

Recently we had trouble starting the diesel engine aboard our Nordic 40. Although all the lights and other electrical equipment aboard worked fine, whenever I touched the starter button, the starter motor hesitated at first then sped up. We checked the batteries and found that they were eight years old, so we decided to replace the type 27 starting battery and the large house battery. These were hooked in parallel and had individual on/off switches.

We installed two dual-purpose type 27 batteries, also in parallel, but the starter motor continued to hesitate and then sped up again to start the engine. There were also one or two times when nothing happened at all when we pressed the button. Finally, my partner saw a flash in the vicinity of the battery ground and the engine. We sprayed some electrical contact cleaner on the ground connection, and when we pressed the starter button again the starter motor had no hesitation and the engine started up quickly. Since there were no additional sparks or flashes, we don't know what caused the flash. Could it be a loose ground cable, or is there something else we need to troubleshoot?MARK KARWOWSKI SAN FRANCISCO, CALIFORNIA

NIGEL CALDER REPLIES:

I'd say it's that pesky ground strap. If corrosion is allowed to occur at the point where the ground strap attaches to the engine block, that will almost certainly lead to starting problems of the sort you experienced. No matter how hard that strap may be to access, you must remove it and clean its terminal and the mating surface opposite it on the engine block. Use fine-grit wet and dry sandpaper or something similar. After you have reattached the connection, give it a good shot of corrosion inhibitor or slather it with Vaseline. That should keep you cranking happily for several years. Inspect the connection visually at least every six months to make sure its performance is not being degraded again by corrosion.

CIRCUIT BREAKER

Where can I get a galvanic isolator of the sort you mentioned in your excellent piece on wiring a boat for shore power? Also, the circuit you described in that piece doesn't seem to provide ground-fault protection either for the battery charger or for other branch loads, such as the water heater, which would be hard-wired to the CB panel. Shouldn't one install a Ground-Fault Circuit Interrupter (GFCI) outlet near each device and then plug them in just as you would a galley blender?GENE CRAMER, MILWAUKEE, WISCONSIN

DON CASEY REPLIES:

You can find galvanic isolators in both the West Marine and Defender Industries catalogs, and I'm sure your favorite chandlery can also get one for you from one of any number of manufacturers.

To answer your second question, ground-fault protection is less of an issue with hard-wired appliances such as a battery charger or a water heater, but you would not be wrong incorporating it into your shore-power wiring. The easiest way to do this is to power these appliances through a GFCI breaker. Although a long wire run could possibly lead to enough capacitive coupling to trip a single GFCI, that probably would not be a problem because of the relatively short distances between outlets on a boat. One GFCI should protect several downstream outlets that are on the same circuit without leading to trip problems.

Related

Shelly-forward-last-day

Charter Advice for First-Timers

Never chartered? No worries. A vacation under sail can be the most memorable time of your life. That said, it also pays to be prepared by doing some reading, building your skills and listening to what the experts say. First and foremost, not all charter grounds are created ...read more

HugoBoss

Video: Vendeé Update

Last week Alex Thomson (Hugo Boss) led the fleet across the equator. As one of the class' top sailors who's been on the Vendeé Podium twice, it seemed possible that Thomson was going to grab an early lead and hold on to it all the way around the world. But early on Saturday, he ...read more

AdobeStock_229409051

Chartering Again for the First Time

It’s been a rocky road of late for the charter industry, especially here in the Western Hemisphere. First came hurricanes Irma and Maria in the Caribbean followed by Dorian in the Bahamas. There has also, of course, been the coronavirus, which burst into global prominence ...read more

01 LEAD cedaryachtclub_onedesign18_hike

An Interview with Ayme Sinclair

In recent months, US Sailing, like many organizations, has been taking a closer look at diversity to ensure it’s doing the best job it can of introducing people from all backgrounds and ethnicities to the sport. As part of this effort, this past summer it organized an online ...read more

125768940_10222759720523627_5373654001582879638_n

US Sailing Presents Adaptive Sailing Panel

On Tuesday, November 24, US Sailing’s Leadership Forum will present the latest panel discussion in their Diversity, Equity and Inclusion series. This event will focus on adaptive sailing and provide practical recommendations for organizations looking to expand their adaptive ...read more

02-IMG_5971

A Carbon Neutral Circumnav with Jimmy Cornell

Historic anniversaries have always held a special fascination for me, especially if they mark a significant nautical achievement. In 1992, on the 500th anniversary of Columbus’ would-be voyage to India, I organized a transatlantic rally that followed the historic route of the ...read more

DJI_0068

SAIL Podcast: Jimmy Cornell’s Carbon-free Circumnav

In this episode of Point of SAIL, Principal Editor Adam Cort talks with bestselling author and pioneering bluewater sailor Jimmy Cornell, who set out November 19 on yet another circumnavigation aboard a newly designed, carbon-neutral Outremer 4Zero catamaran. The voyage, which ...read more

emirates-600x

Emirates Team New Zealand Splashes the last of the AC75s

Emirates Team New Zealand unveiled its second-generation AC75 yesterday, joining the other three America's Cup teams with boats in the water. In just over 100 days, this boat will attempt to defend the Cup for the Kiwis, but there's plenty of racing between now and then, with ...read more