Features September 1, 1999 Issue

Corrosion-Resistant Bilge Pump Wire?

A periodic complaint we receive about electric bilge pumps in general concerns the wire leads. Actually, the gripes are three: the wire leads are too short, the gauge too small and the copper wire strands not tinned.

Recently we heard from a Practical Sailor reader with a different question about bilge pump wire. Here is what Donald Morda of Staten Island, New York, wrote:

“While installing a new Rule 2000 bilge pump, I stripped back the electrical supply wires and found what at first appeared to be corrosion of the copper strands. The powdery substance was slippery and could be snapped or blown off. Wiped clean of the powder, the copper strands were fairly clean and bright.

“I called Rule and was informed that the wires are treated with an ‘anti-corrosive powder.’ The powder was not identified. I installed the pump and had no problem soldering the connections.

“I have no complaint with Rule pumps. The one I replaced was running fine after four years and 6,000 miles. I just regard some vital things as periodic replacement maintenance.

“However, I’m still wondering what this anti-corrosive powder is. Should I lay in a supply of this wire? Is it more effective than tinned wire?

“For a mere two feet of wire, it couldn’t be cost…could it?”

Reader Morda thoughtfully taped to his letter a 4" sample of wire. Copper strands heavily dusted with some loose gray powder are encased in a reddish brown rubber or plastic cover. The powder can be snapped or blown free.

On the cover, in tiny white type, is EIS SU AWM VW-1 10SC. All of the lettering is plainly readable with a common magnifying glass.

Next: Some phone calls.

An engineer at S&J Products, a big wire maker in Chicago, said he had no idea what the “anti-corrosive powder” could be. “Never heard of such a thing,” he said, and added that if there were he’d take it as a matter of professional pride to know about it.

A spokesman for a big wire maker in Pennsylvania (which shall remain nameless) yelled into the phone, “Anti-corrosive powder…you’re putting me on…it’s talc,” and hung up.

Finally, having waited out the three-hour time difference between the East Coast and the West Coast, we called Ancor, in Cotati, California. Ancor is a very large manufacturer and supplier of tinned copper wire—many varieties—for the marine industry. (The West Marine and BOAT/U.S. catalogs are full of Ancor products.)

Dan Eddy, Ancor’s materials director, said that the powder undoubtedly is talcum (usually magnesium silicate), which is useful in the manufacturing process to lubricate the strands and make sure they fall into linear alignment with equal tension as the cover is applied.

He said such inexpensive wire is what is called “appliance wire” or “household wire”.

In fact, the “AWM” lettered on the wire means “Appliance Wiring Material”.

Eddy said wire bearing Ancor’s name is tinned, each strand, to minimize corrosion and electrolysis, and exceeds the standards of the SAE, ABYC and U.S. Coast Guard charter boat specs (CFR title 46). It also is UL-approved Type 3 wire, the latter meaning that it has many fine strands to enhance flexibility and resist failure because of vibration.

Then came a call to Rule, in Gloucester, Massachusetts. Because we don’t believe in “ambush journalism,” we identified ourselves and explained Reader Morda’s quandary.

The Rule spokesman said the powder is “silicone blocking powder”.

“If it gets wet,” he said, “it swells and blocks the water. None of our competitors have it. Novices often are confused when they see the powder.”

Silicone is a polymeric silicon compound with some water- and heat-resistant qualities. But being made of silica (the commonest form is sand), it seems unlikely that it will swell. It might be worth noting here that talcum powder and silicone are both basically silica.

Asked to explain what the lettering on the wire means, the Rule spokesman said they are manufacturer’s specifications, but that he did not know what the groups of letters mean. When asked for the manufacturer’s name, he said:

“I don’t know whether we want to do that,” and then said he would have a Rule engineer call and explain.

Three days later, the engineer called and said the powder was, indeed, “silicone blocking powder” and that the manufacturer of the wire is EIS, of S. Hadley, Massachusetts.

A spokesman for EIS, when reached via telephone, said the powder is “usually talc.” “Makes the wire easier to strip,” he said. When asked about anti-corrosive properties, he said, “Well…not really.”

He said the EIS lettered on the wire identifies the company, the SU has to do with sunlight resistance, the VW-1 concerns the cover’s fire rating, but that he did not know what the 10SC means. He declined to discuss wire prices, adding, “We’re an industrial supplier.”

For what it’s worth, 14-gauge Ancor stranded copper wire is discounted in marine catalogs for about 25¢ a foot. Untinned 14-gauge stranded copper wire sells in hardware stores for 15¢ a foot.

Both would be about 20% less if purchased in 100' reels; commercial bulk quantities must be even lower.

Although bilge pumps usually are wired with 16-gauge wire, we priced out 14-gauge because hardware stores rarely carry anything smaller.

Reader Morda: It’s just a guess, but considering that there is a pair of 30" wire leads on that $66 Rule 2000 pump, the company probably saved maybe 50¢ by not using tinned wire.

The Case of the Stripped Hose Clamp
A bit more than five years ago, in the July 15, 1991 issue, we published a short discussion about stainless steel hose clamps and their tendency to turn into lumps of corrosion.

At that time, we examined clamps made by Ideal, Murray, Wittek, DuPage, Tridon, Gold Seal, EK Mfg., Serratub (Italian) and EEZE. We checked them all—whether stamped, cast, wrought or annealed—to see which were austenitic, ferric or martensitic. These refer to different crystal structures. Stainless tableware is made of marstensitic metal. Austenitic is best for marine use. It is generally non-magnetic, though cast austenitic may exhibit some magnetism.

Only four passed the magnet test. Six failed. In each failure it was the adjusting screw that was magnetic. Those that passed were DPCs, the EEZE and the Gold Seal.

The conclusion was that being labeled “Stainless” did not necessarily mean that all parts of a hose clamp are stainless steel (or the same kinds of stainless) and that, for marine use, a magnet provides a reasonable, although not foolproof, check.

Subsequently, in the October 1, 1991 issue, we printed an admirabl y concise response from Joseph Weiner, marketing manager of the Ideal Division of Epicor Industries. His letter clearly explained how the clamp bands, screw housings and adjusting screws can be made of different grades of steel. He concluded with, “Cheap hose clamps are not good…good hose clamps are not cheap.”

This past summer, a PS reader named John B. Harvie, of Virginia Beach, Virginia, followed that advice when he set about to replace the hoses and clamps on the Universal 25 engine (circa 1984) in his Catalina 30.

“West Marine,” he wrote PS, “had 7/8” hose clamps, for $3.49 and $1.49, the difference being that the more expensive type has a thicker band, with nice rolled edges, and pressed, indented threads instead of punched out slots. On the expensive ones, the inside of the band is smooth, which seems like an advantage.

“My old ones were the punched-out type and I’m enclosing one to show how the band failed in a weakened area within the screw housing, which was encased in rust and corrosion. So, as replacements, I picked the expensive ones.”

Harvie said he intended, of course, to use two clamps to replace the singles originally fitted.

Two days later, another letter and another small package arrived from Harvie.

“Looks like I outsmarted myself,” he said. “Enclosed is one of the expensive hose clamps. The pressed-in threads stripped when I installed it. Well, back to the El Cheapos…”

Curious about what kind of torque it took, we whipped down to our local West Marine store and bought a few samples of both the inexpensive Norton clamps, which have punched out slots, and the fancier type. The latter bear the name AWAB. Both the punched slots of the Norton and the pressed “teeth” of the AWAB are pitched to fit the adjusting screw threads.

Both the Norton and the AWAB clamps checked out with the magnet.

In the workshop, we hunted up a torque wrench but then got chased out to a hardware store to buy two step-down adapters to get from the torque wrench’s 1/2" stud to 1/4" for the socket that fits the hose clamp adjusting screws. Finally ready, we secured a hardwood dowel in a vise and slipped a pair of clamps on it.

With a slot-blade screwdriver—a good one with a largish handle—we could not break either the Norton or the AWAB.

We moved to the torque wrench, which supplies a lot of leverage.

Starting with the 7/8" Norton, we took it up tight, and kept right on cranking. The band snapped (the screw housing failed) at 7-1/2 foot pounds.

Shifting to the AWAB, we tightened it up and continued to apply pressure. The threads flattened, again at about 7-1/2 foot pounds.

The experiment indicates that both types of hose clamps seem equally strong and that, unless you have powerful hands, it’s difficult to destroy new ones with a screw driver.

We know not what to say to John Harvie, certainly nothing sassy. He must have some arm.

Another reader added to the hose clamp saga.

“The sky is falling,” wrote Reader James H. Barnhill, of Raleigh, North Carolina. “Not quite, but aboard a boat some things are aggravating and just a little bit dangerous.”

“Here are three hose clamps I found while doing routine maintenance.”

Barnhill sent along the three hose clamps. There’s an “All Stainless” Ideal Combo-Hex; an Aero Sea 200, also “All Stainless,” and a Canadian-make Tridon, which doesn’t purport to be stainless.

All have stainless bands and screw housings, but as Barnhill pointed out, “The screws are non-stainless, and corroded.”

At that time, we commented that, because you apparently have about a 40% chance of getting hose clamps that won’t corrode, your only recourse is to carry a magnet to your chandlery and check both the band, the housing and the adjustment screw.

Because there may have been changes in the ensuing seven years since we last dealt with hose clamps, we may get a deluge of samples from manufacturers currently making all-stainless clamps. If we do, we’ll take note, but it won’t negate our magnet test suggestion.

For 56¢ Worth of Bolts
In the August 1, 1995 review of freshwater pumps, we said the best compromise incorporating low noise, good water flow and long, reliable service was the PAR-Max 4 Model 30630, a deluxe version with a corrosion-coated motor and a sealed pressure switch.

We also said that Par’s 36000-series pumps are 40-year-old designs worthy of honorable retirement. Familiar to thousands of sailors, Models 36800, 36900, 36950 and 36970 were, in their day, good pumps now superseded by more modern “wobble plate” pumps.

Reader Jeff Miller, of Simsbury, Connecticut, knows another reason to avoid at least some of the 36000-series pumps. With his letter to Gear Graveyard, Miller enclosed a couple of plated steel bolts from his 36800 Par, which had a leaky diaphragm.

“These bolts and two others,” he wrote, “hold the motor assembly to the pump base. When trying to dismantle the pump to replace the diaphragm, one bolt sheared right where it entered the black plastic base.”

Miller got the other three bolts out, but noted that they were badly corroded. He said it was the second time he’s sheared bolts on PAR pumps and that “I’ve been replacing them with stainless bolts during routine rebuilds on two other PAR pumps on the boat.”

“I’ll try,” he continued, “but I’m skeptical of being able to drill and tap the plastic to effect a repair and still achieve the alignment for a watertight seal. If it works, it will be a spare pump.

“Meanwhile, $242 got me a new PAR 36900. The $40 upgrade from the 36800 to the 36900 gets you (in addition to a higher flow rate) all stainless steel hardware. The stainless bolts go for about 14¢ each. I checked and noticed that the 36800 still comes with mild steel bolts.”

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