Outboard Engine Locks

Among the bar-type locks, we like the Islander Outboard Motor Lock for corrosion-resistance, routine theft prevention, and good looks. The Fulton lock is also good, but should be monitored for corrosion. For really robust security, go with the Stazo SmartLock.

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In the April 1 PS Advisor we discussed locks for clamp-on outboard engines. This occasioned letters from readers, which in turn prompted us to collect four store-bought locks for a closer look. The locks are the Master Lock Outboard Motor Lock, the Islander Outboard Motor Lock from Island Marine Products, the Stazo SmartLock, and the Fulton Outboard Motor Lok. 

Outboard Engine Locks

All of these locks will easily resist the casual thief, but we were interested in which were more corrosion resistant, less noisy under way, fairly priced, and hardest to overwhelm.

Master Lock Outboard Lock
This is probably the most familiar outboard lock on the market. It’s a hollow box-section of case-hardened steel (approx. 2 mm) covered in a thin coat of soft vinyl. The box section simply slides over the clamp handles (which must be in a horizontal orientation) and is secured by a key-operated Master padlock (marine brass) with a non-captive shackle (shank). The shackle, in other words, comes completely free of the lock. The lock is inserted upward into a rectangular hole in the bar, and the shackle is inserted downward through two holes and into the lock. Bar and lock together weigh 1 lb. It will lock most clamp-on outboards up to about 40-hp.

Having had many years of experience with the Master Lock, off and on, we can report that it does the basic job well, but it rattles on certain engines at certain speeds, and eventually the vinyl gives way, water finds its way to the steel, and the bar rusts. We had a letter from a reader in the May 15 issue, reporting that his Master Lock had rusted to the point that a thief was able simply to remove it from the engine, and then the engine from the boat. The lock does come, however, with a lifetime guarantee.

Assuming the Master Lock is in good shape, it’s quite resistant to thievery. It would be a tedious job to attack it with a hacksaw. You’d have to saw through the bar section, because sawing through the lock shackle would gain you nothing. In any case, the shackle is partly recessed into the bar, no doubt to ward off both saws and pry-bars. Depending on the height of the lock from the bottom of the boat, a thief might be able to get a drill under the lock and drill it out. A lockpick might also be able to defeat it, but we’d have to assume that a skilled lockpick would have better targets to aim for than small outboard engines.

Islander Outboard Motor Lock
This is a thin-walled (approx. 1.5 mm) hollow tube of high-quality stainless steel. It works the same way as the Master Lock: The tube slides over the clamp handles (aligned horizontally), and is fixed in place by a brass, key-operated ABUS padlock. This lock has a single, stainless steel, capped pin (not a U-shaped shackle) that is inserted down into the lock through a hole in the tube. The pin is held captive to the lock by a thin cable—a nice consideration.

The far end of the tube has a black plastic cap, more or less for decoration. Removing it does nothing that would compromise the lock.

We were curious to see how long it would take to defeat this lock, so we attacked it with a hacksaw. It took about three minutes of hard sawing with a relatively new blade to saw the cap off the pin, which allowed the ABUS lock to fall out the bottom. We then tried sawing through the far end of the tube with both a standard high-speed hacksaw blade and a new carbide grit rod saw. This was a much more tedious process. Not worth it, for thief or tester. 

Outboard Engine Locks

The Islander lock is the best looking of the locks, at least to us, and, along with the Stazo lock, the most resistant to corrosion. It’s likely to rattle, and can be defeated by a concerted attack on the lock pin. Nevertheless, it would be a worthy deterrent to run-of-the-mill motor-thieving punks and vandals.

All up, the Island lock weighs 1 lb. Arne Swanson of Island Marine, maker of the lock, says the Islander carries no specific warranty; the company will consider any failed locks on a case-by-case basis. Also note that the slot in the lock is 3/4″ wide. Swanson says he has heard of a couple of late-model engines whose cranks are too large to fit in that slot.

Fulton Outboard Motor Lok
This is another bar-type lock, but Fulton’s is clamp-on, not slide-through. The two halves of powder-coated hardened steel work in shoebox fashion—the top part covers the engine clamps (horizontally arranged), and the bottom part is inserted upwards into the top part. It’s secured there by an integral barrel-key chrome steel lock, which is in turn protected from the elements by a snap-over plastic cover. It’s a good arrangement, reminiscent of a turtle with head retracted, or an armadillo rolled into a ball – it doesn’t give you much access for mischief.

The end pieces of the top part are actually folded-down steel tabs, and are not spot-welded, so one would be tempted to insert a prybar there and work the tab up until the bottom piece could slide sideways. But you’d still be defeated, because the lock is engaged in the middle of the bar. Smart.

Fulton is alone among the lockmakers in providing soft foam inserts between the lock halves, to cushion the clamp handles and eliminate vibration and rattles.

It’s not invulnerable though. Even though the package says “Long-Lasting Black Powder Coat Finish Provides Years of Protection Against Rust and Corrosion,” our evaluation lock came out of the plastic wrap with three small spots of raw steel already gleaming on the lower part of the lock. In a wet, salty environment, and with the foam inserts helping to trap moisture against the metal, rust and corrosion will eventually gain a toe-hold and start their nasty business.

With that specter in mind, we still like this lock. It’s well thought-out, the least expensive of the bunch, and would be worth owning even if you had to touch it up with paint once in a while. The Fulton Lock weighs 2.5 lbs., and comes with a limited three-year warranty.

Stazo SmartLock
Now for something completely different. This Dutch-made Stazo SmartLock, for engines up to 35-40 hp., caught our eye when we were researching the aforementioned April PS Advisor. We were sent an evaluation sample by Stazo’s hardware representatives in Thomaston, ME, and were first surprised by the sheer heft of the thing. This is a serious lock. The outer shell alone is 4.5 mm of solid, milled stainless steel, and the two parts together weigh 3 lbs.

The SmartLock is fixed on one engine clamp, not both, and the clamp needs to be aligned vertically, not horizontally. The inner part of the lock is actually trapped and fastened between the clamp pad and the boat’s transom, then the outer part of the lock is slid on and secured with an integral ABUS cylinder-type lock, operated by a special key. The lock, whose mechanism is set deep within a hardened steel entry, is designed to be very hard to pick or drill out. Not being lockpicks, we can only say that the prospect of drilling looks dismal, since you’d have to drill through to the far side of the cylinder, which rests against that impregnable outer shell, in order to turn it. The cylinder mechanism itself comes with a five-year warranty, and the key numbers are registered on an ABUS key-code card, which prevents unauthorized duplication. It’s not clear to us exactly how you would present your card numbers to either Stazo in the Netherlands or ABUS in Germany. There’s no information about that in the Stazo literature, and precious little on the ABUS website (www.abus.com). So we’d be careful about losing those keys. Without them, you might have to torch through the clamp screw to get the engine off. Or maybe cut the boat off the lock. 

Outboard Engine Locks

The SmartLock comes with an O-ring set in a groove on the back plate of the inner section, to dampen rattling between the sections. The O-ring that came with our sample was broken, so we replaced it with one from our plumbing supplies.

Conclusions
For many of us, the Stazo SmartLock will be overkill, but if you live in an area where outboards are stolen regularly, this is your lock. Among the bar-type locks, the Island Marine Islander is the best-looking and most corrosion-resistant. It’s potentially noisy, but this can be defeated by stealing the foam idea from Fulton. And although the Islander might have a weak spot in its pin, it would still provide good deterrence against the casual thief and boat marauding punk.

 

Also With This Article
“Outboard Engine Locks Chart”

Contacts
• Fulton Performance Products/Cequent, 715/693-1700, www.fultonperformance.com
• Island Marine Products, 727/698-3938, www.islandmarineproducts.com
• Master Lock, 414/571-5625, www.masterlock.com
• Stazo Marine Equipment, 207/354 0914, www.stazo.nl

Darrell Nicholson
Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 50 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida. You can reach him by email at practicalsailor@belvoir.com.

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