My friend Nick and I are still debating which bolts are tougher to break free: shaft coupling bolts or the lug nuts on an old trailer. Nick argues that lug nuts spend more time underwater and are usually torqued down a whole lot tighter than a shaft coupling screw. On the opposite side, I contend that shaft coupling bolts require you to assume the yoga pose Downward Pretzel just to see the bolts. The argument will no doubt carry on for years, but this week, as I began the slow work of liberating three seized seacocks on the 50-year-old Yankee 30 Opal (formerly Bay Star) our recently acquired project boat, I was reminded that even the most stubborn bolts can often be coaxed loose with a judicious application of penetrating oil, the right tools, patience, and muscle.
Longtime readers will remember our previous encounter with Dustin Rahl, owner of a very busy mobile trailer service in Sarasota, Fla., Trailers 2 Go. While the most corroded components must often be cut free, many of the seized nuts and bolts he encounters in his work can be liberated. On our first meeting with Rahl, the axle on the trailer for our Catalina 22 test boat Jelly (now replaced by the 1983 Catalina “Lil’ Spitfire”), had cracked at the weld, so that its left wheel splayed outward at a 20-degree angle. Dustin arrived early Tuesday to remove the axle, which was rusted beyond hope, so that he could measure it and order a new one. Alas, the lug nut bolts stood in his way. He didn’t even bother to try them cold. “I’ll just give it a shot of PB Blaster,” he said. And that was that.
Since that first encounter, Rahl has provided faithful service, most recently replacing the leaf springs on the trailer, for a projected long haul up to Practical Sailor‘s new summer office in Marquette, MI near the shores of Lake Superior. He is, as they say in the industry, a stand-up guy.
We’ve tested spray petroleum products to a fare-thee-well. Some are good for loosening bolts, others for sealing electrical connections, and others for protecting against corrosion. When it comes to loosening bolts, we’ve found the PB Blaster works best. That’s not to say the others won’t work. Its just that when it comes to the really tough bolts, PB rises to the top.
But what happens if the PB isn’t enough? Carefully applied heat from a butane, MAPP-gas, or propane torch is usually the next step. After that, its time to break out the specialty tools. As contributing writer, and former boatyard manager Ralph Naranjo explained more than a decade ago—the tools required for nut and bolt extraction can range from the most basic to the esoteric.
“Like a chef with a favorite set of sauce recipes, a good mechanic needs a tried-and-proven list of tricks to help coax rusted fasteners into submission,” writes Naranjo (see “Rust Busters: Spray Solutions for Seized Fasteners and Other Metal Hardware,” PS April 2009). Naranjo’s tools range from penetrants and ingenuity to pure brute force. The following is quoted from that report:
“For sockets, a breaker bar and the learned wisdom of just the right amount of torque works much of the time. An impact screwdriver is often our go-to tool for slotted fasteners. For really stubborn fasteners, there are nut cutters, and a wide range of torque- and shock-inducing gadgets.
“One unusual but effective fastener-freeing technique involves massive thermal change that causes an abrupt material expansion or contraction. A piece of dry ice is pressed against a stubborn bolt head to shrink its dimensions. This results in the disruption of the rusty bond and more willingness for the bolt to turn.
“Less esoteric solutions include box or socket wrenches with fewer facets, which afford a tighter grip on a nut or bolt head and allow more torque without stripping the hardware. The better your ability to apply force, the more careful you must be to avoid breaking the fastener.
“Sometimes, all a bolt needs is a few good wacks to loosen the bond, but be careful! You don’t want to damage the threads. If you can only approach from the threaded end of a bolt, you can put another nut on the bolt and tap that – not too hard. Alternately, you can use a rubberized mallet, or a piece of hardwood to insulate the bolt from the hammer.
“The rusting process also degrades bolt head shape. A last ditch effort may require a pair of Vise-Grips or sockets designed to grab deformed bolt heads. For stuck, slotted-head bolts, an impact screwdriver can be a real lifesaver
“Frozen, rusted nuts present a similar problem, but there are tools that allow you to split the nut without destroying the bolt. Nut crackers use a chisel-like edge that is screw-pressed against the side of a nut. Once the tool is tightened, a machinists hammer is used to smack the tool, and its blade splits the nut.”
If seized hardware in spars is your problem, extraction and retapping or new rivets may be your only option. If you are adding or replacing hardware on your mast and boom, two relevant reports can set you on the right path. In “Anti-seize Coatings for Spars,” (PS July 2018) and “A Riveting Report: Spar Fasteners.”
As for my own project on “Opal,” the seized tapered-cone bronze seacocks eventually freed with only a little coaxing and spray. The process described in this ancient, but still perfectly valid Practical Sailor article on keeping seacocks working smoothly was very helpful.
Freeing this leaking water pump from ye ol’ Universal Diesel 5411 took a little more patience. I doused the severely corroded mounting bolts in PB Blaster and returned the next day to begin coaxing them free. Gentle tap, tapping with a peen hammer—I hoped—would break the bonds of corrosion in the threads.
As I fitted my breaker bar and a six-point socket (12-point, bi-hex, sockets are more prone to stripping) that fit snugly on the mounting bolts, I was already going through my options if the bolts were stripped during the extraction process. None of them were cheap. I started tentatively, adding a six-inch extension to the breaker bar, giving me about 18-inches of leverage on the 3/8-inch mounting bolt. When the most corroded bolt budged, I breathed an immense sigh of relief, but instead of further loosening it, I applied a little more spray, tapped some more and moved the bolt back and forth before advancing it any further. In many ways, steel engine bolts are far more forgiving than stainless steel, which can gall, creating a nearly impossible-to-break bond.
Now for the next engine project, the dreaded shaft coupling bolts. Time to break out the Allen wrenches. If you have a favorite “secret sauce” for loosening bolts that we should test, let us know in the comments section.