Repowering a Great Old Boat

by Ellen Landrum and John Broussard
originally published in Living Aboard magazine

Nearly eighteen months after purchasing a new Yanmar 3GM for our Alberg 30, Rubicon, the installation--a saga that has deeply influenced our lives for more than a year--is coming to an end. The engine is in. We saved the better part of seven thousand dollars by doing it ourselves, and managed to familiarize ourselves with an endless array of installation techniques, the newest in shaft and coupling technology, the best fuel and steering systems, and the ultimate propeller (all relative to our boat, of course). Every choice we made in terms of equipment and technique was carefully researched and well-pondered. Even with a relatively small budget, we feel that we’ve put together a modern, but manageable engine system, bringing our old girl from 1965 to 2005 technology.

Choosing the actual engine was a no-brainer. We wanted a new, reliable diesel. We plan to sail far from home and wanted a world-wide name. Finding parts and mechanics abroad would be easier with an international distributor. There have been many successful installations of Yanmar 2GMs in Alberg 30s. After much debate, we decided to go with Yanmar’s 3GM model, giving us one more cylinder and twenty-seven horsepower, versus the 2GM’s eighteen. The price was higher and the engine itself a bit bigger, causing some concern, but we plan to do extensive cruising and a great deal of motoring. The extra horsepower will allow us to run the engine at lower RPMs, reducing wear and tear over a long period of time. We can also push a three-blade propeller, which will be handy fighting a current or chop.

1. Engine compartment, empty. Shaft is visible with string run though to establish centerline. Hoses are bilge pump and cockpit drains. Boards on either side of shaft are there to support engine jig as measurements are made for new beds below. New beds will be built where green outline is visible on the hull.

Rubi was splashed this past spring and we moved aboard, using our 3GM as an elegant coffee table. Yanmar’s Marine Engine Installation Manual proved invaluable for its schematics and simple instructions. We found details of the installation process—making an engine jig, finding the centerline of the shaft, aligning the jig and from that alignment, building new engine beds—in numerous books as well as on numerous boatowner’s websites. Troubleshooting comes easy with a 56K modem.

Our first real obstacle came when we discovered that our jig, with the factory mounts, could not go back into the engine compartment far enough or low enough to meet the shaft and correctly line up with the centerline. The Alberg 30’s beautiful lines and sailing performance are made possible by long overhangs and a narrow hull which rises quickly as it goes aft. We ended up going with a smaller engine mount provided by PYI Inc., a good 2 inches shorter than the Yanmar factory mounts. Not nearly as much rubber as the Yanmar set, but we were reassured by Oldport Marine, our Yanmar dealer, that they’ve worked well in the past.

2. New beds, solid oak, temporarily attached to hull with Bond-O.

We temporarily secured the engine jig, with new mounts, in the engine compartment in order to take measurements for the size of the beds. The beds themselves ended up being over 10 inches tall at the forward end, in order to accommodate the angle of the transmission/shaft coupling. Bond-O, from the local auto parts store, allowed us to move the beds in and out of position easily as we shaped them with a reciprocating saw and belt sander. Much carving and planing later, we felt good about the jig’s position in the engine room. It was slightly lower than the center of the shaft. The fiberglass on top of the beds, and the room for adjustment in the mounts would more than account for this height difference.

3. Fiberglassing new beds—heaviest fiberglassing done where bed meets hull.

Compared to the shaping and placement of the beds, fiberglassing them in pace proved easy. We decided to go with 1 layer of fiberglass mat, doused in West Systems epoxy and hardener. The mat pieces were basically folded in half and the fold laid along the edge of the bed where it met the hull. All pieces, all layers, were done this way and increased in size to eventually cover the wooden beds. We covered the mat with fiberglass roving, a nightmare to manipulate but very strong. Then came a second layer of mat, a second of roving, and then a final wrapping of the beds in fiberglass cloth.

Rubi was hauled on July 14, 2004 and the old shaft immediately pulled to get the dimensions for the new shaft. 27 and three-quarter inches was settled on, including the space needed for the couplings. Our beds were almost correct--a bit far to starboard, which has something to do with an off-center stern tube. Perfect height, though! Having dealt with this issue, we can say with authority, never assume the sterntube and shaft are at the centerline of the boat. Our sterntube is slightly to starboard and we ended up widening the port engine bed and shifting the entire engine to starboard to get good alignment. And yes, alignment is the most important step in the process, but there are a thousand ways to adjust, tweak, and correct the alignment once the engine is in place. Had we had the opportunity to pull the shaft during a winter haul, get the measurements, and run a string through the sterntube to for alignment, much of this drama would have been avoided. But hindsight is hindsight and we were happy to have made it this far.

4. View of engine transmission and engine coupling, flexible/drivesaver coupling, shaft coupling, and shaft-seal system. Hose leading off shaft seal is for lubrication of the shaft. Shaftseal allows water to continually enter the system--hose leads to waterline and water remains in hose, instead of bilge as in traditional systems. Black hoses are bilge pumps. New seacocks are for cockpit drains.

Rubi went back in the water the third week of July with a new shaft, coupling(s), new prop (a three-blade Campbell Sailor) and zinc. Our measurements for the shaft proved accurate and New England Propeller, based in Plymouth, Massachusetts, did a fine job machining a beautiful new piece of steel (Aquamet 22 Stainless), complete with keys and coupling. Our new PSS shaftseal, which we discovered at the Miami Boat Show, worked perfectly, not a drop in the bilge. Essentially the shaftseal uses bellows and finely milled stainless steel under pressure to seal shaft at coupling, eliminating the need for packing gland. A PSS flexible coupling, or “Drive-Saver,” was fitted where the engine and shaft couplings meet, reducing vibration and acting as a sacrificial piece should the prop and shaft find themselves in harm’s way. We wrapped the beds in fiberglass cloth for a final seal, and painted with Interlux BilgeKote. After the paint dried, John proceeded to drill for the mounts. We used the biggest lag bolts we could find to attach our newly named “Chug” to her final resting place (let’s hope). With the flexible coupling tightened up, she was ready to spin.

5. Engine installed! Beds are sealed and painted with a notch cut for seawater inlet at lower left. Expansion/cooling tank mounted to upper right. Front mounts are visible, wiring loosely run.

The final chapter included the incidentals--all of the systems needed to fuel, start, and run the engine. John began with the fuel system. Both tank and Racor filter were installed in the cockpit locker and fuel lines run to engine and back. Simple. The hardest part came in fitting an average-sized man into an engine compartment that barely accommodates its engine. Yanmar’s gauge panel was installed in the cockpit, despite their warnings that it should not get wet. What? Asking that something stay dry in a sailboat is like asking the sun not to set. It just can’t happen. We recently covered the panel with a Plexi-glass box, which keeps her relatively protected. Yanmar’s wiring harness, which came with the engine, was simple to install and with a few battery cables from a local auto-parts store, we had electrical power.

We purchased a Vetus single-arm control (combination throttle and transmission) after reading about a similar repowering done on a similar boat, Glissando, a Pearson Triton based in Maine. Like us, the owner had a dual control left from his previous engine and attempted to use it with his new Yanmar 2GM. As it turns out the engine’s governor is simply not compatible with dual controls, designed for gasoline engines. The throttle tends to creep back when in gear. We installed Teleflex 33C-series cables from the controls, mounted in the cockpit, to the engine, which went in easily and are working beautifully. As for the Vetus decision, we could not be more pleased with our choice—easy to operate, reliable, adjustable and smart looking.

6. Rubicon under power for first time in over 2 years, transiting McArdle Bridge in Boston Harbor.

At the end of it all was the exhaust system. We spent three or four days anxiously awaiting the arrival of our last few parts, all special order. For the exhaust system, we installed nearly 10 feet of 2-inch exhaust hose, a Vetus Waterlock muffler and a Vetus air vent, or anti-siphon valve, and a brand new 2-inch thru-hull. Literally all of it arrived one Saturday evening and John set out on a quest to have the engine started by midnight. Squeezed into the stern lazarette he drilled for the thru-hull and installed the hose, spliced the muffler into the system, installed the air vent and we were nearly there. Eight hose-clamps and a gallon of antifreeze later, we turned the key to much rumbling, coughing, and eventually the incredible sound of our Chug running for the first time since the factory. She struggled and puttered but eased into a nice idle. It was nearly midnight, and for us, the culmination of the largest test of our do-it-yourself, mechanical capabilities to date. A project of endless complications, endless decision-making, endless painful squeezes into small spaces. But the next evening, as we pulled out of our slip at sunset, we had a new boat. Boston Harbor saw us beaming with pride, giggling as we toasted to Chug, and to our hard work. It is a pleasure for any boater to turn the key and start the engine, but we cannot think of any greater pleasure than turning the key and starting an engine that you know as well as we know ours.

As for advice, patience is the key to it all. We waited for parts, waited for epoxy to cure; we found missing plugs and strange metric hose sizes and tasks that might have taken hours took days and four trips to the store. There is nothing involved in repowering that a pair of reasonably intelligent folks can’t handle. The challenge is managing the multitude of tasks, sticking with it and securing all of the endless hoses and barbs and cables and couplings. It is a comprehensive learning experience and one we would not trade for the money and time-savings of a professional installation. It was time-consuming, arduous, and at times overwhelming, and as Mark Twain said so well, “I'm glad I did it, partly because it was worth it, but mostly because I shall never have to do it again.” Or so we hope.

Ellen Landrum and John Broussard took their Alberg 30, Rubicon, on her first extended cruise from Boston to the Florida Keys in 2004. 2005 is their boat’s fortieth year, making her older than either of them! A professional captain and freelance writer by trade, they hope to continue cruising well into the future, with their infant daughter, Sophie, on board.


Our Yanmar and its systems were put to the ultimate test over the past three months as we’ve logged nearly 1800 miles from Boston to Miami, ninety-percent under power, via the Intracoastal Waterway. The engine has performed like a dream. We’ve met several boats with engine troubles, setting them back in confidence and marina fees. Every time we encounter these folks stuck at the dock, we look at each other, glance at the gauge panel and grin thankfully. The only changes we’ve made have been a new Balmar “smart” alternator and an accompanying bank of AGM batteries. In the future we may consider re-pitching the propellor, just to have the engine work a bit harder. We’ve soundproofed the engine room and found that even after a ten-hour day of motoring, there is little noticeable heat coming from the engine room. We’ll keep her, I suppose!


Yanmar: www.yanmar.com
Engine, gauge panel, wiring harness, transmission coupling, installation manual.
Oldport Marine: 401-847-9109 www.oldportmarine.com
Yanmar dealer, offered very constructive advice and excellent customer service; an all-around pleasure to work with. Based in Newport, RI .
Boulter Marine Plywood: 617-666-1340 www.boulterplywood.com
Supplied oak for the beds. Somerville, MA
Vetus www.vetus.nl
Waterlock muffler, single arm control, air vent.
PYI: 1-800-523-7758 www.pyiinc.com
Drive saver, PSS shaft seal, engine mounts
Tempo: 1-800-321-6301 www.tempoproducts.com
Fuel tank, endless array of fittings, strap-down kit.
West by North: www.westbynorth.com
“Campbell Sailor” propeller, based in British Columbia, CA
New England Propeller: 1-800-635-9504 www.neprop.com
Shaft, coupling, prop spacer.
Hamilton Marine: 1-800-639-2715 www.hamiltonmarine.com
Exhaust thru-hull (2’’), exhaust wrap; invaluable resource for hard-to-find parts, cheaper than the big guy.
Go 2 Marine: 1-877-780-5670 www.go2marine.com
Engine specialists on hand, great selection at great prices, quick shipping.
West Marine: 1-800-BOATING www.westmarine.com
Irreplaceable for last-minute epoxy needs, hoses, barbs, clamps, etc.

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