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Sea Savvy

Engine troubles: out with the old

Engine troubles: out with the old

A few months ago in this column, I wrote about my mechanical meltdown. When we parted company in that article, it was late at night and I was stunned with the realization that my engine was totally incapacitated and beyond my help. The only thing I could think of doing was to have a couple of cold beers, eat some supper and crash.

New days solve problems, and when I rolled out of bed at first light the next morning I was determined to tackle them. I thought there was a significant crack in the engine block or head, or, if I was lucky, a blown head gasket. The only good news was that we were in central Florida on the Intracoastal Waterway, where we could find help. Often we’ve been in the BahamasOutIslands or other remote areas where there was no help when things went wrong.

The possibility loomed that the best solution might be to get a new engine rather than repair my 20-plus-year-old Perkins T6-354. You can rebuild almost any engine — and particularly this one, which had been running exceptionally well. But parts were getting more and more expensive for this engine, and it consumed much of the engine room, making a rebuild very hard to do in place. So I needed someone who could help with a correct diagnosis, make the necessary repairs, or, if necessary, install a new engine.

And although things like this don’t happen quickly, I needed it all quickly. Many people boat solely for pleasure, but we must meet many destination and project deadlines associated with our writing. Mechanics often say they can’t get to you for several weeks, especially if you’re not a regular customer. And mechanics who don’t do the type of job you need on a regular basis will often take longer in the process.

Research for rescue

I was on the cell phone as soon as I thought people might be awake. Not only was I uncertain about what my engine needed, I knew nothing about who could do what, when and where. And I was stranded, on the hook, out in the Indian River. In the earlier BC (Before Cellular) days, research would have been extremely difficult because I would have to have arranged a tow to a marina, where I could access a land line, stand in a phone booth for hours, not be able to get return calls, and then find out that I should have been towed somewhere else in the first place. I knew we had to get a tow, but to where?

I first called TowBoatU.S. to find the radius available with my “unlimited” towing. It was enough to cover a lot of possibilities. I then started calling friends in and around the area to find a good yard and mechanic. I learned of Eau Gallie Boatworks, a small but popular yard very close to our disaster scene. I talked with Capt. Kevin Miller of Absolute Marine Towing & Salvage, the TowBoatU.S. operator for the area, and he was very helpful, mentioning several possible shops, including Marine Pro — around a 20-minute drive from the yard. I called all the marine engine repair shops that he and other people had mentioned. They were all too busy and some seemed, in my opinion, unable or unwilling to discuss the problem thoroughly with me on the phone. I also called my old friend Tino Mastry of Mastry Marine in St. Petersburg — across the Florida peninsula — which had sold me (through Gulfstar) a 6-354 Perkins in 1979, when we were all a bit younger. Mastry Marine is one of the major diesel and diesel products companies in the country, and it’s a huge Yanmar distributor. I’d heard many good reports about Yanmars, and Mastry and knew this engine would be a front-runner if I had to get a replacement.

Tino has so many good friends that the joke around his company is they won’t let him sell diesels — probably a wise move from a business perspective. But he gave me good advice and confirmed my choice of whom to call in the area in which I was located. It was Marine Pro, the same shop on the list given me by the TowBoatU.S. operator and recommended by several others. I discussed my problems and symptoms with Marine Pro owner Frank Monachello. He took the time to talk extensively about the situation.

I’ve owned boats for more than 54 years, and I’ve owned diesels since the early 1970s. I’ve done almost all of the repair work on them, as well as many gasoline engines. When I talk to a repair facility on the phone, I usually get a pretty good idea of whether they know their business and are giving me the straight scoop. I felt good about Monachello.

He and several independent Perkins experts with whom I talked that morning gave me an ugly picture — one I hadn’t expected. The huge chunk of aluminum on the starboard side of the engine — which housed the header tank, the heat exchanger, the freshwater-cooled exhaust manifold and the intake manifold — had been susceptible to failure over the years, possibly because of a casting defect. A breach sometimes occurred, allowing fresh cooling water to flow into the exhaust and onto the pistons. One dealer told me he had boxes of these defective parts. Clearly, this was a possible cause of the symptoms. The part alone cost more than $8,000. It was looking more like I might want to get a new engine, so the issue of the tow destination and repair shop was even more critical.

The autopsy

I chose to go to Eau Gallie Boatworks, about a mile from where we lay anchored. I had talked with the owner, Finnbarr Murphy, and liked what I heard. “I know you have some diesel specialists coming, but if you need us for anything, we’re ready to do whatever you need, whenever you need it,” said Murphy. “We can make it work for you.” There was no equivocation, no “well, maybes,” and I’d heard some very good things about this yard. We saw this demonstrated on a daily basis during our experience there. But from our phone conversations, I saw one possible problem: I would have to learn to understand “Irish” speak, and Finnbarr would have to learn to understand “Southern” speak.

Mark Eiler, vice president and service manager of Marine Pro, arrived that afternoon and dove in. Not only did he seem to know what to do, he worked quickly. This proved to be true of the rest of the Marine Pro crew. Eiler first asked a lot of questions to find out what had happened. Then he pressure-tested the header tank — with a tool designed for this purpose — and, as expected, it was leaking. He then loosened the exhaust riser. Fresh water and antifreeze flowed out. This had to have been caused by a leaking manifold, a cracked block or head, or a blown head gasket. He pulled the manifold and the head; the head gasket unfortunately was perfectly intact. But water had gotten into the forward cylinder, and there were signs that smaller amounts had entered before. Our best guess was that a small breach had existed for a while and that it had finally opened wide the day of the failure. Fresh cooling water had run into the exhaust from the manifold. When Eiler poured water into the header tank to test the theory, it immediately ran out the forward exhaust port. The coroner’s report was in: The curse of the aluminum hunk had killed my engine.

Replacing the part didn’t make sense to me. I could have had it fabricated or gotten “make do” replacements that are available because of the many Perkins engines in tractors and trucks, as well as boats. The engine still had good compression, had been starting instantly, and was running well until that day. But we travel 3,000 to 5,000 miles a year in Chez Nous, much of it in out-of-the-way areas — such as offshore or in the Bahamas — where we can’t readily get help for major breakdowns. Reliability isn’t a luxury for us; it’s a necessity. Based upon our usage as well as all the other facts, the decision was as obvious as it was painful: Get a new engine.

I chose Yanmar because of its reputation, because I’ve known so many owners who love them, and because I could get more horsepower with less weight, noise and vibration. To replace the 160-hp Perkins I went with a 200-hp 4LHA-DTP. The rpm would be higher, and I’ve always been a believer in slow-turning diesels, but its smaller size would make it easier to work in the engine room. This is of critical importance because I do about 98 percent of my own repairs, many at sea or at anchor. Also, the smaller size would make it easier to install than another Perkins or similar-size and weight diesel.

As a further clincher, Monachello told me I could use a Borg Warner transmission with the same footprint as the Perkins. This would mean that the stringers wouldn’t have to be modified — a potentially time-consuming and costly job, even though Marine Pro had aluminum stringers for various applications ready to go. Yet another plus was that Mastry had engines in stock, even though it was shipping millions of dollars worth of power plants to major boatbuilders.

Out with the old

With no hatch over the engine room, both the old and new engine would have to be taken through the engine room door (around 22 inches wide), down a narrow passageway, and then up (or down) the companionway. Cutting a hatch through the center cockpit would have been expensive and time-consuming because of wiring, plumbing and insulation. Also, we would have to have moved into a motel room (more money), and the boat is our home and office.

The dismembering began. The Perkins was stripped to the bare block in about a day primarily by Eiler and Collin King, working together like a well-oiled machine. Removing parts like the starter, multicooler and fuel pump was easy enough. As the parts were removed they were carefully “preserved” so that they could be reinstalled or reused. I found myself lingering over each piece, as I had labored over each at one time or another (some, many times) during the years.

I also found that it was important to save some valuable things that might be considered “junk” and that otherwise would have been discarded in the effort to get the job done as efficiently as possible. Items that I saved included many of those expensive Awab hose clamps, fiberglass hose couplers, hose and recently installed wiring.

The transmission was more of a problem. The aft mounting feet of the engine were attached to that component, so the crew brought aboard an adjustable pipe A-frame with a chain hoist. After properly sizing and placing the A-frame, it was easy to lift and prop up the block so that the transmission could be removed and carried out. It was also easy to remove the feet extending out from the front of the block. Next came the bell housing and flywheel. With each component removed, the engine became not only smaller but much lighter. Trimmed to the bones, it was ready to move. But we couldn’t fit any elephants down the hatch to pull it. No problem.

Eiler and King laid a pathway of boards from the engine room to the base of the companionway. (I had removed the stairs.) They opened a big container of GOJO and smeared the soap along the planks. With a lot of muscle and judicious use of the A-frame and chain hoist, they positioned the stripped block on the slippery road and slid it to the companionway. At that point, Chez Nous’ sailing rig really paid off. We used the boom as a crane. Monachello had crafted aluminum Ls to fit over the track on the boom to prevent damage. And he’d crafted starboard insulation to keep the Ls from scarring the boom. With carpet around the spar to cushion the chain of the chain hoist, all was ready. Monachello left nothing to chance. He lifted the block about a quarter-inch to test the strain on our rig. There was slight deflection on the boom, so we added an extra halyard near the point where the chain hoist was attached to the boom.

With two people guiding the block from below deck (not from underneath) and three on deck, it rose easily through the companionway, after being tilted and turned to fit the space. Several dozen people were watching, all expecting the Chez Nous to heel far over as we swung the engine out over the dock. Tough, heavy, old lady that she is, she hardly moved an inch, and we lowered the block to a cart that was rolled ashore and up onto a trailer. I couldn’t believe it. In such a short time, that huge chunk of metal that had taken us so many miles and over which I’d labored, bled, cursed and prayed for so long was gone. (But now it’s for sale through Marine Pro — — or you can contact me.)

A touch of magic

When repowering a boat with a different engine, you don’t just buy one and put it in. Someone has to do a lot of figuring. It’s an area of expertise that’s very different from those of mechanically removing and installing, but without it a great installation may be, nevertheless, deficient. While I was figuring how the heck I was going to pay for it, Monachello and the experts at Mastry Marine were figuring how to trick it out.

The effect of an engine on a boat involves much more than its horsepower. It involves the reduction in the transmission. Too much or too little can make the engine overwork or waste its energy. It also involves the size and pitch of the prop.

“Understanding pitch,” explained Monachello, “is like imagining the propeller and boat in Jell-O, and there is no slippage. If you have 22 inches of pitch, the boat will, in theory, be pushed forward 22 inches through the Jell-O with one turn of the propeller.”

Too little pitch will make the propeller spin too easily and allow the engine to over-rev without getting maximum benefit from its energy. Too much pitch can cause the engine to work too hard. And the size of the propeller also comes into play. The wider the distance from tip of blade to tip of blade, the more thrust. However, the outside tips of the blades shouldn’t be too close to the hull. And the combined effect of size and pitch must be right for the engine, transmission and boat.

The combined effect of size and pitch also is heavily influenced by the weight of the boat, which changes with loading. We carry 330 gallons of diesel and 300 gallons of water. Using the very rough formula of 8 pounds per gallon, that’s a difference of approximately 5,040 pounds between full and empty. Then add to that food and other stores for being at sea six months at a time. But wait, there’s more. The shape and length of the hull also comes into play, not merely as to hull speed related to boat length but also as to drag caused by configuration — in our case, the full keel and rounded underbody of a motorsailer. And then one has to be sure that the prop isn’t exceeding the load capacity of the shaft and strut.

Monachello got to work. There are computer models to help with this, and he used them — but he also used his gray matter. I listened on my end of our cell phone conversation as he played the numbers in his computer and talked about what would work, what would work better, and what would be bad. As I listened, I realized that I could throw all the money in the world at a new engine but wouldn’t be getting its worth without someone like Monachello to do the right kind of magic to achieve the right balance between components. This only comes from years of experience.

Where the sun never shines

While the components were being gathered, I tackled that mysterious hole where the sun never shines: the bilge under the engine. It was bare to the world. I timidly looked in, wondering what secret horrors I’d find. Actually, once I got rid of the years of accumulated, baked-on grease and slime it didn’t look too bad. This involved grease-cutting cleaners such as Super Orange cleaner/degreaser by Star brite, a steam cleaner, and many hours of old-fashioned hard work.

I found that you have to accept that, unless you go nuclear with the project, an old bilge isn’t going to come sparkling clean. However, that didn’t bother me, because I knew I’d soon be doing something stupid to make it dirty again. We painted it using Interlux’s Bilgekote, a paint formulated for the purpose. I found the paint to work well, and it looked great. It is critical during this process to use a good respirator suited for the material that you’re working with. This is worth every bit of the money it costs.

To “do the job right” you paint the entire engine room when you repower. But we’ve found over the years that when you live aboard full time, you can seldom “do the job right,” according to yachtie standards. Such was the case with this job. The fumes from the paint bothered us, even though the boat was well-ventilated. We could have moved to a motel, but we were having enough trouble finding the money to pay for the engine. So we only painted the area that we would be unable to access when the new engine was installed. We saved the rest of the job for a time when we could temporarily move off.

With the engine out, you can do all sorts of other jobs you’ve been putting off because of access problems. For example, I lengthened the hose for an air conditioning condensation drain so that the water would go directly to the sump. I fixed one of the three bilge pump hoses that had become slightly crimped over the years. I cleaned out drain holes to allow water to run from one sump to another. I got rid of an old engine-driven refrigeration compressor and its components.

This repower also presented another opportunity. I installed an X-Change-R (model 946D). This allows you to pump out your old oil from up to three engines with just the flick of a valve and a switch. (Other models give more options.) You can also fill each engine the same way. But it’s best to plumb the drain hose from the bottom of the engine oil pan, and when the engine is in place — at least on my boat — it’s difficult to do this. We did it while the engine was in the shop so that it was easy to complete the hookup when the engine was in the boat.

In with the new

Marine Pro sent in its repower team for this phase. Bret Parker, the repower manager and treasurer, swung into action with his crew. The action ranged from meticulous planning and wiring to heavy moving. Even though the Yanmar is smaller than the old Perkins, it still required some trimming down to get it to the engine room. Various components were removed, with care taken to not remove sections of the water and lubrication system unless really necessary. The engine and transmission were lowered down the companionway with our boom again, but this time sections of StarBoard were screwed to the boards to slide the engine along.

The StarBoard worked well. Getting the engine through the engine room door required some careful twisting and turning, but it was quickly done. As with other parts of the project, this job was permeated with a, “We can do it and we will do it” attitude, rather than the, “Duh, well, I dunno … lemme scratch and think about it for a while” attitude we often see with people who don’t do the particular job regularly.

While the new engine fit the old stringers, we discovered that the oil pressure sending unit, a portion of the transmission fluid line and the oil filter would jam into them. A grinder made short work of this issue. The stringers are very thick solid fiberglass, and cavities were easily carved out to give clearance. The Yanmar is not as long as the Perkins, which left a lot of space in front that served perfectly to fit an Aqualift muffler so that it would be out of the way. This bonus space also allows easy access to components at the front end.

This made the job of replacing the standard alternator with a Balmar heavy duty unit particularly easy. We have exceptionally heavy duty battery banks of two Surrette 8D modular batteries with Hydrocaps and two Surrette 4D modulars. They do a great job of keeping our equipment — including an icemaker, entertainment center, computers and two inverters — going all night without generator use. We like to charge them with the engine during the day’s run without having to use the generator. To do this, we installed the Balmar and an ARS-5-H external voltage regulator.

The regulator enables us to tailor the alternator to do just what we need as to battery size and type. (You can set it to work with many other types of batteries.) It also can sense the temperature of the alternator and battery bank, which helps avoid damage to either. Another particularly useful feature is that you can adjust its output to match the size drive belt used. Heavy duty alternators create extra loading on belts. Belt overloading can cause problems such as overheating the alternator and rapidly deteriorating the belt. Adding a second belt means getting another engine pulley wheel and another alternator pulley, which takes space and money. But this alternator, with the appropriate setting on the voltage regulator, works well with one belt, particularly the Dayco Top Cog. The alternator with our setting is rated to put out a maximum of 110 amps. In theory it would put out more, but that would require two belts. Besides, we simply don’t need more and prefer to not load this or any other equipment to the max.

The Yanmar came with an impressive but large control panel that wouldn’t fit our steering pedestal without essentially reinventing the wheel. So we swapped it out and had Marine Pro install VDO gauges in the existing pedestal panel, connecting them with the Yanmar wiring harness. This meant that they had to do a bit of brain surgery in the pedestal, but it saved a lot of space and rearranging of other components at the steering station.

If we’d kept the old propeller, we would have lost much of the benefit (read: power and speed) of the new engine. A diver pulled it and installed a new Michigan 23 L19 to replace the old smaller, flatter prop.

Suddenly — and, it seemed, miraculously — Parker was saying, “OK, let’s start ’er up.” This was the moment for which Mel and I had been praying for almost three weeks. The engine already had been run and tested at Marine Pro, which has a dynamometer so that engines can be tested under load before installation. This also is done at Mastry. This is expensive equipment but an invaluable capability. As Mel and I held our breath, Parker calmly said, “When you push the button it’s going to start right away. If it doesn’t, something’s wrong.” It did.

Free at last

Then came the sea trial. For Mel and me, “nervous” and “excited” would hardly begin to describe it. For Parker, it was a matter of close attention and many checks. When I put her in reverse to back away from the slip I couldn’t believe the additional power and control. When we got her out to open water, we began to open her up. Chez Nous behaved like a thoroughbred stallion just let out for a run. Mel and I were ecstatic. Parker, however, shook his head.

“She shouldn’t be turning that fast, and she’s a little cool,” he said. “I think you need another inch of pitch on the prop.”

I’m thinking, Good gosh, I just paid a fortune for the prop that’s on here, when Bret cut in. “It’s really hard to always get the pitch just perfect,” he said. “So when we do a job we’ll give you one free repitch if it needs it. I know you have to get moving, so run her on down to Fort Lauderdale, see how she does, and give us a call.”

We got to Fort Lauderdale in record time and reported in with Marine Pro, answering Monachello’s questions. He was clear: We need another inch of pitch.

We sent the prop back, and it returned a few days later with 20 inches of pitch. The rpm dropped from 3,600 to just over 3,400, and performance was much better, as to speed and power per rpm. This is with a slick hull. Add the inevitable drag from typical marine growth, and we’ll still have plenty of power. The Perkins had barely been able to push the boat at 7 knots at its cruising rpm of around 2,200. A little chop or wind on the bow would slow us considerably. The Yanmar, at a cruising rpm of 2,600, had us moving at 8 knots and largely unaffected by moderate a head sea and wind. At 2,800 rpm, still a comfortable cruising level, we were making 8.5 knots. At wide open 3,400-plus rpm we hit 10 and held.


A 50-hour checkup was required not only for warranty purposes but because it makes good sense. This included adjustments to things that would normally settle, shift or change with the shock and stresses of the new life of a new engine. We took the boat back to Marine Pro for this.

The list included adjusting valve clearances; inspecting the turbo cooler; checking liquid seals for leaks; looking for chafing of wires, hose and cable; and, very importantly, an alignment check. When you set an engine on new mounts, its weight, torque and thrust will make it settle the rubber part of the mounts. As I had suspected (from an excessively leaking stuffing box and vibration), a realignment was needed. A poorly aligned engine not only can cause vibration and shaft seal leaking but can also be harmful to the transmission.


Since the repower, we’ve taken Chez Nous back up to the Chesapeake Bay area, some offshore, some inside. We’ve made this trip many times. The extra speed and power meant far more than just covering more miles in a day, which was great in and of itself. It meant that we could reach a safe harbor easily when a 60-plus-knot storm formed offshore. It meant that we could reach timed bridges on schedule, while before we’d have to wait an extra hour or more because we’d “just missed it.” It meant we didn’t have to change planned destinations because a head wind came up. And it meant that a guy on a 140-foot megayacht yelled at us for throwing him too much wake. I like my new engine.

Tom Neale is technical editor for Soundings and lives aboard a Gulfstar 53 motorsailer. You can buy his book, “All in the Same Boat,” at