Now that we have finished the full repower of the diesel engine on Nymeria, it is probably time for a complete update. The process was significantly more difficult than we had planned. It took nearly a year from the decision to proceed, to the day we left the work dock under our own power. There were several issues during the installation that had to be worked through. Worst of all, it cost over twice what we had thought.
So, why would we go through this? Everyone is going to have different levels of tolerance, and financial needs, but I’ll try my best to describe our reasoning. When we first got Nymeria, the survey had stated that the existing Westerbeke engine was original, but it showed clear signs of removal and refurbishment, probably around 2011. This was a big selling point for us as we want a reliable engine. The hour meter read just over 600, a baby in terms of hours, but we had no way of knowing how accurate this was. Was it reset when the refurbishment happened? There is very little chance this 35+ year old engine only has 600 hours. This was the first major reasoning. The unknowns. Signs that the engine is old were clear, and many parts had clearly been replaced as they were not original, nor OEM Westerbeke parts. Several parts in the cooling system seemed to be custom and “hacked” together.
The engine ran generally well, but we started seeing issues that would show its age. Mainly its struggles to start. It would take several seconds on the pre-heat, and several seconds on the starter to get her to fire up. Often we would have to add throttle to keep it from dying right away when it was cold. The long start is sometimes a sign of poor compression in the cylinders. A few months into our running it. We had a failed main belt. This stopped the main coolant pump and the engine overheated. Me being not so smart, decided to try and make it back to the dock limping at idle. Well, this overheated the engine enough for it to shut itself down. While fixing these issues, we discovered that there was never a thermostat installed, and several bypass lines in the coolant system were closed, or simply removed. More clear signs of cooling issues in the past. The final straw was on our way home from the Harvest Moon Regatta one of the “custom” coolant hoses failed. We spent over a month trying to find/build a replacement. Because of the old engine, and the hacked system, none of the parts were standard sizes. Our choice was to either replace the whole coolant system with the OEM Westerbeke parts or find another hack solution. The OEM parts would have taken months to manufacture at significant cost and significant and unknown rework of other hacks to allow the OEM to install correctly. In the end, we hacked an old piece of stainless steel from an old bimini into the only 4 ft of hose the right size in the area (non-standard size, of course).
We had had enough, so in November we started looking into a full repower. First issue, find a mechanic/company willing to do the work. We called every diesel company in the Kemah/Galveston area. The ones that actually called back? “It’s not worth our time for such a small job, call company X”. We had already called X a few times, but nobody ever called back. We finally had one company have us sign an agreement saying they would at least come out to the boat and have a look/start an estimate, but we were ghosted as soon as we signed the documents. Finally, Brent, our electrician turned good local friend, made a call for us. Within the hour, we had an appointment for someone to come out and give us an estimate. Judson from Mockingbird Marine arrived on the boat soon after and started having a look. We immediately enjoyed him, and he seemed excited about the work. We chatted about requirements, wants, issues, and our future plans. He had worked with Beta engines a few times and thought it could be a straight drop in replacement. Because we have a newly installed bank of Lithium batteries we needed to design a custom charging system as Lithium batteries can melt a standard alternator if left unchecked. A few days later we get a full speck and initial estimate:
New Beta 25 engine including high output 120 Amp alternator, DC -> DC charging to charge the house bank of Lithium batteries as well as the standard AGM starting battery from the alternator, and a new BMS to isolate the Lithium bank in case of issues. All in ~$15k.
In our heads, Shannon and I had long thought $20-25k for a full repower so it didn’t take us long to say go, and put down a deposit. This is where the troubles began. When they finally went to order the engine, due to, you know, everything, there wasn’t one in stock, and the price had increased significantly. The wait time was at least 4 months. Well, we’ve already started, let’s just get on the list and hope.
Weeks go by with not much new information. Occasional updates with “still waiting to hear from Beta” but not a whole lot else. Finally, after we had decided to move to Galveston, we got notification that the block had been manufactured in Japan, and was on its way to Beta in England to be built. Things were moving. Judson started doing more detailed planning, and had a “final” new estimate ready that should contain everything.
~$22k and 2 weeks of work. Still within our original estimates, and actually happening! June comes along and the engine is on its way to Kemah. We started planning the time “on the hard” and getting a place to stay lined up.
The day arrives and we fire up the old “beke” one last time… She doesnt start. It took a few more attempts, but she eventually fired up and we made the 6 hour trip to the work dock at Seabrook Shipyard. The process begins fairly uneventfully. Old engine comes apart without much issue, and is removed. Once we lower the new engine in, we quickly determine it is not just a “drop in”. There are minor differences in the mounting brackets. With everything as is, we won’t be able to perfectly align the engine with the prop shaft. Seems the old engine had a flexible coupler to account for this. Judson is not a fan of those couplers so first major modifications and custom parts get created. A few days of work later. Engine block is mounted and properly aligned with good adjustability in all directions.
The next major issue is the exhaust. On the old Westerbeke, the exhaust outlet was reversible, so due to the engine being “backwards” due to our v-drive transmission the exhaust still ran from the “aft” of the engine. Well, the Beta is not reversible so we had to design a custom exhaust that would route the dry hot exhaust back to the water injection elbow. All without interfering with the companionway stairs, or making the service of the engine difficult. In the end Judson designed a solid dry exhaust system and got it all mounted. But that was another few days of work. We’re now over a week behind the original 2 week estimate.
Wth a complete exhaust, fuel system, and raw water system installed. It’s finally time for the first startup. I insert the key, push the button, hear a *click*, then nothing. Ha, it was user error, this engine starts with the key, I had pushed the “stop” button. Second try, turn the key, and she immediately fires up and runs happily!
Next issue, advanced charging of Lithium batteries. This is a fairly new field as safe Lithium Iron Phosphate batteries have just recently become reasonable for marine applications. With no protections, these batteries can easily pull enough amperage to overheat, and melt even a high powered alternator. We have several protections. We’ve installed a Victron Smart BMS 12/200 designed to limit current from the alternator. We have also isolated the charge path such that instead of chagrin directly from the alternator, we are charging from the start battery via 2 30 amp DC/DC chargers. This should limit our charge current to 60 amps. This plus the 10-15 amp loads needed for house loads and engine, should be well below the output of the 120 amp alternator. Our first test of a single 30 a charger goes well, but once we turn on the second, the alternator begins to overheat. We measured just over 80 amps output, but the alternator still is running well over 250 degrees. Days of debugging later we determined the alternator just can’t seem to handle its rated load. Beta agrees to warranty replace it and sends us a new 120 amp alternator. First test, same issue. It overheats at 80 amps. Days more of troubleshooting, and we give up and order a known good, Balmar 120 amp alternator and Balmar regulator. Once installed, we throw the full 80 amps at it and it barely flinches. Problem solved, but weeks wasted, and an extra $1000 worth of parts.
It’s finally time for some sea trials. Beta says the new engine should run all day at 3600 RPM at not too far about 180 degrees. On our first sea trial we discovered the first issue. The display panel that comes with the engine doesn’t have a temperature gauge. Seems we needed to spend more money for this basic feature. We motor our at our standard 2500 RPM with no issues. Push it up to 2800, things seem time. 3000. Things “seem” fine, but Shannon notices it smells hot from below. I run down to check and I physically measure the engine at over 210 degrees, this is too hot and barely below where the alarms should be going off. (Also something we would have seen if we had a damn temp gauge). She cools off again almost as soon as we reduce RPM back to 2500. We limp back to the dock and call Judson. He spends days diagnosing and tracing the coolant system. We also ordered and installed a temp gauge. Only issue we can come up with is the raw water through hull is ⅝” where beta says ¾” is recommended. Now we need to schedule a haul out and install a new through hull. We opt to go all the way to 1” as the rest of the system is 1” based.
Another week of work and we are testing again. This time with Judson aboard. Same issue. 3000+ RPM and she starts overheating. Lots of research and another full teardown of the cooling system reveals nothing significant. Beta says an exhaust with high back pressure can cause overheating, and because this is a custom built exhaust we have to test. Days of research later we built a rig and tapped a hole in our custom exhaust to test. Everything tests good. That’s not the issue. We’re out of ideas and are beginning to worry. The only thing we can think of is we are overworking the engine. We have an adjustable prop, but we discussed with both Beta and the propmaker and thought we had all the right settings. We decided to haul out again and make some changes to reduce the pitch. Several days and another test. This time we can get the engine up to 3550 RPM but she is still running slightly hot. Almost 200 degrees. But because of the improvement we haul out again, make another adjustment to the pitch, and this time we can run at 3600 RPM, full throttle, into the wind, in moderate seas, and the temperature remains a hair above 190.
Finally.
After nearly two months of work (that was estimated at 2 weeks) everything is complete. In the end, the original estimate of ~$22k, ballooned to just over $50k. Most of that was in labor costs as we had well over an extra month of extra work diagnosing issues we didn’t foresee. A few minor adjustments here and there still to be finalized, but overall, it’s done.
Our first major test was the 2022 Harvest Moon. We successfully sailed the race down to Port Aransas, and were happily motoring our way back. About 10 miles outside of Galveston the engine suddenly dies on us. A quick investigation finds a very clogged fuel filter. Of course, the only thing we didn’t replace. I replaced the filter at sea, but it quickly clogged again, it seems the last ¼ of our tank and the constant stirring just made our fuel bad. We have since had the fuel cleaned and replaced the filters regularly.
Early January, we departed Galveston to begin our cruising adventure. Almost 100 hours and 4 days of engine running and sailing later, just 10 miles from our anchorage. The custom exhaust failed catastrophically.
Luckily, we were close enough to get a tow into a shipyard, and Judson was kind enough to drive to Mobile AL and rebuild it. We isolated the issue to vibration and the heavy exhaust resting mostly on a single point. We found a custom exhaust builder here in Mobile that made us a Custom flexible coupling, and hard mounted the exhaust at several points to isolate any more vibration issues.
Soon enough we’ll be back out cruising again, hopefully with all these kinks worked out!
