We returned to Mazatlán late this past summer, not only to hide somewhere for potentially the worst part of hurricane season, but also to visit the fine mechanics at Total Yacht Works. They'd done work for us before and the timing of our return coincided nicely with Yanmar's recommended 2000-hour engine maintenance, so we decided to throw the work their way.
The situation with the engine had all started innocently enough. During the past year GB had observed an increase in oil consumption, especially at high rpms but negligible at low rpms. When we'd had the oil cooler replaced in the summer of 2008 these and other engine/oil symptoms improved. However, during June and July 2009 as we were cruising the northern half of the Sea of Cortez, GB noticed that the oil consumption problems were back, and increasing. I'd noticed black smudges on the fiberglass around the outer exhaust vent, but frankly I'd seen those smudges for so long I thought it was normal. GB kept his concerns about the engine to himself – not wanting to cause me any worry, he later alleged. Instead, during July he started needling me about being impatient for the entertainment of the big city, and not wanting to spend any more time on the hook in the Sea of Cortez in "all these anchorages that look alike." What a smooth talker.
The Fox and its Yanmar 4-JH3 did us proud. Got us back several hundred miles to Mazatlán with no apparent problemo. After we returned from our August road trip to Morelia and Pátzcuaro GB arranged with Total Yacht Works to perform not just the 2000-hr. routine maintenance, but also a compression test to determine the cause of the oil consumption GB had been seeing. Meanwhile we wanted to check the condition of the bottom paint which seemed to be flaking off in areas so we were prepared to have the boat on the hard for some hull work, too. All told, we thought the whole deal would be, oh, a 5-day haul-out, splash-back-in piece o'cake.
Yeah, so the next thing we know Bob and Rafael at Total Yacht Works have performed the compression test and are breaking it to us gently that Mr. Yanmar has experienced some significant, long term salt water intrusion and needs to be removed from The Fox for a rebuild – unless, that is, further testing shows that Mr. Yanmar has totally packed it in and needs to be replaced.
Say what?
Nothing corrodes metal faster than hot salt water. Ergo, salt water intrusion into engine equals rebuild. It seems those madcap Swedes who installed the Yanmar way back in late 2001-early 2002, omitted a crucial engine component. Namely, a riser/exhaust elbow that rides directly behind the engine and is supposed to provide a Yanmar-specified 12" vertical clearance between the engine and the muffler. When a proper size riser/exhaust elbow is installed to specification it prevents salt water from flowing out of the muffler and back into the engine when the engine is not running. The system that was installed on The Fox had a smallish, horizontal, L-shaped exhaust elbow that provided not 12", but less than 6" vertical clearance. The effect of which was, that each time our engine was shut off and we were sailing – especially sailing on a starboard
tack into head seas – the residual salt water in the muffler flowed along an almost horizontal slope back into the engine, sloshing merrily atop the valves, rings and pistons. When the engine was restarted the salt water got sucked back out…most of it. What stayed behind happily corroded the engine valves and piston heads while we traveled hither and yon, our ignorance blissful.
Facing an engine rebuild on a boat that is only 7 years old is suboptimal. However, we'd had a lot of luck. We were lucky to have had Mr. Yanmar go kerflooey after it got us back in to port, right where there were reputable Yanmar-certified mechanics with mad engine skillz, readily available to do the work during a comparatively slow time of year. We were also lucky to learn from Total Yacht Works Bob that had it not been for GB's years of attentiveness to oil changes and topping off the fluid levels whenever they got low, the salt water damage would have been much worse and we'd have had to buy a completely new engine instead of just an engine rebuild. So, thank you, GB, for having saved us the extra $7000 a new engine would have cost us over and above the cost of the rebuild.
Once The Fox was hauled, Mr. Yanmar was yanked out, along with various and sundry associated parts, including but not limited to the propeller shaft, Aqua-Drive system, propeller and stern tube. Good thing all this was removed and inspected: we discovered that the bronze stern tube encasing the propeller shaft had some serious corrosion – likely caused by an accidentally incomplete mixing of metals at the foundry, Bob guessed. So, we added a new stern tube to the list of parts that needed ordering.
We usually stay aboard for an ordinary haulout, but not for this one. With everything in the engine compartment being worked on, the stern cabin was commandeered for side access and the companionway steps were removed for front access. All that stuff had to go somewhere, which meant the salon and the V-berth were chock full o' cushions, wood steps, and other artifacts. Daily liveaboard life was now impossible, given the space limitations alone. Not to mention the grinding and sanding work going on – on The Fox and other boats; as well as the bulldozing and construction happening in the vacant lot next door to the boat yard. The weather was still kinda hot & humid. It took GB and me about 5 seconds to conclude we needed an onshore domicile for however long all this work would take – and at this point, nobody could estimate that. Thus, we selected an excellent dwelling conveniently located near the boat yard, bus lines, restaurants and mini-marts: the Bungalows Mar-Sol – we scored a pad with a king size bed, a mini-split air conditioner, a flat-screen TV with cable, and a fully equipped kitchen. All for about US $28/night. Awesome.
Once again life was showing us that there is hardly any problem that cannot be resolved with large infusions of money or time. Or in our case, both. Which we'll further discuss in the next post…
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