Engine planning; chartplotter & GPS

I finally managed to get my first quote for the repower job, from the Singaporean mechanics who came to look at the boat last week.  The quote is fairly sparse on details.  The lump sum labor cost is quoted as S$6.5k for removing the old engine, figuring out and maybe welding custom mounts for the new engine, doing some testing of the new engine at the shop, installing the new engine, and doing a sea trial.  Although we discussed other stuff I want to do like replace the engine plumbing, clean and paint the bilge, etc, I don’t think that’s included in the quote (awaiting clarification on that).  Nor is the cost of a haulout; you don’t have to haul the boat out to repower but it probably makes things a lot easier.  Coupled with the cost of the engine (probably around US$12k) and all the auxiliary work and random things that will crop up, I think doing the job in Singapore will easily hit US$20k.

Next up I need to get quotes from shops in Langkawi and Phuket and see how big the difference is.  If it’s huge, I’ll go through the hassle of bringing the boat up there with the current half-working engine.  If the difference is small, I’ll probably just go ahead and do the job here, where it can be done faster and I can have some time to give the new engine some workouts in close proximity to the mechanics.

I am still agonizing over which engine to order.  There are way too many variables.  I really like the Beta 38 in some ways, but the higher wide open RPM (3600 vs my current engine’s 3000) means the torque is less and I will likely need a new propeller.  I am in contact with the local Westerbeke distributor regarding the 44C Four which peaks at 3000 RPM; I’m hoping to get a quote from them soon.

Earlier in the week I spent a couple hours measuring the engine bed and bearers to the best of my ability.  Last night I put together a quick and dirty profile of the engine bed, got some drawings of the engines I’m looking at, and scaled them to match.  Here’s what they look like assuming I want to keep the same prop shaft coupling placement.  In the drawings, the top crosshatched area is the cabin sole; the bottom one is the bilge; and the angled one in the middle represents the bearers, which are inconveniently angled at 4°.

The Yanmar 4JH5E is definitively too tall to fit:

The Beta 38 fits nicely in theory, but I still need to make a lateral drawing to be sure it’s not too wide for the bilge.  I think it should be fine.  There is a shallow sump option but I don’t think it’s necessary:

The Westerbeke 44C Four is similar to the Beta 38 — actually, even a little smaller:

In all cases, the upward angle of the bearers, plus the down-angle of the prop shaft (~5° as best I can tell after a few measurements and some trigonometry), makes the question of how to mount these engines a tough one.  Most engines have a down-angled transmission option that may simplify things a little.  For example, there’s a 7° down-angle transmission for the Beta 38, which would mean the engine could actually tilt forward 2°.  That’d align the rear engine mount quite a bit more evenly with the bearer.  But in all cases the existing bearers are higher than the stock mounts, so I’ll definitely need to fabricate custom mounts.

As I mentioned earlier I still need to make lateral drawings to see if stuffing the engines so far down in the bilge cavity below the bearers is even feasible.  In the worst case I may just have to rip out my bearers and build new ones.  There is also some question about having the center of mass of the engine back a foot or two behind where the current engine CoM is, but one thing at a time.

I also heard back from Lowrance about my GPS trail exporting issue.  It took a little explaining and demonstrating on my part but I was able to get them to reproduce the crash bug I encountered.  Here’s hoping they fix it.  But in the meantime I hacked my way to another solution thanks to gpsbabel.  After some tinkering with Google Earth, here is a map with most of the sailing Oia‘s done since I bought her:


View Larger Map

There’s a bigger and easier to navigate version here.  The GPS trails are a bit spotty, partly because I didn’t have the chartplotter for a lot of the sailing; and partly because we kept forgetting to record trails while we were sailing around Tioman.  I filled in the blanks with estimated trails (in pink).

Not nearly enough sailing for one and a half years of boat ownership, but soon that will be rectified.

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