Our sail over on friday evening looked like it was going to be one of our first night sails. I finished work a little early, but not early enough to get is to the mouth of the Yealm before dark, so we had both GPSs powered up (one fixed, one handheld), the night vision scope on standby (Christmas prezzie from my sister), and all torches freshly charged. But as we left the shelter of Sutton Harbour (and heard the Maritime Safety Information Broadcast warn of sever gale 9) we soon realised that it was going to be a fairly speedy passage.
We left the engine on the whole time (a bit lame I know, but it gave us a bit of peace of mind knowing that if something happened, we could quickly motor to windward and drop the sails) and put out a well reefed main, and a quarter of the jib. Wind was on the starboard quarter initially, then directly behind us, so we goose-winged and managed a top speed of 9 knots over the ground at one point - a new record. When we turned around the little Mewstone to head to the mouth of the Yealm, the wind was on our port beam. And now that we weren't running with the wind, the strength we experienced increased dramatically. The amemometer showed a max (that I saw) of 38 knots - and despite letting the main and jib well out - we heeled over a lot in the gusts. It was fantastic. Rose seems to love helming most when it's a bit hairy.
Next day we did a walk around Yealm head, and back into Noss Mayo. It was glorious.
On Sunday we had to bash out against a rising spring tide, and into a light wind on the nose. Was fairly obvious we'd be motoring all the way. Another boat had stayed the night with us on Saturday, and they left about 20 mins after us. As we rounded the Mewstone, they undertook us, and with a cheery wave rapidly disappeared off into the distance, back to their mooring at Cargreen. We chugged our way along at about 4 knots (following my hand bearing compass passage plan which worked very nicely) with white smoke increasingly billowing out the back.
We've had increasing amounts of white smoke over the last month or two - and I was almost convinced it was due to the cold weather, and something specific about the design of our Beta Marine engine - but this time it was definitely more smoke at less revs. If we stuck to 2000 rpm, the engine temp seemed stable at 80C, and the smoke minimal. It used to be that we could run at 3000 without smoke or temperature rise. So I concluded it must be a developing problem.
Back in Sutton Harbour, I got out the tools and took out the heat exchanger matrix. I'd checked the inlet strainer and impeller in the past - they were fine - so this was the last piece in the puzzle. Now I'm not very experienced with engine maintenance, but I feel strongly that it's important that I do as much of it myself as I can - because if something goes wrong at sea, you can't easily call out a marine engineer. So it was with some trepidation that I began to undo jubilee clips and remove the various hoses that needed to come off, before undoing the two bolts that hold the heat exchanger together. A little jiggling later, and I had it out. It's a cylindrical object made of copper (I think) with perhaps 50 separate copper tubes running through it. Seawater is pumped through these while the engine's internal coolant is cycled over it at a controlled rate (controlled by thermostat) - so the two fluids are separate, but with a very good thermal connection between them. Turned out that there was an absolute load of calcium built up inside the whole thing. Most of one half of the tubes were blocked, and so was the inlet for the seawater. Fantastic - I'd got to the bottom of the problem. Another hour later I had, using pipe cleaners, wire, drill bits and a bradall, removed all of the calcification and re-built the engine. After a wee problem with an air lock in the coolant, I had the engine running hard astern (while in our berth) sounding quieter than it ever has done (more water in the silencer) and a flow out of the exhaust like nothing seen before - and a running temperature of 70C, not 80+ as we'd got used to.
Feeling very manly, and rather tired, I settled down to listen to the folk hour on BBC radio Devon.
Here's some pics of our weekend...
Me in my Guy Cotten super stylish oilies
Rose in her cheapo Musto suit (no style)
Isabella on the Yealm bottom visitor pontoon
Snow on deck on Sunday morning
