ENVOY’S END OF SEASON TECHNICAL ISSUES – PART 1

We are home in Auckland, New Zealand, for the northern hemisphere winter, while Envoy is in Greece's Lefkas marina.
There is so much technical activity at the end of a season’s cruising that I’m only going to mention specific problems or items of interest, and not the myriad of routine jobs such as oil and filter changes. Even this is going to require a couple of postings.
The contractor we selected to assist us, Sailand, have a great team and we met four of them – the owner/manager, a diesel mechanic, an electrician, and a general mechanic.

At a meeting aboard Envoy with the manager to discuss the whole work program, and what needed to be done before Envoy was lifted from the water, he made some excellent suggestions including running the two seawater cooled engines (wing and generator) plus all seawater pumps with fresh water and then glycol, when Envoy was on the hard. We’ve not done this before, but we thought removing all the salt from the systems was definitely a good idea. When we did this later, it took about four hours.

Firstly the diesel engineer checked out Envoy’s issue of the main Lugger engine running too hot at high (above 1,800) rpm. After the engineer inspected the whole system we started up the engine and went for a sea trial. The engineer made some adjustments to a bypass valve on the keel cooler, and the engine ran much cooler; in fact I was able to take the rpm up to 2,000 without over-heating, which only started at 2,200 rpm. I’m not sure at this stage how he achieved this, and will check this out further on our return.
To put this issue in perspective, Envoy generally cruises at 1,450 – 1,650 rpm, and has no over-heating issues at those revs, but now we will have a much wider operating rpm window. The engineer wants to make some further adjustments and check the thermostat and adjacent areas. The objective is to be able to run at wide open throttle (WOT) of 2,400 rpm without over-heating, but Envoy has never done that, even with the previous owners, and provided we can run up to 2,000 rpm without over-heating I’ll be happy.

He also checked our starboard forward 860 litre capacity diesel tank that has been ballasted with bottled water since a leak developed early last year. The problem here is lack of accessibility, although there is an inspection hatch on the top of the tank. The engineer plans to use a small remote video camera to inspect the seams. The camera’s image is expanded using a laptop to find any cracks and holes. This sounds very clever, and we hope it works. We don’t need the additional fuel capacity (with 2,900 litres of capacity in the other three tanks) but I do want to get it repaired and back in use to avoid corrosion, and to better control Envoy’s trim.

The electrician checked our non-working Robertson auto pilot. Envoy has two independent autopilots so this failure had not been a problem for us. I had assumed (never assume!) this failure to be an electronics problem, but the engineer quickly found it was a 12 volt motor problem – it’s only running intermittently. So this will be removed and serviced or replaced.

He also removed our 27 foot long SSB whip aerial, which is getting badly frayed, and this will be repaired during winter.
A damaged Garmin GPS antenna was also removed for repair (this was damaged by our boat cover resting on it during last winter).

Next post will cover other technical issues to be dealt with during winter, and “guardianage”.