Well it’s been cold! But we have had 4 short trips out, mostly between Ferry Nab and The Jetty museum, and around Belle Isle. But while the high pressure has delivered lots of sun , it has provided absolutely NO wind!
St Georges Day
We met some SBA folk at the Jetty Museum, and wound up playing “ferry” and bringing a crew of 7 back to Ferry Nab…. in the process we proved a number of things…
Heading south with a full crew…
- The boat rides on her lines with 7 on board! This suggests that we should shift some of the pig iron ballast towards the stern. …and that the weight empty must be around 2.5 tonnes.
- The lake is very low, after a dry April.
- The north side of the channel into our berth is VERY shallow
- The old Searfarer 5 depth sounder, is being a little unreliable.
…the net of the last three items is that we ran aground twice in as many minutes!
This, and the difficulty Lou has making sense of the flashing echo lights on the ageing echo sounder, have resulted in us investing in a digital NASA Target2 Echo Sounder display, which gives big readable numbers and a louder alarm!! (It should be noted that Lou was not at the helm, and the warnings of shallow water from the “engine room” were insufficient to avoid the collisions with the bottom! )…
The nice thing about the NASA display is that it works with the existing transducer. So Befur moves further into the digital age!
But some pushing with a boat hook and a lot of “full astern” re floated us with a minimum of drama….
A nice trip, and a demonstration of Befur’s carrying capacity.
Meeting Obsidian & Clutch Trouble
A trip out to check and calibrate the new echo sounder, resulted in us meeting up with Russell Clements and Obsidian for the first time this season.
While rounding Belle Isle, the engine becomes more noisy and I realise the sprag clutches on the lubricator are slipping 😦 …I had seen this happen last year, and failed to do anything about it – idiot….
It is quite well known that needle roller sprag clutches do wear the shaft they operate on, and this should be hardened. Befur’s is hardened silver steel, but clearly not hard enough, and 3 seasons marked the end of it’s serviceable life. This was probably aggravated by changing to 440SAE oil in an attempt to lose my “noisiest boat in the fleet” tag.
The 2nd factor is probably that the ID of the clutch is quite small (6mm dia). So, the plan is to switch to a clutch bearing with an inner race (to avoid the need for hardened shafts) and choose a larger ID (12mm) to reduce the sheer loads on the clutch. Hopefully this will be a more permanent fix.
The current plan is to remove the engine at the end of the season, for a “major shopping” and see if we can quieten down the plant by ensuring all the bearings and clearances are suitably tight. At this point I plan to replace the plain bearings on the piston rod with more needle roller bearings to cope with the stressful location and limited lubrication.
We are also due our next boiler test in June, so at that point I will increase the burner jet size to 2 GPH (gallons/hour). Currently, we are running a 1.75 gallon/hour jet, and this is the limiting factor in boat performance, and also seems small by comparison with other similarly sized boats.
We will also take the opportunity of removing the engine to see if we can improve the sealing of the valves in the edwards air pump, and perhaps replace the condenser with a larger one, in the continuing search for the elusive vacuum.
So while the new season has provided some challenges, it has been positive, and we look forward to enjoying the summer on the lake.