Thursday, 28 August 2008

Day Twenty-Seven-Why didn't we buy a boat with a bigger engine room?

St. Pancras Lock- Little Venice

Grand Union Canal

5 miles, 3 locks

In which the Duck and its crew spend all morning realigning the engine, discover the joys of Loctite, become the centre of attention whilst locking through Camden, and rejoin the Warriors in Little Venice; and a Cunning Plan is formulated.

The alarm went, and I felt hungover. Although I'd not been drinking. Perhaps staying up late last night reading a Bill Bryson book wasn't the best plan...

St. Pancras basin

The first job was to realign the engine. We had a few attempts, foiled each time by the bush of the oil seal. It's got various welds upon it, from where it was attached to the face of the flexible coupling, although it's now sheared off; we had a rotational jigsaw getting it back together. It took a few hours to get the engine just right, but once everytign was aligned properly, it went together reasonably quickly; the 50mm grub screws are now securely in the shaft, Loctite-ed in place (although two will have to be re-glued) and this temporary repair should hopefully hold until we can get to Bill Fen.

Why didn't we get a boat with a REAL engine room...?

Afterwards, we went to St. Pancras station to admire the architecture and buy some lunch; hot pasties followed by biscuits from M&S to restock the Cake 'Ole- so named because "'Ole" is a specific old fashioned boating term- "Bed 'Ole", "Engine 'Ole" etc.- hence the name for our cake drawer, and our Laptop 'Ole, which isn't particularly traditional either!

We then headed back towards Camden. When locking through, we attracted the attention of a family of interested Chinese tourists, and I answered their questions as we locked through; it was rather endearing, as whilst the average British curious passer-by tends to know a little bit about the canals; this family had, understandably, not even this background knowledge, and so were asking questions about why the boat was so narrow, how locks worked, and other related subjects; I reckon I could be a tour guide without too much retraining... At a later lock, we met a Canadian chap whose boat we'd passed back in Northolt, and he helped Amy with the particularly low, stiff gate. We also had assistance from the crew of NB Tarporley, who Warrior had seen yesterday. The top gates were stuck together and wouldn't respond to any amount of pushing by hand; however, a slight nudge from the boat was enough to separate them and allow them to open.

Amy doing her best to mimic a Cotton Traders advert...

Particularly grand mansion in Regent's Park

I dropped Amy off at Camden, and she headed into her ex-place of employment to collect a cheque for the money she was owed- most welcome!- and, by the time she'd returned to Little Venice, I'd moored up and was happily on Warrior having a civilised chat over tea and biscuits! Another option to repair the propshaft is to have the new one over-long, and bolt it directly to the gearbox spider, until we can fix the flexible coupling or get a new one. That would give us a few more vibrations, and the engine would have to be better aligned, but at least it would be a lot more dependable! We talked about Bill Fen marina and boatyard, and the possibility of using their slipway to take the Duck out of the water and fit the new shaft. We'd probably also fit a mesh over the raw-water intake to prevent any further problems!

Little Venice

The three longer grub-screws we put in are holding for now; as long as we keep an eye on them, and check them every couple of hours to nip any working-loose in the bud before they can allow the shaft to spin, they should be alright. I did have to tighten two of them, so I'll probably re-Loctite them tomorrow morning before we set off and see if this helps.


  1. Hats off to you both each time a problem emerges you seem to rise to the occasion and put it right.

  2. This has been a bit of a baptism by fire hasn't it? Well done to both of you for keeping so positive - you will laugh at it further down the line of course but for now it must seem a bloody nuisance. Best Wishes
    Nb Caxton

  3. The more I think about it, the more I'm convinced that your "oil seal" is a thrust bearing. Why would there be an oil seal there, except to keep lubrication in a bearing? If it has a bush which was welded, that could be how is was attached to the coupling/shaft, and the root of your problem is that it's no longer attached.

    The axial forces from the prop will be much larger than the rotational forces from the engine. (It's roughly the same power in each case: power is force-times-speed: how much faster is the shaft rotating than the boat moving: that's the ratio of rotational to axial forces.) Plus axial load on the coupling will distort it and mis-align everything.

    If I'm right, the key to solving the problem is re-attaching the bearing to the shaft. Carrying on as you are is doomed to fail, and risks totally wrecking the coupling from out-of-spec axial thrust.

    Email or phone me if you need to (Jim and Sarah have my cellphone number.)


  4. Moominpapa I think you are right. The piece of steel is a machined collar which fits into the stern greaser and fits tight up against the back of the flange of the Centraflex coupling, but was obviously an addition (The Centa catalogue doesn't show any such bearings). The collar wasn't fixed to the shaft. The main problem James and Amy are facing, is that the prop shaft is worn, and the cone shaped flange of the Centraflex coupling cannot be tightened enough to grip the shaft. The grub screws are in some holes which have been drilled through the flange of the coupling perpendicular to the shaft. There is a hole for one of the grub screws to locate in, and there are two small dimples for the other grub screws. This just about works when going forward, as the prop pushes the shaft into the coupling, but when in reverse, the prop is pulling the shaft out and loosening/shearing the grub screws. Basically it is a bodge! The only real fix is a new shaft and flange for the Centraflex. James' Dad.