Machinery upgrade

One of my first planned projects on Pirramimma was to change the impeller covers from the existing ones fitted by the engine manufacturers to new SpeedSeal covers. It only took me about ten months to get around to it, and of course the impeller on the genny destroyed itself before I had done the work, as noted in my earlier blog.

The idea of the SpeedSeal is threefold.   Firstly to increase the lifespan of the impeller by reducing friction, secondly to reduce the likelihood of the impeller disintegrating in the event of loss of cooling water from, for example, a blocked water filter, and thirdly, to enable a quick change of impeller when it is necessary.   

When you open the package, this is what you get:

Silicone lubricant, 4 s/s hand screws, O ring, cover, PTFE bearing, impeller removal tool

The first thing you notice is that there are only four hand screws whereas your impeller housing probably has six screws.   This is not an error; you only need four.

This is the generator housing in the engine room and I must say that it is a complete luxury to be able to work on a marine engine when access is as easy as this …
  

      

generator box

              

… with part of the cover removed

First thing is to shut off the raw water seacock:

closing the seacock

The generator is a Fischer Panda with a Kubota engine and the pump - this one is a Johnson - couldn't be easier to get to:

The Johnson pump as supplied - nearly

… which is not to say that it is impossible to drop one of the screws.   In the picture above you can see 5 original screws plus one hand screw. (The sixth screw is somewhere under the engine which, as we all know, is where they think they belong).   I dropped the screw when I was replacing the impeller earlier in the summer.

Undo the screws and remove the plate.   This will expose the impeller which you remove by whatever is your favourite method.   The little red plastic 'impeller remover' that came with the SpeedSeal kit didn't really work for me.   There is probably a knack, which I didn't have.   I will have another attempt next time I have to do this job.

Damaged impeller

The object of this exercise was merely to replace the cover, but when I exposed the impeller, this sight was a bit of a shock; you can see that all six vanes are split.  The impeller had been in for 63 days with only 22.5 hours of use.   After discussing the issue with my friend Diederick, he thought that it may have failed from too much water pressure caused by a partially blocked heat exchanger, and/or the pipes leading to it.   I borrowed an industrial strength wet & dry vacuum, modified the business end with a short length of hosepipe, and managed to extract several bits of debris:

bits of old impeller removed from the cooling system

Once the old impeller is out, the inside of the impeller housing is exposed.   This you coat liberally with some of the lubricant supplied with the kit.

The empty housing showing the shaft that drives the impeller.

Smear the same lubricant over the new impeller and insert, making sure that the vanes are compressed the correct way.   On this pump, the water flows from top to bottom so the impeller rotates clockwise.

The new impeller in place.

When you see the impeller in its housing like this, you realise how much of a thrashing they get during their working life.

Taking the new SpeedSeal cover, you again coat all the inside bits with the lubricant, insert the O ring into its groove, place the PTFE bearing in the middle, cover it with the metal plate and offer up the whole thing to the pump housing.   The lubricant holds everything in place, so this job is blissfully simple - nothing drops out.   Slide the new cover over the two hand screws which you have partially screwed into the housing:

New cover 

The clever bit

The inspired bit of thinking about the SpeedSeal is the fact that the two lower screw holes are actually slots which means that the cover is slid on and off the housing; only the top two hand screws need to be removed.   This makes replacing an impeller a two minute - or less - job.   Unless, ahem, you need to find bits of the old impeller.

Insert the top two screws after adding a dab of lubricant to them, and tighten by hand, going round three or four times to take up any slack as the unit beds down.

Tightening the hand screws

Finally, open the seacock, start the engine and check for leaks.

Final job is to open the seacock.

It works.

The blessed sight of gallons of water sluicing through the filter!

Here is one last picture of the second new SpeedSeal fitted to the main engine, which is a Perkins.

/Rich.

Final cruise of the year

27 October 2015

Before laying up Pirramimma for the winter, we decided to take a final cruise around  - or more accurately, through - part of Flevoland.   The Province of Flevoland was eventually incorporated in 1986 and is made up of the three large polders that were drained in 1939, 1957 and 1968.   On this trip we travelled through the south west and south east polders. One of the interesting things here is that the Dutch decided to keep this 'new' land separate from the existing coastline.  Effectively this means that they have created a large island.  This has multiple benefits including the easier management of water levels, keeping the former coastal towns accessible from the water and, not least, creating a massive water playground (The Randmeren) which is hugely appreciated and used by locals and visitors in their thousands.

One of the results of land drainage is that the resulting dry(ish) land shrinks and lowers.  The Randmeren water level is already a couple of metres below Mean Sea Level so when  the polder was drained, the resulting land was another two or three metres lower and the drains they had to dig to remove the water are obviously lower still.   So when we lock into Flevoland the drop is 5 metres, large for Dutch waterways.   There is a warning on both sides of the lock.   "Let op!" means 'Watch out!'

Warning sign at the lock.  The large building is a pumping station.

We entered the lock and had a gentle descent - all automated, including the VHF/phone system used to register our presence.

Crew waiting with a 15 metre line...

At the bottom with the gate just opening.

Looking back at the lock.

The land/waterscape we now entered was completely different.

Looking astern ...

… and ahead.

On this stretch of water, between the lock and the town of Almere, there are two fixed bridges marked as 3.9 meters.   With our mast down, our air draft is 3.6m.  The water level looked 'normal' but we had no way of telling the exact air draft until we approached the first bridge, which we did … very slowly.   With barely any way on, we inched under the bridge.   My guesstimate was that we had about … 30cms to spare; the bridge heights are correct!  Sigh of relief, as our only other option would have been to turn around and go back through the lock and into the Randmeren again.  We approached the second bridge with some confidence but the bridge looked to us to be a bit lower, although it is incredibly difficult to judge bridge heights from the deck of a boat - they always look much lower than they actually are.   So, exhibiting our usual caution, we again slowed to a crawl.  Though the bridge was definitely lower than the 3.9m published height, there was - just - enough room for us, having quickly whipped out the ensign staff, which is the highest part of the vessel.   Two bridges within a mile of each other with the same air draft marked on the chart, but different actual heights.

We motored on and in due course moored up at a nature mooring a mile or two south of Almere.

Last of the evening sun.

We had two more nights in Flevoland, one at another nature mooring near Lelystad and the second at the WSV (Yacht Club) in Dronten (excellent).  On the forth day we had two locks in quick succession into the Ketelmeer and thence back to our berth in Elburg. 

Arriving at the Ketelsluis

And of course this time we had a 5 metre rise to get back to 'normal'.  I remember the first time I sailed to the Netherlands (March 1991) I found it somewhat surreal at IJmuiden to lock down from the North Sea into the canal to Amsterdam.   It still feels slightly odd to be so far below sea level.   I suppose it's normal to the Dutch; you certainly have to admire their hydraulic engineering skills. 

Inside the lock.

On our way home we passed this chap - they really load these barges to the limit:

Arrived at Elburg around 1500 having covered 68.5 miles over the four days.

/Rich

Urk to Elburg

27 September 2015

This morning dawned bright and sunny with, again, a near total absence of wind.   We had a stroll around the town taking a few snaps.

Early morning sun on the breakwater at Urk

Looking North towards Lemmer and Friesland

The famous lighthouse in Urk

When the Ijsselmeer was the Zuiderzee, Urk was an island and therefore this lighthouse was of great navigational importance.   We think that is is great that it has not been decommissioned and still shines out every night.   One flash every 5 seconds with a range of 18 miles - nautical miles, that is (33km).

Back on the boat for a coffee and just before noon we cast off our lines for our trip to Elburg.   

Departure from Urk

As we were not in a rush we kept the revs to just above idle (850rpm) which gave us a sedate 3.2 knots.   It also meant that we could barely hear the engine.   At 1245 we went under the Ketelbrug which carries the A6 motorway.

Looking back at the Ketelbrug

Locked through the Roggebotsluis at 1515 and, having upped the revs a bit, arrived at the town quay in Elburg at 1700, five hours and 18 miles after we left Urk.  We stayed three nights on the town quay for €17 per night with coin-operated electricity at 50c per 'unit'.

Alongside at Elburg, halfway through the first beer.

Same place

Pirramimma catching the last of the evening sun

Flat calm

Next morning was a bit different:

Misty morning

… but it soon warmed up to another flat calm and sunny day with a great sunset again:

Late evening, Elburg

/Rich

Lemmer to Urk

After our three nights in Sneek we had planned to spend one night in Sloten before returning to our homeport of Lemmer.   The forecast wasn't brilliant, but we were going anyway and would see how things panned out.   It was grey and overcast and once we had cleared the shelter of the town, we had the pleasure of a good 20 knots on the nose with rain.   Nonetheless, we carried on with our plan and approached one of the nature moorings just South of Sloten. This was a repeat of the fun we had at Adam Island and again had to heave the boat upwind on the warps until she was secure on the pontoon.  Half and hour of effort, but we got there eventually.   Lunch was leftover hot chicken pasta and was excellent - just what we needed on a day like today.  

Two hours later it was still blowing and WindFinder was predicting 30 knots.   The pontoon, in our opinion, was a bit rickety and the silly little rings to which we were attached were already beginning to pull out of the semi-rotten timbers so at 1620 we made the decision to clear off back to Lemmer.   By 1730 the breeze had eased somewhat but squally showers remained.   On the approach to Lemmer we could see a thick black line squall so reduced the revs to 1000 to allow that mess to blow through and as we arrived at our berth only light rain remained but better still, barely a breath of wind.   We calmed ourselves down  (and warmed ourselves up) with a Hibiki for the Nav and a Whiskey Mac for the Skip.   

For our trip out of Lemmer we couldn't have asked for better weather - a blue sky and almost no breeze; maybe pushing F2 on the Beaufort scale.

Lemmer, with a display of ex-lifeboats including an old RNLI vessel.

There were a lot of vessels clearing out of the town and onto the Ijsselmeer, no doubt to take advantage of the beautiful late summer weather, so it took us about 40 minutes to get through the bridges and lock out of Frisian waters.

Locking out (up!) of Lemmer in to the Ijsselmeer

Looking back towards the town

Locking out of Friesland is a rise of less than a metre; not much, but holding back an awful lot of water...

It was great to be out on open water once more.

The open waters of the Ijsselmeer

We increased the revs to 2000 to give the engine a good blast and a boat speed of 7 knots.

Steaming along

Two hours later we were in the outer harbour in Urk and moored up by 1415.

Moored in Urk

These are really good solid high quality moorings with built-in electricity and water.

We took a stroll around and onto the beach in the late summer sun.

We ate out tonight at 't Achterhuis - 60 metres from our mooring and a 1.3km walk through the town.   The place was packed.  From our table we had the interesting sight of a fleet of UFOs coming into land:

UFOs over Urk

… and were treated to a magnificent sunset:

/Rich