@arild-jaeger
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Ron,
Would that be the boat of Beate Kammler’s “Komm, wir segeln um die Welt” book about her circumnavigation? (in German, available at Amazon)
Beate sounds like a sporty girl in the book. I seem to remember her describing herself at the outset of the journey as “I was 25 years old and ‘durchtrainiert'” – what would that be in English – thoroughly fit? I also recall that both she and her husband had their appendixes profylactically removed before their journey (hope this is understandable in English)…
Regards,
ArildPS: here is a link to Beate Kammler’s web site:
Marilyn,
I decided that the intermediate shaft with flexible couplings at each end would absorb a little misalignment. Anyway it was difficult to measure alignment when everything is flexible…
It seems to work fine, but I guess the end result of any misalignment could be increased wear of the bearings in the gearbox and in the stern tube. If the misalignment is really bad, I suppose other things could happen as well.
Arild
I replaced the engine mounts when I replaced the white metal bearing. I put in Yanmar mounts, but they are a bit too high, so you will probably need different ones to fit correctly (depending on your exact measures). The original mounts were very stiff after 40 years…
Van,
I found my old test data, which show a maximum RPM of 2800 giving a speed somewhere between 7.3 and 8.0 knots (GPS / Sumlog). I don’t know how to upload the excel file to this site, but the key data are:
Engine GPS Sumlog
RPM Knots Knots
890 3,1 2,0
1 090 3,7 2,8
1 350 5,5 4,4
1 700 6,0 5,8
2 010 6,6 6,7
2 250 6,8 7,1
2 500 7,0 7,7
2 800 7,3 8,0We also measured the bollard pull at different engine RPMs:
Engine Bollard pull
(R.P.M.) (kp)
890 45
1000 60
1100 68
1200 84
1300 95
1400 115
1550 136
1750 180
1910 212
2070 250
2260 295
2410 340
2500 365Finally we tried to measure the towing force at different speeds (not very stable results, but a good indication when you plot the results):
Speed Resistance
(knots) (kp)
2,0 32
2,0 38
2,4 50
3,3 60
3,6 40
4,5 148
4,6 90
5,0 70
5,5 100
5,8 100
6,2 150
6,2 100
6,2 125
6,4 180
6,5 200
6,5 200
6,6 150
6,7 200
7,2 210If someone can help with uploading the spreadsheets, you will also see the related graphs.
Kind regards,
ArildHi Van,
Our Nic 38 has a Perkins 4.108 (which I believe is 49 hp) with the TMP 12000 gear and the old 16″ X 12″ three bladed propeller. We normally cruise at 2000-2100 engine rpm giving us about 6.5 knots. I think the max rpm is in the region of 2800-2900 taking us to 7.5-8 knots. I probably have a diagram somewhere which I will post later. My propeller is probably from 1968 and is pitted to the extent that there are some small holes through the blades. Still, I have no plans to replace it.
I think the pitch and diameter are well suited to the boat.
The propeller has a very uneven inflow of water from the front side with a short distance to the relatively wide deadwood. This will reduce the efficiency of the propeller. Also the distance between the propeller blade tips and the hull is very small, which means there will be a lot of noise and vibration. To reduce the noise you could reduce the propeller diameter to increase the tip clearance, but this would further reduce efficiency. You could also increase the number of blades on the propeller and use scewed back blades, both these measures would reduce the impact on the hull of each blade passing and thereby the noise and vibrations.
Regards,
ArildMarilyn,
On Far Out, which was built in 1968, there is a white metal bearing (and no cutlass bearing). I found that the difficult parts were (i) to get the propeller unstuck (had to use heating and a heavy duty puller), and (ii) to find a workshop that could machine the tailshaft to become completely “round” and to mould a new white metal bearing in the stern tube to fit the shaft.
If the shaft doesn’t move up/down/sideways when you rock the propeller, I would just leave it.
If you want to change it, you will need to take off the propeller, remove the intermediate shaft and pull the tail shaft into the boat. Then you unscrew the two bolts holding the end-piece of the stern tube before you unscrew the end-piece itself and then you can unscrew the stern tube (from the outside). Having the tail shaft and the stern tube, you just bring them to a workshop that can help you (not many of them around, so I would start by finding one before disassembling anything).
I will e-mail you some photos and a simplified drawing, which you may post here for me if you like
Kind regards,
ArildJeff,
Far Out also has two wing tanks used for diesel. There is a deck filler for each of the wing tanks. Each wing tank then has a pipe leading down to the centre tank. I normally start by using the dip stick in the centre tank to find out how much fuel I need to add to it. Then I fill it with the specified volume through one of the wing tanks. As it takes some time to get it all down from the wing tank to the centre tank, I then proceed by filling the other wing tank (with the valve leading to the centre tank shut) before I shut the valve from the initial wing tank and fill it up.
I think all three tanks have separate vent pipes.
To really top up the wing tanks, I occasionally open the inspection lid on the top of each wing tank and fill through those instead to see what is going on inside each tank.
And – as a side topic – I always add the DFT 1500 Hammerdown fuel additive.
http://www.dft1500.com/testsuscgnoaa.htm
When I worked at the ship engine laboratory at the Norwegian Ship Research Institute (now Marintek) one of my colleagues tested all kinds of fuel conditioners, etc., including the use of magnets along the fuel pipes. He found that DFT 1500 Hammerdown had the best effect.
Kind regards,
Arild
