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Bob & Freddy Tuffnell
KeymasterHi Peter
I can’t reply directly, as my cruising ground is on the West of France. The coast is mainly flat, and usually a good 4G signal will be available at least 5 miles offshore, often quite a bit more.
My comment is that as most mobile customers are wanting increasing speed of data connections for watching videos, and stuff like that, the technology is trending to using much higher radio frequencies : 4G uses 700Mhz to 2. 6 Ghz (wavelengths 40 cm to 11 cm). Now 5G is being deployed, most often using 26Ghz (wavelength around 1 cm). The distance that the signal can travel is (amongst other factors), depends on the frequency. Remember that the defunct Radio 4 LW transmitter at Droitwitch used 198Khz (1500 metres wavelength), and could be received over half of Europe. Our marine VHF radio is 156Mhz, which is around 2 metres wavelength, and ( if the aerials are high enough) will usually cover 10 to 25 miles.
Bob & Freddy Tuffnell
KeymasterIt could be corrosion on the impeller on the primary water pump (the one on the engine block, which is driven by the same belt as the alternator). I assume that basic ideas like thermostat operation and specifications have already been checked? Otherwise you could suspect scaling up of the water galleries, especially if repeated overheating has encouraged topping up with tap water instead of antifreeze solution.
On my BMC1.5, I have fitted a pressurised overflow tank, so the heat exchanger stays 100% full at all times. The spring loaded pressure limiting cap is on the remote tank. I found one that was originally made for a Rover 2600, but the same thing was installed on many other cars.You must be logged in to view attachments.
Bob & Freddy Tuffnell
KeymasterCan’t help to find you an engine mechanic, but here are a couple of ideas to follow up:
Pretty unlikely to be coming from the raw water pump as there are 2 seals on that drive shaft: one to keep the oil in the sump, and the other to keep the water from getting out of the housing of the impeller. In between the two, there is a vent hole, and if one or the other is leaking, the respective fluid will be dripping out into the bilges.
The most likely issue is with a cylinder head gasket corroded or broken, which allows water from the cooling jacket around the cylinder head to get into the space where the valve rocker push rods go to the very top of the engine, and the oil that is fed under pressure to the rocker shaft drains back down to the oil sump.
These engines are very simple, and require no special tools to remove the cylinder heads, with the engine still in the boat. If you, or one of your friends feel up to doing that, you can see on the photo, (where the yellow dots are) the part of the gasket that separates the water from the oil. Any weakness in that area could allow the water to get into the sump.
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Bob & Freddy Tuffnell
KeymasterHi Charles
It’s not easy to give a straight answer as so many factors can change the game:
A lot depends on the propellor. The optimal choice of the diameter and pitch would be influenced by the reduction ratio of the gearbox.
There is also a balance to be found between getting absolute maximum thrust for pure motoring in adverse conditions (when you could run the engine up to the speed of its maximum continuous power rating), and perhaps a slightly bigger pitch propellor to motorsail at maximum hull speed, without having the engine at full speed.
In pracice, if you find that if you gradually open the throttle, until the boat speed no longer increases, then there is not much point in trying to push the engine any harder. Any more will simply increase the fuel consumption and/or make a bigger bow wave for perhaps half a knot extra speed. Same thing if more throttle results in black smoke or soot on the exhaust. Weed or barnacles on the hull or propellor can give the same “overloaded” effect.
Bob & Freddy Tuffnell
KeymasterAs Chris said, open everything that can be opened, unscrew any fixed floorboards. If you have power, and access to an electric dehumidifier, that is a good idea, preferably with the water drain going out through the sink drain, instead of filling up the internal reservoir. You could even put another ventilator to blow air under the floor boards.
Bob & Freddy Tuffnell
KeymasterHi Charles
I am not sure if hot and cold water system was on the option list from new. Perhaps on the very end of production.
Only advice could be to try to track where the tubes go, and check that there are no valves hidden to isolate part of the circuit. You could try to disconnect under the tap that doesn’t work, and see if it is not a blockage in the tap mechanism?Bob & Freddy Tuffnell
KeymasterThe stern gland, when at rest, after a couple of turns on the grease cup, should not leak at all.
Bob & Freddy Tuffnell
KeymasterHi Hamish
this information is available from the technical officer, article 145 and/or 146, as per procedure on the MOA website.
Otherwise, Jeckells sails are traditional suppliers for Macwesters, and they have all the plans. Member’s discount available.
All the best.
Bob Tuffnell
Bob & Freddy Tuffnell
KeymasterThat is a tricky one, Mike.
I think that I would first try to clean up the grease, and ( if you feel that it is safe to do so) , get a welding torch to heat up the remains of the studs, then quickly cool them with a jet of cold water. With a bit of luck that could break the “seal”, and enable you to unscrew them with a long-nosed Mole wrench.
Otherwise cut the studs back as near as possible to the casting, and drill out the rest of the thread of the stud. No need to re-tap, as you can use a bolt to hold the stuffing box in place.
If you do manage to unscrew the stud, T Norris Marine can supply the replacement stud and nuts assy.
Best of luck ?
Bob & Freddy Tuffnell
KeymasterHi Paul
Could I suggest that you start a new thread on the forum for the solar panels question, please.
Briefly, my opinion is that the MW27 already tends to be a bit stern-heavy, especially if you have a big Diesel engine ( the original specifications, and standard practice in the end of the ‘60’s for cruising boats was to fit a Stuart Turner 10 hp 2 stroke petrol engine, which weighed only about 50 kg.) .
Too much weight aft means that the transom will be partially immerged , creating a lot of drag to the detriment of sailing and motoring performance. Addition of a gantry for solar panels would aggravate that considerably.
Bob & Freddy Tuffnell
KeymasterSorry for the late reply.
pretty certain that it is 1 1/2” for the outlet, for 38mm inside diameter hose.
Its worth looking at ASAP Supplies to get good quality stuff at acceptable prices. I believe that they give discount to MOA members.
Bob & Freddy Tuffnell
KeymasterHi Michael
list to starboard? As I recall ( boat sold in 2019) my 27 had a slight list to starboard. I think that was due to the fuel tank ( usually kept full) and the original battery stowage which was in the starboard cockpit locker, with 2 x 110A/h .
I modified that by fitting one 75 A/h sealed battery under the aft end of the portside main cabin bunk, dedicated for engine starting, and the 2 x 110 A/h for the navigation and domestic circuits in the bottom of the central compartment under the fore cabin bunk. A pair of 35 sq. mm. cables came back to the 0/1/off/both switch next to the cabin entrance. That was sufficient for an emergency engine start in the event of the dedicated battery going down. That installation was particularly good when I fitted an electric windlass, as the supply cables were very short: full power available for lifting the anchor, as very little voltage loss, and no need for 12 metres of (horribly expensive) 70 sq. mm. cables back to the main batteries.Happy sailing for 2022
Bob.
Bob & Freddy Tuffnell
KeymasterI agree with Chris.
Don’t forget the option of reinforced plastic, alternative to DZ or bronze. (Marine quality bronze is so expensive that it’s not really an option!).After years of corrosion, there is virtually no way that you can unscrew the valve from the skin fitting, so simply get an angle grinder to work on the mushroom head of the outside. Go carefully, not letting it get too hot, and concentrate on the middle. Stop at the first sight of gelcoat. When you have a full circle of plastic visible, you can prise off the collar outside, and drive the threaded part inside the hull.
Bob & Freddy Tuffnell
KeymasterIs it a red hull?
Bob & Freddy Tuffnell
KeymasterThe two original fuel tanks were made of mild steel, painted red oxide, either side of the engine.
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