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Can’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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Hi 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.
As 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.
Hi 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?Hi 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
That 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 ?
Hi 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.
Sorry 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.
Hi 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.
I 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.
Black Magic was the star of the Macwester stand at the Amsterdam boat show, when new. Philip Hamers was the importer/sales agent for the Netherlands. Can’t remember if he kept the boat for himself, or sold on to a customer.
I will have a look in my old photos, see if I can find anything.
Did he say just the seacock ( valve) or was he saying that the skin fitting ( the kind of giant hollow bolt that is clamped to the hull), should be checked as well ?
What material are they ? Brass, plastic? Any chance of a photo.As a general rule, I would advise that you have the boat ashore to do that. After years of service, the chance of getting the different parts unscrewed without any issues is pretty slim. Almost inevitably the only answer is to use an angle grinder to carefully remove the head of the skin fitting on the outside, and remove the old assembly from the inside.
Even trying to do that on a tide, with the boat drying out on the hard can be pretty stressful, especially for the engine inlet which is very low down, so you don’t have much time to work on it, unless you are in Jersey with more than 10 metres of tide range.
