Tony Brooks

That is all perfectly normal, and it is to prevent the cold water in the calorifier expanding as it heats and eventually splitting the calorifier. If you also have an expansion vessel it would be, as you say, only operate in an emergency, like if the domestic water pump pressure switch stuck closed. Sorry about the Montego bloomer, despite you making it clear it is a Volvo, I got it into my head that is was Perkins MC42. No idea why. I can't see any hoses connected to the supposed lower section where the hoses connect or how/where it connects to the engine. I am not sure that external web is not just strengthening. I think that I would take one of the fittings off and probe to see if that chamber is split or not.

If the hoses in the second photo are the calorifier hoses then if they both go into the same space I am nor surprised you get no circulation and I doubt it ever worked. . Typically, in the absence of a suitably plumbed bypass thermostat, the feed to the calorifier comes from the cylinder head so with the engine thermostat closed the water pump will try to force coolant to the calorifier. The return connects to the input to the engine water, often T'd into the water pump hose. So you need to establish if the rectangular "box" the connectors screw into has one or two chambers - I suspect one. I also suspect that chamber comes after the engine thermostat, so you would not get any circulation with the thermostat closed (cold engine). Now a slight problem with the above. I think that may be a dieselised and marinised BMC Montego engine and from memory I think the Montego may have used a bypass thermostat so to work out what is going on and how to plumb it for a fast calorifier warm up. Although generally true, with modern engine water pumps I think they may be able to pump the coolant through the calorifier, but it would need a bleed point of the highest outlet, and only used when the engine was revving to purge any air, not ideal, but may work once bled. Where is it. I have never seen anything like that on an engine, and the PRV fitted to calorifier plumbing usually has a plastic cap, used to jump the valve up and down. What looks like a spring inside suggests it may, but the two things sticking out have a passing resemblance to 6mm blade connectors, except they seem to be curved, so no idea what they are.

I think the problem occurs when there is a voltage difference between the copper "earth" wire running from the shore supply or a neutral-earth bond on the boat/equipment and the soil and water close to the boat. That is likely to depend upon where the supply is actually grounded which could be at the bollard or close to the bollard or, is at a substation, a fair distance a way. I understand that it can also depend upon how close any high current commercial/industrial installations are to the shore bollard.

My view in addition to what Mike said. If you do earth it then there is a possibility that you could introduce hull corrosion, but as you do seem it be using it to power an extension lead with no earth connection to the boat hull this is very unlikely to impossible.

I suspect this is a case of best practice or possibly standards for sea boats being imposed on canal boats by surveyors, in other words bottom covering. I am fairly certain the 250mm rule is expected by the RCR/RCD. Following rules blindly with little common sense. Having seen photos of sheeted down fully laden working boats I ponder how they met the 10" freeboard rule.

And those who lived with DC supplies to houses have died of old age (mostly), so today the reports of "sticking" to faulty equipment has died with them.

Probably something like these, but I don't know the size of the holes. These are not split, so you would have to make one cut to get them around the cable. I just Googled "cable entry grommets"

Although I totally agree, the way examiners seem to interpret the regs to suit themselves would make me want to avoid an examiner trying to claim the box is metal or that plastic could cause a short. For a few pennies for grommets is not worth the worry. I have, I think without checking, loads that anyone can have a few if they collect from Reading, but for the cost not worth the effort.

If you do then use two ropes or one long rope with one end on the bow and the other end at the stern, the position yourself about 1/4 way back from the bow. I will describe using the two ropes. Run the stern line as far forward along the bank as you can and the bow line to the bank at 90 degrees to the bank if you can. Lean against/pull on the stern line and the boat will start moving forwards and also try sheer out, away from the bank. Use the bow line to pull the bow towards the bank or to stop it sheering away, keep the boat in line once it is well clear of the bank. The combination of tensions in either rope allows you to move it well away from the bank, moored boats, or to bring it back towards the bank. You will have to let all tension go when passing moored boats so you can flick the lines over the moored boats or board the boat and walk down the roof or outer gunwale.

Only if it chaffed through the insulation to metal OR a metal part of the connector that you said you pushed back in had touched metal, but if it has then that is a possibility. If that came from a Parsun specific website then it confirms we are dealing with a capacitor discharge system.

On can't second guess the rules a BSS inspector chooses to insist upon, be they BSS rules or his rules. I think that you could fit a rubber grommet that has been slit to get it around the red cable and into place. Then as long as the cable is supported less than 15mm below the housing i think it would more than comply with the BSS. You can get "blind" grommets that allow you to cut a suitable hole in them to better fit the cable. I would try that. You might be able to do that with the top entries as well by taking the switch down to fit them.

Unfortunately there are comparatively few canal boats with outboards, so I think business cards in marinas near you, and marina staff will be far more experienced with inboard diesels. You would probably find more experienced OB engineers below Burton on the Trent. The Parsun Power website tells you to contact them for a local dealer, and as the pin on their online map, plus no other details, seems to be in France I don't hold out much hope, but certainly contact them and see if they do have UK dealers who just might carry spares at "dealer" prices. I used to lift 9.9 HP outboards on and off the transom of out day boat fleet (Thames), so another option is to take the OB off and take it to a dealer or other OB non-dealer specialist. Ebay has one for £34 supposedly from in the UK with delivery between next Tuesday and Thursday. I could not quickly find a suitable one for £25 online. Again, not something I would normally suggest, but I think and coil of suitable size, mounting and with two plug leads and two thin wires attached stands a fair chance of working, even a motorcycle one. No more than that though - just a fair chance.

No personal experience but there are plenty of reports here that suggest as long as you talk to them, keep them informed, and don't take the micky they try to be helpful. Give them a ring and explain.

That is the ignition coil and without any further information I expect there is an electronic ignition setup under the flywheel or as a separate unit, it is even possible they are inside that coil assembly. As it is a four stroke I think there is one spark plug on each end of the ignition secondary coil, so both pugs fire at the same time, but one does nothing because it has no fuel in the cylinder. Called a lost spark system. If I am right then the other plug won't be getting a spark Because I have no details abut this particular system I am loth to suggest any further tests because if there is any sort of capacitor discharge used in the system and I don't know where that is you could wreck a multimeter by trying to check for voltage pulses in the two thin cables going into the top of the coil. However, I do know that type of coil on outboards has been known cause increasingly difficult starting, erratic running etc. that gradually gets worse until it won't start. Although it is far from best practice and in view of a lack of experience/detailed information, all I can suggest, with great reluctance, is that you change that coil if you can't find a local dealer or engineer. There is absolutely no guarantee that doing this will solve the problem, so it could be wasted money..

The manual suggested to me that the neutral and lanyard switch are on the steering "handle" by the throttle twist grip, but I agree they are often on the control. There are two, I think, control manual "buttons/switches" also on the control in addition to any levers. A plug socket is likely to have a rubber insert to make it harder to snap the plug or drop it overboard while working on it. It does not have to be the type used with a socket set, one with an attached T handle is likely to be suitable.