Tony Brooks

There is often no logic in what previous owners have done. The basic fact s that as soon as these pumps suck a little bit of air, they stop pumping, so that can only makes tings worse. Demount it from the can, and it will probably do as well as any other pump of this type.

Providing you get them properly hot and run them under the highest load you can, but not in gear unless you are cruising, so maybe the alternator load at around 1200 to 1500 rpm for a non-vintage diesel while tied up. Running on no load and only for a few minutes is likely to do more harm than good.

The photo provided seems to show the pump mounted on top of some kind of rectangular tin. If this is so, then it will hold the pump even further above the baseplate, so even less water will be sucked out, leaving more in the boat. The pumps normally have their own strainers mounded into the base of the body, so I would have thought such a can is unnecessary.

So how deep was it/under at the pump.

What is "ponded water"? I do not recognise the term How deep was it? If it was, say, over 20mm it should have pumped down to about 6 to 10mm, if less then I am not surprised it did not clear the water.

Have you tried tightening the gland packing a little, it may have dried out. Do not tighten t so much you can't turn the coupling by hand 1. Ensure that when you slide the shaft half coupling back onto the gearbox half coupling, the two slide together without the land on one half binding on the recess on the other half. If they do bind, you need to slacken the mounting nuts and either slide the engine on the beds or shim both mounts at the appropriate end of the motor 2. Now ensure the two half couplings are together but if the alignment is out there will be a gap between the two somewhere, so again, depending upon where the gap is, slide the engine about or add/remove shims from both mounts at the appropriate end. You gave the maximum gap acceptable in a previous post. Tighten the engine down and recheck See http://www.tb-training.co.uk/10sgear.htm#bmn33

I think the majority, if not all, easily available bilge pumps are centrifugal pumps and as such they will not totally drain the bilge, always leaving a small amount of water behind. Even if it is set down in a recess, it will still leave water in the recess. So if there is not much water in the bilge the pump may be fine, but I would invert it and see if you can see the impeller which may be clogged, that would stop it pumping. It is also fairly normal for the last "pipe full" of water to drain back into the bilge when the pump is turned off. A non-return valve close to the pump would go a long way to prevent this BUT bilges are not the cleanest of things so such a valve may clog & reduce/prevent pumping, or just jamb open, so the water still drains back. Without more info, I am not convinced anything is wrong with your system because it sounds pretty normal to me. If you fitted something with a rubber impeller, like a Jabsco Water Puppy (horribly expensive) the impeller would retain the water in the pipe until the impeller broke or wore, so it is not really a solution.

Maybe, but fitting a more shapely one is one step further away from a true replica, so might start to cause RCR problems with the sort of engine I understand is to be fitted. I don't for a moment think that is why an original is wanted, though.

I don't know why. As far as I know, right back from Thames Conservancy days launch licences were based on length and beam.

I think there is also a technique, like pushing one side under the lip and then using a tool to push the other one under.

except the OP has not told us if this is an all-in-one bilge boat, but it probably is not likely because if it was so the water would have been pumped out. I suspect the OP does not know much about narrowboat design and its implications.

Except water will contiue to drain back for several days/weeks even if there is no leak from the domestic water system.

So it is not a seal, but a cover strip. You may find it easier if you put the seal in very hot water to soften it. The tool often used on each side is called a Herzim trim fitting tool, with a metal wheel at one end to push the trim under each lip. On no account stretch the trim as you fit it, if anything try to compress it, if you stretch it, it will do exactly what yours has done, but they do shrink with age so you may want to either leave the resultant gap at the bottom or fit a small infill piece I always did OK with a small flat bladed screwdriver.

So what type of gauges, if they are for petrol engines they won't work because it is uses pulses from the ignition coil LT circuit. If you have the fly lead on the correct place then with a DVM connected between the fly lead and negative/alternator case with the DVM set to frequency (Hz) you should find the frequency goes up and down as the speed is increased and decreased. Alternatively, with the DVM set to AC volts it should also go up and down with speed, but I can't give you any values. I suspect with the DVM set to DC volts, the reading will also alter with speed, but I have never done it. Have you powered the rev counter ( + & - ) as well as connecting the fly lead to it? If that does not happen, try it between the alternator main output (B+) and the fly lead. If that works, then I think that you have fly lead on a negative rather than positive diode.

FWIW, the body of the thing seems well outside the cylinder head and I think that I can see the glow plugS wiring below the injectors, so four glow plugs, not 1. A glow plug will also have at least one wiring connection and will have one end inside the cylinder head or air in take. I can't see any sign of such wiring in the vicinity (hence me wanting to see what is underneath the thing).

That water may have been there for many, many months or years if no one ever checking it, and if there was no obvious trap in the floor or if it was covered in flooring the surveyor may not have felt able to check it. Likewise, the people who did the hull would have no reason to look under the floor. The bilge pump (singular) is usually behind the back bulkhead and in most boats the under cabin bilge is sealed by the bulkhead, so the water can't drain back to the bilge pump. Be aware that water is likely to drain back over the next few weeks, so check it every day or so and expect it. do not worry unless it does not reduce in volume over a month or so. If it has been there for ages, and you are sure it is not related to the domestic water system, then it is likely to be a gradual build up over the years, from leaks between window frames and cabin side, roof vents and roof, and simple condensation. It is unlikely to cause the boat to sink in the short term and if its a 8mm or 10mm baseplate is unlikely to sink it for many, many years as long as you keep the bilge as dry as possible.

Quick answer is not me because I can't see what is underneath it. We need an Isuzu engine owner or someone with good experience of them Have you asked Engines Plus who (I think) used to be the main mariniser. https://www.enginesplus.co.uk/ Just a thought, could this be the hole for an "extended dipstick" as opposed to a much shorter one typically found on industrial engines.

Thanks. looking at that photo, I can only see a lip on the periphery of the larger diameter flat. In that case, I can't see what would retain it and expect it to be glued in place, probably by a contact adhesive. I think we still need photo(s), possibly annotated to explain what we are looking at.