TeamElla

Can I join in? (Something to do with a finger pontoon, missed footing and a boat left in gear (pulling back out of the berth)...

Since I don't use it, I've never noticed the lack of riverside petrol re-fuelling facilites on the Broads. It should be noted that for obvious reasons, most (if not all) marinas on the Broads prohibit re-fuelling at the berth in their terms and conditions, which require the signature of compliance of all berth holders. It doesn't stop these rules being flouted regularly in our marina and the above would seem to explain why. For the sake of our resident wildfowl alone (not to mention the mess that it makes), I dread the consequences of a spill.

As everybody who has actually been to Norwich Yacht Station knows, the security gate there is selectively targeted at 90 year old vandals with bad knees. If that requires an explanation, see pic.....

Thanks Griff It’s thanks all round really with Vaughan posting the original introduction to plummer blocks, followed by your pic (which set the seed of an idea) and finally to Horning Pleasurecraft for carrying out the actual fabrication and fitting of the custom bracket. I’m just glad that I got the measurements right! p.s. if Simon is reading this, I will give the bracket drawings and details of the plummer block (as used) to any centre cockpit JGM Madeira owners that ask for them. Rgds, Steve

End Game (see pic) Cheers, be seeing you, goodnight...

Well that blows my chart out of the water (for those that remember it). I have been thinking for some time that there is a about a 3 inch discrepancy on all entries (chart showing 3 inch greater clearance than actual at the bridge). Don't know where that error crept in Next issue will be checked first...

I tried to edit the last post and was too late, so here it is again:- I've just seen the above, which has a max output rating of 5 amps and can cope with batteries being on charge. Whether it would bother sensitive electronics would depend on how good it's output filtering is (as it's bound to be a switch mode converter which are of a type that can also sometimes be responsible for interference on the radio).

https://uk.rs-online.com/web/p/isolated-dc-dc-converters/0183837/

most of the cigar socket USB chargers don't go above 2.5 amps output

Of course that's true (but a really cheap quasi sine wave inverter doesn't need to be loaded up to put out a poor copy of a sine wave AC feed) With inverters, we have only been discussing operating or charging equipment from an inverter's AC output. USB voltage is 5 volts DC, so it's a pretty simple circuit to produce a regulated 5 volts DC output from a 12 volts DC input. Cigar socket USB adaptors come to mind.

"Higher power inverters naturally use more expensive components that are physically larger, need big heatsinks and different board layouts, track thickness, track spacing etc to handle their rated maximum output loads. These all include at least one cooling fan and must be fitted in a cool area with sufficient space around them to allow proper circulation of air for cooling" Let's not even get into how much they draw from your batteries. Don't even think about using one for heating. We find our modest 350 watt unit to be a good compromise.

They do Andy, but I don't know how the supplied 61w USB C Power Adapter (that plugs into AC mains) would fare on a quazi sine wave inverter's output. I wouldn't take the risk, but anyone doing so should unplug it quickly if it starts to get hot. Rgds, Steve

Many will appreciate that domestic AC mains electricity delivered to your house is pure sine wave. With all DC to AC inverters, it would be easy to produce a square wave output from the DC input supply. The difficulty comes in shaping that output to either approximate a sine wave output (quazi sine wave inverters) or with much more signal processing / output filtering, to achieve a clean sine wave output (true pure sine wave inverters). Square waves produce nasty harmonics that are a death sentence to the switch mode power supplies found in most consumer electronics these days and quazi sine wave inverters still have some square wave content in their output. The more power you are drawing, the worse it gets. So the big difference in price between the two types is no surprise and even the cheaper quazi sine wave inverters vary in the quality of their output. I wouldn't touch them with a bargepole. Higher power inverters naturally use more expensive components that are physically larger, need big heatsinks and different board layouts, track thickness, track spacing etc to handle their rated maximum output loads. These all include at least one cooling fan and must be fitted in a cool area with sufficient space around them to allow proper circulation of air for cooling.

I cannot, and will not, ever start every sentence with the expression "so" https://www.merriam-webster.com/dictionary/so what what what Now about these tide tables:- We just download a week's figures from shorebase (together with the handy shading that shows which areas each tide time covers)

Who is marketing these moorings. Does anyone here know?

Again to clarify:- Our PSS Seal never leaks (even during the prop shaft waggle). These seals always have river water within their vent tube up to the boat’s water line. Both our’s and Simon’s vent tube run right up to the top of the engine compartment and that’s where the water has been emerging. Weirdest thing to watch and I have the video to prove it. On a fast boat (at above 12 knots) it is necessary to pump water down this tube to lubricate the PSS seal as the water drains outs of the shaft log / stern tube at greater speeds. On displacement boats like ours there’s no need for all that malarkey. Re our prop shaft:- I am not aware of it moving fore and aft at all under way (forward or astern) For those that are not familiar with PSS Seals:- The rubber gaiter clamps onto the shaft log / stern tube and has a mobile graphite sealing block on the other (forward) end of the gaiter which bears against a machined stainless steel mating ring that is clamped onto the prop shaft. This ring has an “o” ring seal to the prop shaft and it is slid backwards to compress the rubber gaiter a set amount to maintain the graphite/metal rotating seal. When it’s first fitted, the graphite/metal seal needs to be run in for about an hour to stop it dripping and leave you with a bone dry bilge from then on (unless water’s coming in from somewhere else).

Hi Grendel, Thanks for that but no it’s the other way around. Gaiter compression is higher when going astern. Rgds, Steve

I should clarify that. Water only comes out when the waggle is causing the prop shaft to hit the shaft log. Directly on cue it comes pouring out during the banging (and I do mean pour, it’s no trickle). Astern it always happens.

https://store.pyiinc.com/products/hy-vent

I don’t think that the “waggle” would be a problem if our prop shaft was sitting bang in the centre of the shaft log, but the PSS Shaft Seal will certainly appreciate not being waggled about. Another revelation:- During the waggle, water comes pouring out the end of the tube on the PSS Seal’s air vent (It seems to act like a pump!) This seems to happen on all PSS Seals when you’re going astern and I’ve wondered for months where the small amount of water in my engine compartment bilge was coming from. PYI have now produced a special valve to put on the end of your vent tube that shuts when water reaches it. It’s called something like “hy vent” Link will follow when I find it....

“which sits in the right position at rest” At least I hope so. That’s in the hands of the yard fitters. We can’t do anything about the shaft sitting high in the shaft log without taking it out and refitting it and THAT’S NOT GOING TO HAPPEN. (I’m done with removing it, refitting it and glassing it back in again). Re using the meter to check continuity:- You’re right Simon but resistance through the water will be very high. Using the buzzer is your best option to check for actual contact. Apart from the actual resistance readout, it needs a little extra current to flow (albeit very small) to sound the buzzer.

Hot off the press - our new mountings -see pic (since I’m sitting on board adjacent to Clive’s hire base). Stage 2 is in progress (see 2nd pic) as with our tight tolerances in the repaired shaft log we cannot allow the prop shaft to waggle about on tickover. The increased mobility in the rubber mountings (as opposed to engine sitting flat down on metalwork) is now causing the prop shaft to bang on the side of the shaft log, both at tickover and again at 800 RPM. It’s easy to stop it with light finger pressure, so enter the new Plummer Block with a plain bearing just to act as a guide for the shaft (which sits in the right position at rest). I’ve just drawn up the details of the support brackets required including some allowance for adjustment of Plummer block position up/down/left/right and delivered them to the yard. Watch this space...........

Yes that’s them

The problem with the old aft mountings on our BMC1500’s is finding someone who has any (as they are now out of production and officially obsolete). Clive thinks that they used to be called “Tempest Isolators”

Hello Simon, I’ll tackle most things but lifting engines is out of the question, so marine engineers are doing the work. As far as I know, all the shims have been removed now. They had been added temporarily to prop up the engine until new rubber mountings could be fitted. Sorry but I never did see exactly where they were added at the aft mountings. The engine is now lifted back up to where it should be. I reckon that (if you still have your original “stuffing box” type shaft seal), your shaft log will most likely have escaped damage due to the stuffing preventing metal to metal contact. to be continued....