@duncan-mckenzie
Forum Replies Created
-
Posts
-
In regard to Voltair’s post above about getting it in the eye, and breather heights, that sounds feasible. But what about the breather on the port side deck on the outside coaming adjacent to the main tank filler plug, if you overfill the main tank it bubbles and flows out of there onto the deck before it overflows from the filler neck itself. Is that not therefore the main tank’s breather ( which is then higher than the wing tank)? Anyway, it sounds like important to use any wing tank with great care.
Dear Margriet and Erik,
I am interested in this subject as I will be ocean crossing later this year and so far have only the crew or the NECO autopilot hardware modernised through a SIMRAD control box AP22 brain. It works quite well until the seas get heavier , especially downwind.
Someone locally is offering a second hand Aries for not much money. However I am not so keen on the control lines idea so the idea of using the emergency steering is very attractive. However, if you have ever experimented with using the emergency steering you will find that it takes enormous force to turn the tiller, since there is no gearing between you and the rudder itself. It is really surprising, literally you against the force of the water, direct. In that sense it really is, perhaps, just for emergencies.
I can imagine it might be problematic as a connection point, though I am not an engineer and possibly some kind of gearing system could be superimposed onto the aft deck above it, to facilitate?
I wonder if you have asked Windpilot what they think of your emergency steering idea, I am sure they would have a view?
Also as an aside, I wonder how far, with the right balance of sails, one can use the mizzen sail as a crude wind steering device? I have heard that with a long keel and a mizzen sail, quite a lot can be done. This is something I plan to experiment with as soon as I can get back on the water, but am interested in the experience of others.
Best regards,
Duncan
I could only add that a German boat builder I met was very enthusiastic about Windpilot, and said he had ‘tested it’ in Force 9 in the Atlantic over a 4 day gale.
I have exactly the same question as Adrian above. I presume they are adhesived onto the deck and need cutting free and then rebounding with marine sealant. No sign of any screws accessible from above or below. Any useful info from other owners please respond. Cheers Duncan
Good job, Ollie! All very interesting and telling.Thanks for sharing. Greetings from Pollenca, Mallorca.
I should add that this was also a problem with a previous 60 m length of chain that came with the boat, but which I replaced due to age.
Hi Ollie,
Having filled 235 holes from the past two or three teak decks’ screws at different times on Czarina Ue, using sealant and textured fibreglaas squares in order to seal with water penetration, I’m sure our decks will come off in the next five years to properly remedy the problem from above. So I’m interested to know the cost and factors involved though I might be tempted to go for a cream grip paint instead if it’s cooler for the interior. I saw that on a similar ages boat recently and it looked very nice, the sMe vibe as teak in a way.
Anyway I’m all ears!
Regards to you all,
Duncan
Having understood that the main gearbox level should be checked from cold or with the engine off for a significant amount of time, despite what both the Perkins manual and the Thameswaysmusl say (!) I Havd managed to remedy what we thought was a worn clutch on our Thamesway 12000 Mkt 2. We are now motoring again without a hitch so I think we’ve escaped the dreaded ‘gearbox out’ for now.
The pressure gauge which on my boat gives a read light on the dashboard by the wheel only on starting or if there is low pressure in the gearbox due to lack of oil. The gauge is not, as I understand it from Thamesway,a switch. It doesn’t need to be a switch because the way the gearbox works is that if the pressure gets low enough the clutch can’t grip the shaft and turn it, due to la k of pressure-induced friction, so the outcome is the same.
From the Type 12000 Mk2 Manual: page six
“An oil pressure gauge is provided as an extra to indicate the oil pressure in the hydraulic system…(pressure figures)…the pressures read by the gauge are not critical but, should the oil pressures fall appreciably below these figures, insufficient pressure may be exerted by the Operating Piston to prevent the cone clutches from slipping. This will not only result in loss of power at the propeller shaft but will also accelerate clutch lining wear.”So if you have a slipping clutch for goodness sake check your main gearbox oil level which should be not higher than the mark on the dipstick ( though Kevin at TMP said it could be as much as 1 cm above the mark but really not more). If this is definitely at the correct level then you may indeed have excessive clutch wear.’ A full service with TMP is currently approx £700 plus vat, not including couriers fees.one week turn around at their end.
Cheers, with much relief!
FYI Kevin says that pressure gauge is only a warning light of the pressure status and has no power to disengage or control the clutch.
I’m sure there was sufficient oil in the gearbox dump so I’m going to have to bite the bullet I think.
Regards, Duncan
Thanks Marilyn, that’s an interesting point, and a mechanic was fiddling with the gearbox pressure gauge recently as part of diagnosing a faulty alternator when he was trying to understand what the light on the dashboard did ( he expected it to go out once the alternator started charging, though I explained to him it was a gearbox oil pressure light. I hadn’t however realised it was a switch that controlled clutch engagement. I believe that I’ve kept the oil level high enough in the main gearbox, and I’m surprised Kevin at TMP didn’t mention it this morning I will mention this to the mechanic and to Thamesway tomorrow to see what they say. Thanks again for your advice. Duncan
I have recently suffered intermittent loss of forwards propulsion simultaneous with the Perkins 4108 hunting up 100 revs. This cycle occurs about once a minute for 15 secs, and I see my hull speed drop off during the higher revs. The prop shaft is still turning during that time but I imagine that is from the force of flow over the prop blades?
Spoke to Kevin from THamesway Marine this morning and he says the bearing will be worn and the Gearbix a Thamesway 12000, probably a Mark II, will need to come out and be overhauled. This will cost around £1200 inc VAT and parts, with the courier charges on top, and it’s a heavy item.
Unfortunately I am in Sicily, in Siracusa, and not expecting this (!) I am now looking for a mechanic / engineer to help with this. I understand from the forum that this may be possible with the boat in the water, as Voltair and Trevor have managed it in the past.
Just wondering if this box is worth overhauling bearing in mind its age and the difficulty of getting parts apart from via the UK, or there is any advantage in considering a more modern adaptation? From the forum it sounds as if people have stuck with the old box, and just renovated it.
Any further advice on its removal and or replacement with more modern versions, I would much appreciate.
Thanks,
Duncan
This has potentially saved me a lot of grief thank you! By the way do you use white waterproof grease or regular grease when filling the tap? Thanks. duncan
This from Kevin O’Bryan of Thamesway Engineering today:
“The neutral brake only works when the engine is running.
The prop rotation when sailing will not damage the gearbox. If the noise is annoying you can lock the coupling as long as you remember to unlock it before starting the engine again.”So take your pick, I guess!
My shaft is slightly loose so I’m keen to lose the rattling when under sail.
Cheers
Thanks Peter. I guessed it could be the reduction gear box 2:1 that stops reverse engaging,possibly that there is no oil pressure when the engine is off so that the clutch doesn’t allow engagement of gear?
I have now read in the Perkins Marine Service handbook:
P65:
“On the Nicor TMP 12000 gearboxes it is necessary to run the engine after trailing the propeller for 12 hours to lubricate the gearbox.
…Transmissions operating reduction gear must have means of stopping the transmission output shaft from prolonged or continuous freewheeling. This is because the engine, being stopped, does not drive the oil pump in the gearbox. The box therefore is not being properly lubricated.”So once again a case of RTFM !
But still thanks very much for your input. You may of course not have a reduction gearbox, but I know I do.
Thanks again
Duncan
Thanks Peter. So far I could only guess that it might be the reduction gear box that stops reverse engaging,or possibly that there is no oil pressure when the engine is off so that the clutch doesn’t allow engagement of gear? I’m not a mechano-technical person so really not sure, but thanks very much for your input.
Duncan
Brilliant Roger, I will hunt it out when I’m back on board on Thursday, hopefully it will be the same for mine, no 110. Thanks.Duncan
Thanks Van,
That is helpful. I am negotiating to have one made at the moment, and there is a choice of 1.5, 2.2oz spinnaker type nylon or a light Dacron ( the original spec I think). I thought perhaps the light Dacron might be more in keeping with the other three sails and allow a few more knots of wind to be harnessed? Any thoughts on that?I am now the proud owner of Czarina Blue hull no 110, built 1973, carefully looked after by the previous owner Mike Bennett. Currently moored in Aegina, Greece, I look forward to getting to know her better.
