single
New member
Doing 200miles is fine, but check the oil is the correct spec.After about 18hrs non stop, when i put it into idle the oil pressure was hardly reading!Maybe give the engine a break every 6hrs or so?
Would my engine cope?
- Thread starter Tryweryn
- Start date
Doing 200miles is fine, but check the oil is the correct spec.After about 18hrs non stop, when i put it into idle the oil pressure was hardly reading!Maybe give the engine a break every 6hrs or so?
TQA
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It sounds like you are new to boats and boat diesels. If you are going offshore on a 200 mile passage and relying on the engine it is essential that you have spare fuel filters 3+ and can change the filter plus bleed the fuel system.
It is common for dirt in the bottom of the tank to be stirred up during a rough passage under motor and to block the filter
Also if you feel the performance under power is below expectations then check to see if the hull and prop are fouled by growth. In extreme cases a boat will barely move under full power and produce alarming amounts of black smoke.
It is common for dirt in the bottom of the tank to be stirred up during a rough passage under motor and to block the filter
Also if you feel the performance under power is below expectations then check to see if the hull and prop are fouled by growth. In extreme cases a boat will barely move under full power and produce alarming amounts of black smoke.
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LittleSister
Well-known member
The engine doesn't (or shouldn't) need a break. These engines, in industrial applictions, run generators for days on end.
William_H
Well-known member
Perhaps a little misleading in that the 6.5 knots is point on a graph of HP versus resultant hull speed where the graph starts to flatten out.Speed does not increase so much with HP increase. Of course more HP gives more speed but by the time you get to 6.5 knots a lot more HP gives only a small increase in speed this tendency getting worse at higher speeds. The effect is more noticebale on fat displacement hulls and less so on narrow catamaran hulls. The improvement is logarythmic with longer water line but ultimately unless you can get a hull to plane on top of the water only longer hull allows more speed.
Hence the old Queen Mary was built big for high speed. olewill
jwilson
Well-known member
18-20 hp is nowadays regarded as the about right power for a 30 ft sailing yacht. I don't know many who would expect much more power. Even if you put in 40 or even 100 hp the boat would not go much faster than with 20. I had a older similar size boat with 7 hp, and it was adequate, just.
scottie
Well-known member
Ideal for say a trip from Preston to Brighton!
john_morris_uk
Well-known member
I quite agree.
The 1.4 is a bit of a guess as the actual factor depends on various other bits of the design. (If you find that hard to understand think about how you could have a brick shaped floating object that would struggle to achieve 1.4* square root of the waterline length…) 1.4 is a useful starting point but some hull designs achieve a bigger factor and some less.
There isn't a magic point at which its impossible to make a boat go faster, but there is a knee on the curve of power vs speed where a lot more power doesn't make much difference to the speed. Where more power is helpful is when conditions are poor and wind and wave action slow the boat down. The extra power helps you keep closer to hull speed than the minimum power would have done. (That's assuming you can stand the slamming and sheer uncomfortableness of motoring hard into head wind and waves.)
stav
Member
If I was approaching this trip with an unknown engine, it would not be the engine I would be concerned about but he bits around it.
I would want to check the fluids.
Engine oil, water, gearbox oil.
Check the ancillaries; belt tension, bolts holding the alternator on, shaft coupling, stern gland, engine mount bolts etc.
Then on the trip check the oil after 3 to 4 hours. When the oil is hot it can be difficult to see on the dip stick so I touch the dip stick with a piece of kitchen roll and then the oil level soaks through.
Assuming you set out in calm weather I would run the engine hard for the first half hour or so to make sure the engine temperature was stable at higher loads so that if you have to punch in to rougher conditions later you know the engine can be pushed and if the temperature rises then you are still close to home to go back in and check it out.
Reading this through I guess that is not what you asked but hope it helps.
Hope you have a successful trip.
I would want to check the fluids.
Engine oil, water, gearbox oil.
Check the ancillaries; belt tension, bolts holding the alternator on, shaft coupling, stern gland, engine mount bolts etc.
Then on the trip check the oil after 3 to 4 hours. When the oil is hot it can be difficult to see on the dip stick so I touch the dip stick with a piece of kitchen roll and then the oil level soaks through.
Assuming you set out in calm weather I would run the engine hard for the first half hour or so to make sure the engine temperature was stable at higher loads so that if you have to punch in to rougher conditions later you know the engine can be pushed and if the temperature rises then you are still close to home to go back in and check it out.
Reading this through I guess that is not what you asked but hope it helps.
Hope you have a successful trip.
prv
Well-known member
Plus, as TQA alluded to, change the fuel filters before you set off (unless you have visible evidence they have been changed for you) and carry a stack of spares. Doing it yourself is preferable, as you will then know how.
Boats sitting awaiting sale are likely to build up sludge in their tanks, stirred up when they go to sea for the first time in months, blocking the filter and killing the engine. That and dodgy electrics seem to be the textbook delivery-trip problems (so also make sure you have a means of navigation independent of the boat's wiring, and a porta-power to independently start the engine wouldn't go amiss either if you have or can borrow one).
We had fuel problems on our delivery of Ariam, even though it was only a few miles round the corner from the Hamble to the Itchen. The broker was supposed to have arranged an engine service, but through miscommunication this hadn't actually been done (hence the "visible evidence" above). The engine started to die about halfway, and very disconcerting it was too, especially since the sails weren't rigged (I did get the anchor ready to drop). We were able to nurse her onto an outer pontoon at Ocean Village, and we did have spare filters with us (one of each type; on a longer trip you'd want more). The old one came out absolutely stuffed with black gunge.
Pete
sailorman
Well-known member
I hope you wind up with a good trip
ghostlymoron
Well-known member
Rather than rest the engine every few hours, my advice is to run at full throttle for a while every hour or so. This will alleviate 'bore polishing'.
Sandy
Well-known member
Not while the engine is being used
Lakesailor
New member
Not when the engine is hot and running. Short periods of idling are not harmful.
See this page from Cox Engineering http://coxengineering.sharepoint.com/Pages/Boreglazing.aspx
prv
Well-known member
I don't think bore polishing is the risk, but intuitively an occasional mini "Italian tuneup" feels like it could be good to blow out carbon from an engine being run relatively lightly.
Then again, as already mentioned, most modern boat engines were designed as industrial units to run generators, lorry freezers, etc for hours or days on end at a constant speed.
Pete
rob2
Active member
Just a summary really of all the comments so far... Once everything is running correctly, your engine should prove easily adequate and can be expected to run for as long as you wish. After a long lay-off even a relatively new engine may have a few problems, although they are usually associated with the ancillaries, fuel tank, exhaust and cooling flow. It would be a good idea to fit new filters and impeller and carry spares now you're sure you've sourced the ones that fit! Keep an eye on the cooling water through the exhaust and if you have them, the temperature and oil pressure guages. Afew shake-down runs of increasing length and you'll have proved everything is working correctly or have fixed it along the way.
When I bought my boat, with a much older engine, it had just been "serviced". It started and ran fine for about half an hour, then the fuel pipes which had softened beneath the clamps sucked in air and she stopped. We sailed most of the day before one of the crew discovered why and cut the deteriorated ends off and she's been fine ever since.
The engine could run continuously for its lifetime, but the ancillaries needed to marinise it are subject to problems not found on a building site generator - fuel bug, weed blocking the coolant intake, etc.
Rob.
When I bought my boat, with a much older engine, it had just been "serviced". It started and ran fine for about half an hour, then the fuel pipes which had softened beneath the clamps sucked in air and she stopped. We sailed most of the day before one of the crew discovered why and cut the deteriorated ends off and she's been fine ever since.
The engine could run continuously for its lifetime, but the ancillaries needed to marinise it are subject to problems not found on a building site generator - fuel bug, weed blocking the coolant intake, etc.
Rob.
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TonyBuckley
New member
My surveyor said to run for several hours tied up in the marina in gear at about 2500 revs. Stressed the lines and no doubt the cleats and pontoon but it made me feel comfortable that it run and performed well.
Ruffles
Active member
I like to run the engine for a long time after changing filters. And at a decent load. The only time I've had engine embarrassment was a poorly seated seal after a filter change.
Actually I find checking the fuel by taking a sample from the bottom of the tank is more reassuring than new filters.
Tryweryn
New member
Top advice. From the above I have made a spare list and having the engine fully serviced. I phoned Beta and they say the engine will take me all around the country if i wish lol. (Well they would say that). They were very helpful. At present reading up on the engine and trouble shooting.
The ship has a integrated marine system with two plotters, radar, AIS, GPS etc plus other instrumental aids. I also have a new Garmin Echo 50s that operates independent of the marine network and wi-fi. This has BlueChart® g2. If all that fails I have a chart and compass lol I would rather be over prepared I think. I'll take loads of extra fuel and mark refill points. I'll check but consumption I think is about 1.5lt per hour.
I'll probably use the sails when I get out there. But I'm covering every base. Murpheys law and all that lol
The ship has a integrated marine system with two plotters, radar, AIS, GPS etc plus other instrumental aids. I also have a new Garmin Echo 50s that operates independent of the marine network and wi-fi. This has BlueChart® g2. If all that fails I have a chart and compass lol I would rather be over prepared I think. I'll take loads of extra fuel and mark refill points. I'll check but consumption I think is about 1.5lt per hour.
I'll probably use the sails when I get out there. But I'm covering every base. Murpheys law and all that lol
Tryweryn
New member
I hope you guys still get such an adrenalin rush after sailing for years lol Exciting stuff.
TonyBuckley
New member
That is exactly the opposite reason I go sailing lol. I get enough adrenalin through the week and prefer contemplative calmness. Sometimes I succeed