johnphilip
Well-known member
The Bukh ran fine but we were losing confidence due to its age, so we changed boats.
What did you replace your Bukh DV20 with?
- Thread starter snooks
- Start date
stav
Member
I have not replaced an engine yet but interested in the comments but from the perspective of someone who buys older boats and tries to keep them going.
Firstly what about this, but suspect it looks a lot bette rthan it is.....
http://www.ebay.co.uk/itm/Yanmar-3G...at_Engines_EngineParts_SM&hash=item43acb67727
http://www.ebay.co.uk/itm/Bukh-Dv20...at_Engines_EngineParts_SM&hash=item27c2b28eb0
Or how about these
http://www.ebay.co.uk/itm/27-80hp-d...at_Engines_EngineParts_SM&hash=item2ea6d8c454
Must say when I look at a second hand boat I would rather it had an old merc, bukh, or yanmar, if it has an old (over 10/15 years) beta, vetus or nanni I would buy the boat with one of the previous three as I stand a hance of keeping them going unless the price allowed me to reengine. Obviously just personal prejudice.
Firstly what about this, but suspect it looks a lot bette rthan it is.....
http://www.ebay.co.uk/itm/Yanmar-3G...at_Engines_EngineParts_SM&hash=item43acb67727
http://www.ebay.co.uk/itm/Bukh-Dv20...at_Engines_EngineParts_SM&hash=item27c2b28eb0
Or how about these
http://www.ebay.co.uk/itm/27-80hp-d...at_Engines_EngineParts_SM&hash=item2ea6d8c454
Must say when I look at a second hand boat I would rather it had an old merc, bukh, or yanmar, if it has an old (over 10/15 years) beta, vetus or nanni I would buy the boat with one of the previous three as I stand a hance of keeping them going unless the price allowed me to reengine. Obviously just personal prejudice.
snooks
Active member
I had a good long chat with Scott from TS Marine today. He's done a number of sadler 32s and there are no issues of space. He recommended the 30 as it has greater torque than the 25, it will also be operating at less revs which would give better performance at lower revs, which would also make it quieter at cruising speed. He was honest when he said there would be few times when we would actually use all the engine's power, but when we do need the power to punch against the tide or make a tidal gate, or arrive before it gets dark, etc. then the power will be there. Also if we're going to all this expense for a few hundred pounds more it makes sense.
Tranona
Well-known member
With all due respect to your proposed supplier, overpowering a boat in this way is not necessarily a good thing. The engines are designed to run at high revs and there is no benefit apart arguably of less noise to run at low revs. You still use the same amount of fuel as you are drawing the same HP from the engine. A significant downside of overpowering is difficulty in keeping speed down when manouevering at low speed. The prop you will have to fit to absorb the unnecessary power is likely to lead to excessive thrust at low speed. Your boat will achieve its maximum hull speed easily with only 20HP - a 50% increase is wasted.
A well matched boat/engine/prop combination will achieve maximum hull speed at close to maximum revs and cruise sensibly at around 65-70% max HP with the final HP available for adverse conditions. Know it sounds good - whats an extra few hundred pounds and there is space - but the money is perhaps better spent on a good prop and replacing the whole drive train rather than just putting in the biggest engine that will fit.
A well matched boat/engine/prop combination will achieve maximum hull speed at close to maximum revs and cruise sensibly at around 65-70% max HP with the final HP available for adverse conditions. Know it sounds good - whats an extra few hundred pounds and there is space - but the money is perhaps better spent on a good prop and replacing the whole drive train rather than just putting in the biggest engine that will fit.
snooks
Active member
It all goes back to torque apparently. The torque of the 30hp is a closer match to the dv20 than the 25 hp is. If I was replacing any other 20hp engine than a Bukh, I could have had the 25hp and feel I was gaining.
All the stern gear will have to be changed anyway as my props shaft will be too short....unless I want the engine under the cockpit.
The other advantages are I won't have to remotely mount the sump pump, and I can get a 100A alternator.
With the 30hp and a 65A alternator it works out at about £240 inc vat more than the 25hp with a 70A alternator.
I could get a bigger engine in there, but that would be really silly
All the stern gear will have to be changed anyway as my props shaft will be too short....unless I want the engine under the cockpit.
The other advantages are I won't have to remotely mount the sump pump, and I can get a 100A alternator.
With the 30hp and a 65A alternator it works out at about £240 inc vat more than the 25hp with a 70A alternator.
I could get a bigger engine in there, but that would be really silly
Tranona
Well-known member
Don't want to get into an argument, but torque is relatively unimportant on a sailboat auxilliary (or rather the minor differences between engines is). The maximum torque on the 25 is actually the same virtually as the Bukh, but over a narrower range. It is however in the operating range of the engine. Torque is of value in other applications where a wider range of engine revs is used - for example on a workboat, or at the other end on a high power motor designed for a planing craft.
Pretty sure the Bukh was not chosen for your boat originally because of its torque - it was chosen because it was arguably the best 20HP engine available at the time. You will never be able to use even 25hp on your boat anyway because it simply won't go fast enough to need it. You are already increasing power by 25% over your original which would not have been considered underpowered in its day.
Much the same argument can be applied to the alternator question. It is more the size and pattern of usage of your battery bank that determines the capacity of your alternator - but this is a debate for another day. As you know when that subject comes up, the threads get as long - if not longer than ones on replacement engines, but not as long as anchors as there is some good science behind the electrical arguments!
Pretty sure the Bukh was not chosen for your boat originally because of its torque - it was chosen because it was arguably the best 20HP engine available at the time. You will never be able to use even 25hp on your boat anyway because it simply won't go fast enough to need it. You are already increasing power by 25% over your original which would not have been considered underpowered in its day.
Much the same argument can be applied to the alternator question. It is more the size and pattern of usage of your battery bank that determines the capacity of your alternator - but this is a debate for another day. As you know when that subject comes up, the threads get as long - if not longer than ones on replacement engines, but not as long as anchors as there is some good science behind the electrical arguments!
snooks
Active member
Back in the 80s the average length of boats was smaller and marinas were bigger, now when we go to marinas they stick us in tight berths where being able to give the boat a good quick shove in the right direction quickly can avert all sorts of manouvering fun - especially with a skeg and an offset prop. So having torque in the lower revs is a benefit, as the turning force is greater, so the prop will get to the required revs faster. Yes I could avoid marinas, but next year we'll be cruising with our newborn, so I can see weekends in marinas becoming attractive if only to get out of the range of my daughters screams or a quick nappy dash!!
There are times when I have felt that the 20hp is underpowered, for example, motoring into a head sea, coming into Portsmouth on a spring ebb, or getting past Cowes into Osbourne on the again at the height of the ebb....of course if we had more time this wouldn't be a problem, we could do the same thing a couple of hours later, but time isn't something we have a lot off at the weekends especially when it's a 2.5 hours drive to the boat. I know I should fight nature, but there are time when doing so makes life easier and the misery shorter
And yes I do know that for that extra knot I'll be burning a lot more diesel but I'll be burning it for less time
I'm fully aware that I will rarely make use of the extra 5hp, and I hope I don't have to, but not spending £200 and getting the extra power it will afford me seems like an opportunity missed. I've spent far more on safety equipment that I haven't used, and it just sits there going out of date, at least if I really want to use this money, I can
Not everyone uses the power in there cars, after all you could put a 1000cc engine in a Ferrari and you would still get where you're going, but having more power gives the owner more oomph if they need it. Compare a 2 litre diesel car with a 1.6, you don't need that extra power going down the motorway but as I said above if the bigger engine will be doing so at less revs and a lower noise level.
Many years ago the engine was only used to get in and out of a berth, partly because they were big, heavy and underpowere...technology has improved, as the way we sail has changed. This last year we have had very little wind and our yacht has been more like a motorboat with a mast, because even with no wind we still like to go somewhere.
Also back in the 80s a boat full of electronics consisted of a LCD instruments VHF and Decca, maybe if a radar, now my chart plotter alone probably uses more power than all those put together, not to mention iPhone/iPad charging. Pixie was ma in the year regan announced GPS would be made available to everyone, seatbelts became mandatory and Austrailia II won the Auld mug. We have 2x110Ah domestic batteries and a separate engine battery now.
There are times when I have felt that the 20hp is underpowered, for example, motoring into a head sea, coming into Portsmouth on a spring ebb, or getting past Cowes into Osbourne on the again at the height of the ebb....of course if we had more time this wouldn't be a problem, we could do the same thing a couple of hours later, but time isn't something we have a lot off at the weekends especially when it's a 2.5 hours drive to the boat. I know I should fight nature, but there are time when doing so makes life easier and the misery shorter
And yes I do know that for that extra knot I'll be burning a lot more diesel but I'll be burning it for less time
I'm fully aware that I will rarely make use of the extra 5hp, and I hope I don't have to, but not spending £200 and getting the extra power it will afford me seems like an opportunity missed. I've spent far more on safety equipment that I haven't used, and it just sits there going out of date, at least if I really want to use this money, I can
Not everyone uses the power in there cars, after all you could put a 1000cc engine in a Ferrari and you would still get where you're going, but having more power gives the owner more oomph if they need it. Compare a 2 litre diesel car with a 1.6, you don't need that extra power going down the motorway but as I said above if the bigger engine will be doing so at less revs and a lower noise level.
Many years ago the engine was only used to get in and out of a berth, partly because they were big, heavy and underpowere...technology has improved, as the way we sail has changed. This last year we have had very little wind and our yacht has been more like a motorboat with a mast, because even with no wind we still like to go somewhere.
Also back in the 80s a boat full of electronics consisted of a LCD instruments VHF and Decca, maybe if a radar, now my chart plotter alone probably uses more power than all those put together, not to mention iPhone/iPad charging. Pixie was ma in the year regan announced GPS would be made available to everyone, seatbelts became mandatory and Austrailia II won the Auld mug. We have 2x110Ah domestic batteries and a separate engine battery now.
snooks
Active member
UPDATE
Just to update everyone....
I went for a Beta 30 with a 2.6:1 gearbox and a 3 bladed 15x12 flexofold in the end.
Everything on the engine was in the right place for the boat, the lower revs=quieter running has proved true, we can cruise at about 4.5-5 knots at lovely quiet and effortless 1700 rpm in flat water, about 5.5-6kn at around 2300. 7 knots at 3300 and the cockpit drains are full, 3600 and the back of the cockpit is under water! So I don't think I'll be using 3600 unless I have to
We also re-soundproofed when we had the chance with Noisekiller. The engine itself is much quieter and smoother. My wife and I can now have a conversation when she is sitting below in the saloon, where as before at the bottom of the companionway steps it would be a struggle to hear someone in the cockpit.
What the extra power has given me is the ability to reverse in any direction I want...With the Bukh and a 2 bladed prop I could only reverse to port, as the engine took so long to increase revs the prop walk would send the stern to port long before the boat would start moving astern and the direction could be controlled by the rudder, even then I couldn't reverse down a long marina alley without having the wind dead astern.
So while the Bukh would run continuously at a set speed, in close quarters situations it never had the speed to increase the revs fast and get the prop spinning fast quickly to be able to manoeuvre, start and stop efficiently the way the Beta 30 can.
Was it worth it? Time will tell. It's smoother, quieter, lighter and more powerful. Some of the advantage has come from the propeller for sure, but the engine has done everything I had hoped it would do and more - The "more" being the ability to reverse to starboard in a tight situation, and turn in control without the wind getting hold of me as I wait for the engine revs to increase
Just to update everyone....
I went for a Beta 30 with a 2.6:1 gearbox and a 3 bladed 15x12 flexofold in the end.
Everything on the engine was in the right place for the boat, the lower revs=quieter running has proved true, we can cruise at about 4.5-5 knots at lovely quiet and effortless 1700 rpm in flat water, about 5.5-6kn at around 2300. 7 knots at 3300 and the cockpit drains are full, 3600 and the back of the cockpit is under water! So I don't think I'll be using 3600 unless I have to
We also re-soundproofed when we had the chance with Noisekiller. The engine itself is much quieter and smoother. My wife and I can now have a conversation when she is sitting below in the saloon, where as before at the bottom of the companionway steps it would be a struggle to hear someone in the cockpit.
What the extra power has given me is the ability to reverse in any direction I want...With the Bukh and a 2 bladed prop I could only reverse to port, as the engine took so long to increase revs the prop walk would send the stern to port long before the boat would start moving astern and the direction could be controlled by the rudder, even then I couldn't reverse down a long marina alley without having the wind dead astern.
So while the Bukh would run continuously at a set speed, in close quarters situations it never had the speed to increase the revs fast and get the prop spinning fast quickly to be able to manoeuvre, start and stop efficiently the way the Beta 30 can.
Was it worth it? Time will tell. It's smoother, quieter, lighter and more powerful. Some of the advantage has come from the propeller for sure, but the engine has done everything I had hoped it would do and more - The "more" being the ability to reverse to starboard in a tight situation, and turn in control without the wind getting hold of me as I wait for the engine revs to increase
Conachair
Guest
Thanx for the update, I´m heading beta way as well to replace a bukh 20.
KINGFISHER 8
Well-known member
Just to update everyone....
I went for a Beta 30 with a 2.6:1 gearbox and a 3 bladed 15x12 flexofold in the end.
Everything on the engine was in the right place for the boat, the lower revs=quieter running has proved true, we can cruise at about 4.5-5 knots at lovely quiet and effortless 1700 rpm in flat water, about 5.5-6kn at around 2300. 7 knots at 3300 and the cockpit drains are full, 3600 and the back of the cockpit is under water! So I don't think I'll be using 3600 unless I have to
We also re-soundproofed when we had the chance with Noisekiller. The engine itself is much quieter and smoother. My wife and I can now have a conversation when she is sitting below in the saloon, where as before at the bottom of the companionway steps it would be a struggle to hear someone in the cockpit.
What the extra power has given me is the ability to reverse in any direction I want...With the Bukh and a 2 bladed prop I could only reverse to port, as the engine took so long to increase revs the prop walk would send the stern to port long before the boat would start moving astern and the direction could be controlled by the rudder, even then I couldn't reverse down a long marina alley without having the wind dead astern.
So while the Bukh would run continuously at a set speed, in close quarters situations it never had the speed to increase the revs fast and get the prop spinning fast quickly to be able to manoeuvre, start and stop efficiently the way the Beta 30 can.
Was it worth it? Time will tell. It's smoother, quieter, lighter and more powerful. Some of the advantage has come from the propeller for sure, but the engine has done everything I had hoped it would do and more - The "more" being the ability to reverse to starboard in a tight situation, and turn in control without the wind getting hold of me as I wait for the engine revs to increase
I know it's a rude question but I'm at the contemplation stage with a Bukh 20 to Beta 25/30 change ... have had a Beta 35hp 4 cylinder in a boat I'm just selling which I was very happy with ........... had a £7k quote over a year ago (30hp) for the whole deal (shaft,prop,installation etc) including everything ...... ball park figure now?
snooks
Active member
LIBS prices:
Beta 30 £4640 inc VAT
Beta 25 £4415 inc VAT and 70A
Here's what else cost me money:
1 X Stainless steel high rise exhaust (bespoke)
1 X 25mm Stainless shaft
1 X PSS shaft seal 25mm
1 X 25mm x 1 1/2" Cutlass bearing
1 X Vetus type siphon break airvent V
1 X Vetus type 330 Water strainer 19mm
4m X 19mm Fire retardant waterhose (Vetus)
1m X 50mm Exhaust hose
2.5m X Fuel hose 8mm
1m X Fuel hose 10mm (Pssfeed)
1m X 16mm Heater hose calorifier
1 X Pss tee piece for waterfeed
1.5 X Battery cable and ends 35mm2
1 X 1/2 UNF fuel filter tail
Bolts /steel for engine beds etc
Hose clips: 1 box of 10 25mm – 35mm, 1 box of 10 11mm- 16mm
1 X 50mm end fitting for Vetus LP type box
1 X Flexible Coupling
1 X Flexofold 15x9 3 bladed prop
1 X Prop Protector
1 X DZR Seacock
1 X Bronze skin fitting
1 X Tail piece
Soundproofing
Engine lift out/in
And add labour on top...Still around 7K
You can save money by doing bits yourself....I just got TS Marine to do the bits I wasn't confident about...Physically fitting the engine and shaft and aligning it 2 days from them. engine soundproofing took about a day, but I got someone else to to that, and it took me around 3 "days" working alone (If I didn't have a 3 hour trip to the boat and 2.5 hours back again I could have done it in less time.)
It took 3 hours to disconnect the old engine, a day removing the old soundproofing and cleaning the engine bay, and a day plumbing it all back in and fitting the prop and cutter.
KINGFISHER 8
Well-known member
Thanks very much for that ... extremely useful ... my quote was for having it all done ashore at Universal up the Hamble ... think the lifting in and out was extra to the £7k.
snooks
Active member
TS Marine fitted my engine, can't recommend them enough, really good to deal with...They have their own mobile crane, but I had to pay Deacons to lift the old engine out and the new engine in.
Rafiki
Well-known member
It nmay be a bit late to reply, but my advice would be to go for BUKH 24. It will just slot in perfectly with no chnages to prop, prop shaft, fuel lines, in fact annything at all. In fact you could even keep all your old wiring and just plug that in (but that's probably taking economy too far.
I did this 18 months ago and paid an engineer to do most of the work, the cost of which was more or less the price I received for my second hand engine sold via the Westerly Owners website.
ther apparent price advantage of a Nanni or Beta is quickly eroded by the extra costs of making it fit . They all say that special feet will ensure a new engine fits the existing bearers but is every dimension of the engine the same, I'm sure you need a new prop shaft and new prop in most cases.
In fact the engine I used was a second hand 24 bought from a marine engineers in poole via ebay ( so there was arisk factor involved!).
I did this 18 months ago and paid an engineer to do most of the work, the cost of which was more or less the price I received for my second hand engine sold via the Westerly Owners website.
ther apparent price advantage of a Nanni or Beta is quickly eroded by the extra costs of making it fit . They all say that special feet will ensure a new engine fits the existing bearers but is every dimension of the engine the same, I'm sure you need a new prop shaft and new prop in most cases.
In fact the engine I used was a second hand 24 bought from a marine engineers in poole via ebay ( so there was arisk factor involved!).
snooks
Active member
Are you really sure about that?
New Bukh DV24 £8223 inc VAT
New Beta 30 (LIBS price) £4640 inc VAT
£3500 difference.........For that I could get someone else to fit it, the engine lifts in and out, have a new shaft, cutlass bearing, stern gland, rope cutter (even a fancy one) a new prop (even dropping a grand on a shiny feathering prop) and new soundproofing, all the pipes and still have change for a very nice meal or two afterwards.
With the Bukh I'd still have old soundproofing, stern gear etc, and be carrying 70 odd KG of engine.
I can now turn on a sixpence, motor the bow through the wind, reverse in any direction I want etc etc
Yes you could go for a 2nd hand DV24 engine, but I had a second hand engine in my boat at the start of the process, why would I want another one?
GreekYiannis
New member
Bukh 20 Rev counter
Hi all. I'm a novice at this boating game. But, I've plunged in and bought a Colvic20 motor boat with a Bukh 20 engine in it. I'm down on a tiny Greek island in a boatyard with a generator that's 60+ years old and a tiny hardware shop on the island. But wonder of wonders - we now have internet!
Does anyone know how I can fit a REV Counter to my Bukh20 engine so that I know when I'm at 2,000 revs - which is its peak performance level - i think. Thanks guys. Oh, and one more thing. Is there a Register of Marine Engines anywhere? I'd like to get into as many networks as possible. I need all the help I can get.
Thanks
Probably because it's the easiest option. Out with the old, in with the new.
Hi all. I'm a novice at this boating game. But, I've plunged in and bought a Colvic20 motor boat with a Bukh 20 engine in it. I'm down on a tiny Greek island in a boatyard with a generator that's 60+ years old and a tiny hardware shop on the island. But wonder of wonders - we now have internet!
Does anyone know how I can fit a REV Counter to my Bukh20 engine so that I know when I'm at 2,000 revs - which is its peak performance level - i think. Thanks guys. Oh, and one more thing. Is there a Register of Marine Engines anywhere? I'd like to get into as many networks as possible. I need all the help I can get.
Thanks
charles_reed
Active member
I believe the xGM series are hand-startable, but once they made the small design tweaks to turn them into xGMxx that ability was mostly lost. They still have hand-cranks but, as you say, lack the flywheel mass to make it practical. Nevertheless, every now and then I try to start my 2GM20 by hand, just to see if I can. Haven't succeeded yet
Pete
I did it once - fuelled by panic and desperation. Never again - after that I revised the wiring and put in an extra battery.
It's possible on GM series because they had the decompressors - but not on the YM.
Further to Snooks query, any 3 cylinder vertical engine will be smoother than a vertical twin and diesel engine design having progressed since the Bukh, all engines will, for a similar power output be lighter, quieter and probably smoother.
Rather than change the sterngear, he'd be advised to go for a very low geared gearbox and probably an engine which will produce much more power than the Bukh (modern engines rev about x 2 the Bukh but have a later peak in the torque curve).
charles_reed
Active member
Welcome aboard Yiannis,
The rev counter works off the alternator - go and talk to a good auto-electrician - and all you need is to fit a modern alternator and a counter.
I got a replacement 100 amp alternator in Agrinio for €69 - brand new and in original box, which would have done the job.
Tranona
Well-known member
If you read the whole thread you will see he fitted a Beta 30. New type engines review to 3600 or 3200 (Volvo). Hardly2* Bukh at 3000.
GreekYiannis
New member
Thanks very much Charles. Finding any kind of auto electrician is impossible where I am. Can I ask you - if you know - is it the case that I need an alternator with an output AT LEAST as much as my battery Amp Hours? I have a new 55 AmpH battery and don't want to run it down for want of output from my alternator. Or is it the case that the alternator, however small the output, will just keep charging until the battery is full? I hope that's clear enough and thanki you in advance for any reply. Best, Yiannis.