bukh?Why bukh?

30boat

30boat

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I'm presently helping a friend rebuild her 20 odd years old Bukh.There was water in the sump wich turned the oil into a gooey mess with the consistency of very thick peanut butter.She had the good sense to stop the thing when she detected a change in note so damage shouldn't be very extensive.The point I'm trying to make here is that this engine is unnecessarily complicated and, of course that reflects on the price.There are counterweights everywhere and also an advance and retard injection timing system.Its weight is astronomical no doubt due to all those extra bits that you don't find in more modern and equally (if not more) reliable designs.
That external flywhell is to say the list menacing and the engine is at least twice as big as my 20hp Beta.
People may say that it was designed with marine use in mind and that they last for ever.Aparently they last for 20,25 years with a few rebuilds along the way.Don't get me wrong this is a good engine but a flawed one.The raw (and only) water pump is patently undersized and for this reason these engines are known for steaming a lot at the exhaust and warping their cylinder heads.
I know of a raw water cooled Kubota that's at least as old as this one but a lot more reliable.
And they are not smooth.At least not at idle speeds.They do vibrate like hell at low revs.
Wer're going to fix it ,nothig more serious than a failed Oring we hope.But I wouldn't buy one new specially not based on reliability.I can get much less expensive engines on the market wich have evolved with time something Bukh failed to do.
By the way I had a Bukh in my Fulmar when I first got her but now there is a little sweet and powerfull Beta in its place.Best decision I ever made,although I have to say I miss the hand start facility.
Any comments?
 
There is nothing complicated about the Bukh engine. If you find it complicated them may I suggest you stick to playing with meccano or even lego.
I had a Beta 20hp in my previous boat and it was a pain in the ass - The agricultural noise of it and the vibration were most annoying. I now have a 18year young Bukh that runs sweet as anything - very little vibration and a reassuring sound. The pump is adequate (just) even on full load provided the waterways are reasonably clear. Being raw water cooled it pays to clean out the waterways periodically. The engine anode gets changed twice a year and the oil, oil filter and fuel filters every 100 hours or there abouts. - so what is your friends excuse? - lack of maintenance?

If your friend's engine is vibrating at low revs increase the RPM to 900~1000 and / or change the engine mounts. If the tick over RMP is too low any engine will vibrate.

I would never change the Bukh for a Beta, If I do need to change (in another 15~20years /forums/images/graemlins/wink.gif) it will be for another Bukh.
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"Artificial intelligence is no match for natural stupidity"
 
I have a Bukh DV10 (single cylinder) The engine has been rebuilt once, it is now about 30 years old. 12 years ago my father and I brought my 28' sloop up the channel from Dartmouth to the Medway. There was no wind at all that week and so the motor had to work for 13 hours a day for 5 days and it performed faultlessly. I laid the boat up for major works and after 12 years with but a little re-commissioning work she started up again.
This is an amazingly simple machine that has proved very reliable and I will buy a Bukh when and if I need to replace the engine.
On top of all this the two directors of Bukh Ltd are extremely helpful and very knowledgeable. Every time I have called them with a query they have spent a considerable amount of time with me making sure I was OK with there advice.

John
 
Cliff, What is the best way to clean out waterways.?

Thoruoghly endorse helpfulness of Bukh UK.

My Bukh 20 is abit slow to start sometimes , cant decide wether its compression or fuel run back starts first crank if warm. My engine is coming up for 22 years and runs sweetly.
 
Entirely agree with Cliff. My engine is now 22 years old and despite getting b**gered when a powder extinguisher went off and seized the rings, has performed faultlessly.

Clearly you must have very little knowledge of diesels to make the statement ""The point I'm trying to make here is that this engine is unnecessarily complicated"", as this is one of the easiest engines for the amateur to work on I've ever come across. Provided you have a full workshop manual, there is little you can't do (aside from machining heads and the like) afloat.

For example, I removed mine into the saloon, stripped it down, removed the pistons etc, and re-assembled it, all at anchor in a swell! No doubt you could do that with a Beta, but how do you then start your Beta when the batteries are flat??

The nonsense about warped heads is hardly worth responding to. I have heard of it twice in about 30 years, both on the '10' as it happens. On inspection, one turned out to have received virtually no maintenance, 'because it always started and ran well (!)'. It had never been flushed out in it's life, and had over-heated!

Tell your friend that ANY engine requires proper maintenance, and for raw-water cooled engines (far simpler IMHO - see the current thread above!) this is important!
It may not, of course, have been your friends fault, but do advise her re this factor to prevent the possiblility of future problems.

Just a footnote about vibration. The setting of the tick-over speed is quite important to reduce vibration. The recommended speed is 'between 900-1100' which IMHO is too broad a range. Below 1000 it vibrates like many other diesels, but from that speed upwards, there is little to choose between them. FWIW we set ours at around 1050 revs, which produces a smoother T-O than anything lower - for OUR engine/boat. Vary the T-O when you re-install to find the best for your friend's set-up.

Certainly 30boat, if you (or an engineer) properly carry out the repairs, your friend can be assured of another long period of reliable life from her engine. She just needs ensure that the maintenance is properly carried out - buts that should be the case with ALL engines - shouldn't it?!!
 
Anyone remember Sabb too? Had one of those that was 35 years old and ran like a champ-Built for the Arctic,eg no impeller but diaphragm water pump,genuine,very very simple ,marine 400lb 8horsepower lump.
So impressed was I that I subsequently bought another - a youthful 22years old this time- for another boat, but I will probably never use it.
 
Isn't it amazing how upset, not to mention rude, people can be if someone criticises their favourite engine? I'm an unbiased observer, very satisfied with my Beta and the previous boat's Yanmar (but having good reasons for hating the Volvo that the Yanmar replaced). However, I hope that I'll never respond to (even poorly informed) criticism of my favourite engine as intemperately as if the insult had been to my wife! Calm down, lads!
 
[ QUOTE ]
Cliff, What is the best way to clean out waterways.?

Thoroughly endorse helpfulness of Bukh UK.

My Bukh 20 is a bit slow to start sometimes , cant decide whether its compression or fuel run back starts first crank if warm. My engine is coming up for 22 years and runs sweetly.

[/ QUOTE ]In answer to your first question, I use Fernox™ boiler descaler, recirculating it through the engine. Do a forum search on Fernox and you will find several posts on the subject.

Below is the method I use.

I used Boiler de-scaler (Fernox™) to de-scale my Bukh (DV24) by arranging a bucket in the cockpit with a feed line to the engine raw water pump and a second bucket under the exhaust through hull fitting to collect the waste coolant and a 12v in-line pump in the second bucket to recirculate the water back to the bucket in the cockpit. Flushed the engine with fresh water (ran the engine under load against the pontoon until temp was up) while allowing the exhaust to discharge to the marina then putting the second bucket below the exhaust and recirculating the discharged coolant. and adding the Fernox™ to the cockpit bucket - took about an hour and a half to do the job and there was a lot of crud discharged. Shut the engine down and allow to sit for ½ to 1 hour then flush with fresh, clean water. After flushing finally with fresh water I removed the anode and had a look inside the block and was impressed at how clean the inside of the block was, at least the area I could see. Same with the thermostat and stat housing. Worked for me (and others) and saved stripping the engine. Usual caveats apply - just because it works for me (and others) does not mean it will work for you although for a testimonial see this thread

As for your poor starting, Try increasing the tick over speed to 900~1000RPM. (adjuster is on the throttle quadrant (where the teleflex cable attach's to the engine). The tick over on mine was too low and following the advise of Bukh UK I increased the tick over speed to 1000rpm - sluggish starting cured. I can balance my beer can on the rocker cover now even with the engine ticking over. /forums/images/graemlins/grin.gif

Seems the fuel pumps on these engines go to "full throttle" when the engine is stopped. As the engine is cranked over the pump initially gives a full dose of fuel and then returns to closed throttle (tick over) position. If this setting (tick over) is too low the engine is liable to stall when cold. Another thing to check is the return spring located below the pump. It can be accessed/seem by removing the plate carrying the stop solenoid. If the spring is not in position, this also can give poor starting. Remember the Bukh do run a little lumpy when first started - for a few seconds until the auto timing kicks in. The engine should run smoothly after 10 secs or so.
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"Artificial intelligence is no match for natural stupidity"
 
\'cos it\'s not the first time....

If you do a search on 'bukh', you'll find this is not the first time 30boat has banged on about these engines; it just gets a bit boring & irritates their many fans - of which I'm one.
 
Hi Nuno, bet you wish you had kept your head below the parapets! As an avid supporter of the Beta I understand where you are coming from. The Vegas also had brick built outhouse type engines as standard (Volvo MD6A) that have lasted 25 - 30 years but there is no way I would even contemplate fixing one of anything major. There have been many advances and just because it works doesnt mean there isnt something better. I find the Beta reliable, economical and quiet. After Sales service is legendary. One VEga owner sailed to Marstarnd last year and coming back there was no wind whatsoever so he engined for near enough 7 days solid (740 miles). Never a falter from the Beta and used less than a litre an hour. Spares are available and at a decent price. I dont say to change for changes sake but if anything major happens then work out the pros and cons. We are all scared of change but dont get eft behind with the luddites.... All in my very humble opinion.
 
Who are you calling Luddites? If the other engine manufacturers ever advance enough to catch up on the Bukh design, simplicity and general suitability for purpose I might entertain one but so far they are all somewhat lacking in various aspects.

Another beauty of the Bukhs is they don't, as a rule, have anything major go wrong with them, (regular maintenance assumed). Longest nonstop run on mine was around 220 hours only stopping once for about 15 mins for an oil and filter change - never missed a beat.

IMHO, anyone who knocks Bukh marine engines is little more then a philistine.
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hammer.thumb.gif
"Artificial intelligence is no match for natural stupidity"
 
Hi dulcibella,

You are quite right about people's bad reaction to criticism and we must all surely feel this from time to time. What makes me and others annoyed, is when that criticism is clearly based on hearsay and innuendo, and not facts.

By all means have a go at Bukh (or any other engine) but for heavens sake let's try and be constructive about it, not condemn things out of hand because we have a severe lack of knowledge and understanding of diesels.

Several of my friends have Betas and are totally delighted with them. They have been reliable and cheap to run, but then my friends aren't long term (and I mean years, not months away) cruising!!! The extinguisher incident for example, happened at anchor in the Cape Verdes, where I'm afraid, Beta's (and Bukh's) no doubt excellent service, ain't a lot of help!!

The reason I chose to stick with Bukh was, as I outlined in my earlier post, that the design allows me to do virtually any repair myself, even in difficult conditions. And bear in mind much of our sailing is done where there isn't an engineer/parts supplier round the corner, so reliablility is paramount.

Whilst I'm sure similarly capable owners could also happily manage major repairs with their Betas, we particularly want the ability to hand start the motor. When, and if, Beta provide this facility, I would readily place them on my 'think about these' list when re-engining.

Frankly, it would be better to seek advice with a 'nicer' approach than our friend 30boat did if he wants help on behalf of his friend. If the idea was just to indiscriminately 'blast' Bukh, well, he must expect a few 'firm' ripostes' mustn't he!!!
 
Re: the water in the sump. It`s worth checking the water pump shaft seals, When these fail water finds it`s way into the engine along the shaft and through the chaincase. Warning signs are water coming out of the tell-tale holes in the pump body. The seals are cheap and easy to replace. There should also be an O-ring between the seals, acting as a thrower. Make sure the tell-tale holes are not obstructed by paint and crud, or by the clamping piece that holds the pump in place.
 
[ QUOTE ]
If the idea was just to indiscriminately 'blast' Bukh, well, he must expect a few 'firm' ripostes' mustn't he!!!

[/ QUOTE ]"Firm" - I like it - always the diplomat! /forums/images/graemlins/smirk.gif......../forums/images/graemlins/grin.gif
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hammer.thumb.gif
"Artificial intelligence is no match for natural stupidity"
 
Geting back to the initial problem,
I had water get into my Bukh 20, it was caused a few years ago when I went up the river to Totnes and the fresh water in the raw water cooling partially froze and pushed out one of the core plugs in the cylinder head (under the rocker cover). This is a pretty easy fix the new plugs are slightly domed and you clean up the head where the old plug was add a smear of sealer and insert the new plug and tap it in with a drift (1/2" drive extension bar) as the plug flattens out it gets bigger and is a tight fit.
I stripped off the head and sump and cleaned out all the gunk I could and then flushed with fresh oil (head still off) with the starter till fresh clean oil came through the oilway, then again with the head on but with the rocker off till clean oil came through the oil supply to the rocker, I then reassembled and changed the oil and started and ran the engine for about twenty minuites, I changed the oil again ran for another twenty minutes three times in total, refitted the engine in the boat, that was three and a half years ago. PS my engine doesent vibrate.
Also I need a new starting handle anyone know of one for sale?
 
30boat said:
I'm presently helping a friend rebuild her 20 odd years old Bukh.There was water in the sump wich turned the oil into a gooey mess with the consistency of very thick peanut butter.She had the good sense to stop the thing when she detected a change in note so damage shouldn't be very extensive.The point I'm trying to make here is that this engine is unnecessarily complicated and, of course that reflects on the price.There are counterweights everywhere and also an advance and retard injection timing system.Its weight is astronomical no doubt due to all those extra bits that you don't find in more modern and equally (if not more) reliable designs.
That external flywhell is to say the list menacing and the engine is at least twice as big as my 20hp Beta.
People may say that it was designed with marine use in mind and that they last for ever.Aparently they last for 20,25 years with a few rebuilds along the way.Don't get me wrong this is a good engine but a flawed one.The raw (and only) water pump is patently undersized and for this reason these engines are known for steaming a lot at the exhaust and warping their cylinder heads.
I know of a raw water cooled Kubota that's at least as old as this one but a lot more reliable.
And they are not smooth.At least not at idle speeds.They do vibrate like hell at low revs.
Wer're going to fix it ,nothig more serious than a failed Oring we hope.But I wouldn't buy one new specially not based on reliability.I can get much less expensive engines on the market wich have evolved with time something Bukh failed to do.
By the way I had a Bukh in my Fulmar when I first got her but now there is a little sweet and powerfull Beta in its place.Best decision I ever made,although I have to say I miss the hand start facility.
Any comments?
Click to expand...

Which model of Bukh are you posting about ??

The 24 and 36hp, (Bukh figures are continous SHP), keel cooled lifeboat engines are not complicated, BUT they are heavy and rather bulky in comparison with a modern but far weaker Yanmar. They should be fitted with flexible mounts and far more reliable keel cooling. (standard fit for a lifeboat), will need a silencer to be as quiet as an equivalent Yanmar.
The 24 and 36hp models are regarded by most dieael engine experts as a classic case of you get what you pay for, and they are the most expensive diesels around if you buy a new one. The 36 is around 10,000 gbp and that's without any extras!

PS: I would steer well clear of a direct or salt heat exachanger cooled version, as they were designed for keel closed loop or tank cooling. Not daft suck and spit systems!
 
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