hi everyone. first post
I bought first yacht last week.. was neglected 4 years!!! mangrove jack at that.
engine ran fine at first.. then burst hose above waterlock which slightly melted!!
its blowing visible light blue smoke same idle or under way.
yesterday it started one cylinder, 2nd kicked in moments later. today its 1 cylinder only..
I'm flying to get my tools. be back Tuesday but I'm still overwhelmes re diesels and finding bukh specificstep by step trouble shoot and actual workshop manual.
it looks like dv20 or 24? supposedly 30 hp..
insights and questions much appreciated ..

Gidday des here from Valkyrie, I sold you that anchor winch last week. Sorry but your name has slipped my mind, sorry to here you are having engine troubles. Your not alone I'm stuck in a camp area waiting to get my car fixed next week 'clutch'. I was very lucky for my bonnet was only up 5mins and an NRMA came by and towed me to a camp site and workshop for $50.
As for your motor I recommend starting at the fuel tank and clean/ inspect every bit. Have your injectors cleaned too and I did't think there was much smoke when we went for a sailing lesson.
Hope you don't have to strip it down, oh and clean all your cooling system eg. Heat exchanger, and check your pumps too. As the engine has been sitting it may be clogged up in the cooling parts.

First thing to check is the condition of the oil for water contamination due to a blown head gasket. When it's running the simplest check for overheating is to put your hand under the the exhaust outlet and if the waters just warm that's O.K. If it's obviously too hot to leave your hand under then it's running too hot and you need to work your way through the cooling system starting from the seacock through to the raw water pump and right through to the exhaust elbow making sure the impeller is OK and there are no blockages in the lines. I once owned a Bukh 20 that over heated with steam coming out the exhaust and the problem turned out to be a small piece of scale that had come loose and was blown clear from the water blasting during a slipping and lodged up the line allmost completely blocking the passage of water to the pump. Also exhaust elbows when combined with salt water, carbon and heat will build up a residue that will eventually bring about an allmost complete blockage.
First things first. Whatever else is causing it to run on one cylinder you have a heating problem and you will have to rectify that anyway before you solve whatever other problems are or might be related to your missing cylinder and blue smoke issues.

If he put a new impeller in recently you need to ask him what happened to the old one......if it failed its possible the blades are stuck in a elbow or water jacket which will restrict the water cooling the engine , if you have melting water jacket it's very evident your not pumping water. My mate (master5) med 2 run my little 1 cylinder without checking the sea cock was on....melted the water jacket and was lucky not to damage the engine.

You should have water squirting from your exhaust like a bit of hose pressure not a little dribble.

You don't need to muck around with the fuel tank to much just crack a hose and fill a glass with fuel and check it looks like diesel......if there is water the fuel will float to the top of the glass. I really doubt it is the fuel tank as one piston is firing .....

Anyway have fun and good luck.

marine guys just wants me to book in for few hours compression test. and overnight fuel injector...
I've read somewhere somehow filling cylinders with oil and see if can crank :/
see I called these brokers at marks point to see a yacht, sure c'mon up!!! I flew up, lo and behold the boat already sold long ago!!! I spent months preparation.. anyway as I was going to go back to melbourne these bassards called me up and pushed me to spend all my money on a acht I wasn't prepared for.. so all I have is maybe if this bukh be too much a problem then id have to plant my petrol ute engine in it!!! meanwhile I need to put put around

I have uploaded the dv20 workshop manual here. hope it helps

drive.google.com/file/d/0ByPudmUjZep-b2NxUGFmZG9VNEk/edit?usp=sharing

On my early volvo penta there is a 3 position lever. Usually it is tucked in and not noticed. raised into the middle position the engine compression is reduced. In the fully extended position only one cylinder works. It's purpose was to allow starting the engine by hand cranking easier (in flat battery situation). Once started the lever was folded back in and the second cylinder started up. I think this lever has been deleted from later versions as I doubt anyone starts these things by hand anyway.

yeah, wow.. been getting numbers to call then waited weeks for this guy only to find oit I need insurance to berth at nearby marina and all workberths are booked put for months.. finally got a number for mobile but he says it be a stuck valve and insists on reconditioning the whole head!!! so I take rocker cover off to see everything looking good. seems by hand cranking both cylinders have compression that wait a moment for hissing to stop to keep cranking. all valves and rods looking good.. so I will see what he says tomorrow when he comes for preliminary look at motor. its prolly water system clogged and possibly also fuel injector. the hell its so impossible to find a simple backyard diesel tinkerer to solve simple things that's costing me all the world to completely over recondition.. this just a solid 30 yr old motor done 4000 hours >.>

If the guy is good ie won't try to rip you off, he should first determine whether or not the valves are sticky in the guides and whether they are sealing on compression stroke.

If they are good he should then recommend at the very least that both injectors are removed and pressure and spray pattern tested and while that is being done it would be a good idea to remove the injector pump and bench test and calibrate it at the same time.

If the valves are not good, the cylinder head needs to be removed and it and the valves need to be reconditioned in the workshop AND the injectors and injector pump still need to be done as well.

However if the cylinder head is removed, before anything else is done the cylinder bores should be inspected and measured to determine if the engine needs new sleeves, pistons and rings and if it does you might as well pull the engine out for a full recondition.

If that is the case you should consider a new engine and not a Bukh. The only new engines Bukh are producing are the 24 hp model specifically designed for life boats.

A reconditioned DV 20 Bukh is going to cost you $8,000 plus fitting.

www.bukhdiesel.com.au/recons.htm

The same people also sell Beta Marine diesels.

www.betadiesel.com.au/#

If you do need to get another engine, I would go with the 20 hp 3 cyl Beta (incl gearbox) for just under $9,000 plus fitting rather than a recon Bukh. They are Kubota based and very well marinised in the UK. Whatever you do do not get a Nanni marinised Kubota. I had one and their marinising is crap.

So, best case scenario, you get your injectors and injector pump serviced/repaired. Second best scenario, you do that and have the head done up.

Worst case scenario, engine replacement. A 3 cyl Yanmar 3GM 30 would be a good option too but the heat exchanger model. Shop around. Stay away from the "Green Death" Volvos.

I really hope its simple.. I can almost think I could manage this. one can always kick himself in my predicament but sometimes its easier to go with the flow as there is a nutter with a god complex already influencing so we're just waiting for the threat to pass and police to clean up the mess. else more peeps would be appropriated in thar orchestration... I will be delighted say if I find an abandoned yacht out at sea then swap myself around..
now the problem with film of oil in the bilge.. coming from sump gasket. one fella told me to use a biodegradable degreaser and flush the mess out thru pump!! I already filled a jar with some crude but was all I could do to wrap it in plastic and hoped it didn't self combusted in the council.. if I had to do an oil change I suppose I drop used off at service stations..

mate, I'm gunna get kicked here..
turns out, in one of the aft cabins is an emergency fuel cut off cable that I must have kicked in my sleep
but waterworks is restricted and running hot so organised an acid treatment and new hoses.. good thing I get to know my way around the bukh as bruce went over it.
and maybe after 50 hours or 6 months it will need service and new fuel lines.
this forum and all the posts have been great and made me more aware of stuff around my floating motel room...

Cisco, interested in your comments on the Nanni. Boat I've had for a couple of yrs came with a newish 3 cyl 21HP Nanni with only about 50 hours on the clock. What were your observations on shortcomings in the ''marinising'' and is there anything you suggest one should keep an eye on?

my water lock smoked up!!
I replaced an old hose that gone hard in case it gotten airleaks, tried to take off that 3-way pipe on the block, then screwed back on as id a had to remove the flywheel to pull it out...
sooo... I just sprayed wd-40 in both ends until dribbling back out.. cured the blockage .. saving me $900 quote to descale. lucky I kept the old waterlock that had partially melted but still had enough to bolt back on.
I noticed inside my air filter/strainer and in manifold has sooty black gritty gunk layered inside.. is that a problem?

Hi Mangrovefrog
What part of Port Philip Bay are you moored in? if you need a hand some time give me a yell