Antares 10.80 Repower D3 220’s

Your engine (and mine) also don’t have liners and some regard as disposable
It is not the lack of liners that is an issue, but the problems of marinising a high revving lightweight engine with lots of aluminium parts, belt driven cams and ancillaries with electronic controls and common rail fuelling, when these things were in their infancy. (see photo in post#13) If you read the numerous stories on the net and talk to Volvo dealers you will find what the real problems were. The type of duty they were aimed at would not test long term mechanical wear, but all the usual problems of short bursts of use followed by long periods doing nothing but being full of corrosive seawater then further short bursts of running either at low speeds or near flat out. Very different from being used in Volvo taxis in Sweden where 200k kilometers is normal life.
 
I just would really like to know is there would be a power difference in speed, economy with repowering from kad300s to d3220s in a Antares 10.80

Not sure if the weight difference will affect the boats trim and stability on plane up to a bow heavy condition . The weight difference is significant so i would consider this
 
Your engine (and mine) also don’t have liners and some regard as disposable
Yes, you are right, qsb 5.9 can drill/hon cylinders in a block, but if you maintain it well and are lucky, you can find a charter boat with twin engines that has logged over 25,000 hours without any major repairs, and everything is fine. (Seaboard Marine Forum) I only have about 3500 hours of light use, so I'm not worried.
 
With the research I have had thanks to ‘Little Ricky’ is that many boats such as the Jeanneau NC 37 were fitted with these engines which is by comparison is the same hull length 9.9m, larger beam of 3.59m to Antares 3.44 and heavier displacement of 6832kg to Antares 5900kg. The Jeanneau NC 37 with these engines is hitting top speed of 28knts and cruising at 21knts, remembering the boat is heavier. The kad300 engines I have is going to cost me around 20.000€ + (removing and replacing parts) and that still does not give me piece of mind that something didn’t get overlooked, also they are 20 year old engines which will never match the knts that and fuel economy that D3’s will give and only 5 years old. The biggest flaw to the kad300’s are the compressors, they are only there to spool up the turbos, they are not designed to be driven for long periods of time with them engaged, that means from 1500rpm to 2800rpm is were you should not be for long periods of time ( drive 8knts or 17knts but not in between ) the compressors wear out very fast ‘if’ the sensors switch them off and a replacement is 5000€ per compressor.
I don’t understand the hate to the d3 engines as all engines have to be looked after and serviced regularly, the turbos on the kad300 is something I replaced recently and such all turbos should be replaced or refreshed with stainless parts every 3-4 years, it’s cheaper then replacing compressors.
Most of this is nonsense ( I ve run Kads for 30 years) but you have decided you dont want to repair the Kads and you want to put in some lightly engineered D3, despite the wealth of information offered.
As you say, you came on hear to ask if anyone has retro fitted D3s, and you did not come on hear to listen to objective comments about those engines.
Go ahead.
It doesn't seem anyone thought it a good idea to retro fit them on your size of boat. You must SURELY know the reason that builders offer some undersized engines is that it brings the price down massively. Does it make for a lousy boat? Often.
Anyway, hope it all goes well for you and you get to enjoy your boating.
 
Yes, you are right, qsb 5.9 can drill/hon cylinders in a block, but if you maintain it well and are lucky, you can find a charter boat with twin engines that has logged over 25,000 hours without any major repairs, and everything is fine. (Seaboard Marine Forum) I only have about 3500 hours of light use, so I'm not worried.
Yes, they are in reality commercial engines able to go forever rather than recreational
 
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Most of this is nonsense ( I ve run Kads for 30 years) but you have decided you dont want to repair the Kads and you want to put in some lightly engineered D3, despite the wealth of information offered.
As you say, you came on hear to ask if anyone has retro fitted D3s, and you did not come on hear to listen to objective comments about those engines.
Go ahead.

Of course no sane boater throws away a rebuildable kad300 to repower with a d3 but the OP made a decision so i try to stay on the subject . It sounds for me like bad mechanics not understanding the kad engine .

Like said not sure how the weight difference of the new engines would affect handling of the boat .

most probably its also opening a can of worms since the engine mounts will not fit , the entire engine wiring and controls must come new , engine instruments and much more also , to only find out a d3 is way inferior to a kad300 especially in torque so the gearing is wrong , the prop selection also.

That are all things the OP should consider imho .
 
Most of this is nonsense ( I ve run Kads for 30 years) but you have decided you dont want to repair the Kads and you want to put in some lightly engineered D3, despite the wealth of information offered.
As you say, you came on hear to ask if anyone has retro fitted D3s, and you did not come on hear to listen to objective comments about those engines.
Go ahead.
It doesn't seem anyone thought it a good idea to retro fit them on your size of boat. You must SURELY know the reason that builders offer some undersized engines is that it brings the price down massively. Does it make for a lousy boat? Often.
Anyway, hope it all goes well for you and you get to enjoy your boating.
Not sure that your aggressive tone is warranted here. People give their opinion and based on the D3's massive use within the industry, to dismiss or ridicule those comments based on boat owners own experience is not sensible.
 
The OP came to the forum with a question regards the suitability of a specific power unit to replace a pair of previously problematic ? KAD 300 engines in a particular boat.
The overwhelming replies to the question on this forum from folks with actual real world experience amounting to many years of boating and in one case proffessional experience, is that a pair of properly repaired and refurbished KADS are more likely to provide a reliable long term way of powering this craft than the proposed replacements.
Am going to assume that one or all previous owners have not serviced those KADS properly leading to delayed maintainace coming back to bite the present owner in spades , this skipper just wants to see the back of his existing engines and how could things possibly get any worse, its surely just a simple swap and off into the sunset.
Very much doubt the quantity or quality of advice given on here could be found anywhere else. ?
Would take a pair of lazy large capacity 6 cylinder lumps over a stressed to the limit 4 pot screamer any day of the week. (y)
 
If the original engines are beyond economical repair…and a like for like replacement is more than the boat is worth…then smaller replacements with a good provenance is fine (assuming they fit)…so what if the boat can’t go as fast or even get on plane. Some use out of the boat is better than no use…lots of boats on rivers are way underpowered straight from the manufacturer
 
If the original engines are beyond economical repair…and a like for like replacement is more than the boat is worth…then smaller replacements with a good provenance is fine (assuming they fit)…so what if the boat can’t go as fast or even get on plane. Some use out of the boat is better than no use…lots of boats on rivers are way underpowered straight from the manufacturer
To everyone who has given me advice till now I thank you but I think everything has gone a bit overboard with the comments coming in.
There are a lot of people stating I am crazy to replace the kad300’s I have but not understanding how much time and money I have already invested into trying to save these engines. I had originally purchaced the vessel in France and drove 13 days back to were I live in Croatia. The oil and filters in the engines (as to my request) was changed before embarking on a trip like this. I took me 13 days because one compressor then the other ceased during our trip and drove 8knts across the Adriatic from Italy to Croatia. When we went to service and repair the engines I saw that the 20 year old engines had never been serviced and was the first to replace the belts. So you can understand the state of the engines. Till date I have invested around 25.000€ into the engines and to completely repair them I will need to remove the engines and invest another 20-35.000€ into the engines to see if engines from 20 years ago are still working, parts for kad300’s aren’t cheap.
When do I cut my loses, maybe try to recoup some of which I have lost and rather invest into something more modern and maybe more reliable. I was told will have to change controls, gauges and wiring….i am aware of this and is not a problem due to me completely remodeling the boat. Maybe I would like to know how much I am burning when I go on long trips.
I have been told numerous times that the ‘whole’ community has told me that I am wrong, there has been 4-5 people who have commented but I would honestly, with out any ill will, like to know who has real world experience with the D3 220 engines, where I live here in Croatia, boating is a very big part of our lives as a lot of us come from the islands and are also very knowledgeable when it comes to do about engines, looking after and serving is something we don’t take lightly, there are still a lot of one cylinder 60 year old engines still in service. All advice here is that the D3 220 are reliable but what like every engine needs to looked after. They are engine blocks from cars but are not repurposed after being used in a car. They are marine engines designed for marine use.
I have come to this platform for more insight, as I think the more knowledge the better, and I thank you all but what would you do in my position; A. Try save the beloved kad engines spending another real world 35.000€ or B. Walk away from the kad’s.
Thank you.
 
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Not sure if the weight difference will affect the boats trim and stability on plane up to a bow heavy condition . The weight difference is significant so i would consider this
Thank you for the advice, something really to consider, still also have to take in is that it is still a close to 6 ton vessel with trim tabs
 
Be interesting to know if the existing reverse gearboxes will bolt directly onto the D3 engine block or will require some sort of custom mad adaptor plate. ?
Apparently No is the answer, will need a couple of adaptor plates made, there are a couple of places in UK who fabricate for other engine/gearbox combinations.
Price Book - Page 47
Will the prop shafts need to be shortened or require new longer shafts and what about prop pitch ?
 
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Maybe I would like to know how much I am burning when I go on long trips.

About the same , give or take .

The kad300 is a direct injected engine known for its good specific fuel consumption . The common rail d3 will be no worse but also do not expect it to be significantly better . With comparable specific fuel consumption ( g/kwh) it boils down that your boat for a given cruise speeds needs the same power input on the props whatever engine does the job .

On the take side you will carry less weight with the d3 , on the give side you will run higher rpms for the same speed since you will need lower gearing / props to not lug the new d3 .

Do really not expect any significant fuel savings in comparision to a kad300 .
 
I'm spectacularly no expert, but I have been around boats since I was old enough to wrestle a tiller on an outboard.
There's lot's of good advice on this here already. Anyhoo, my 2-pence worth.....
If re-engining a boat with much more power, there's a surplus of power to create a margin around the lack of serious calculations for gearboxes, prop sizes and pitch, plus centre of gravity for the hull, among loads of other stuff that won't be trivial. If the boat runs bow heavy, you may need ballast at the stern, so you'll have a heavier boat on less power.
If doing this yourself, you may loose the season completing the work and ironing out the bugs.
Boat makers don't do engine installations by chance, good ones work out all those details to match that stuff perfectly. Well, they do until it affects the bottom line, then they adjust a bit in their favour and lie a bit on the performance figures, but you get my point.
If I was to re-engine, it would either involve a suitably qualified marine engineer to do all the calculations and establish as near as possible all the outcomes (plus budget for tweeks), or I would be using pre-refurbished engines of exactly the same type.
Hope it works out for you whatever you choose to do.
 
If these adaptor plates are ones that have been fabricated before ( which is doubtful) around £700 per plate, one off custom .....lots more ?
How about matching number of shaft splines and pressure plates ?
 
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