Kad 300 v D6 in targa 40

The d6 is heavier than the 300 so when at least one builder changed his production caused much heart ache as the boat sat quite a bit lower in the water meaning they had to use up risers in the exhaust which leads back to another thread!
 
My boat runs on D6 350's and DPH's , my previous boat ran on KAD 300's and out drives (can't remember which type). I can tell you that the D6's will cost you a lot more in servicing and parts (as Volvopaul) says. The D6's are smoother and more powerful but having run both I think I prefer the relative simplicity of the KAD 300's. With the D6's I find my self waiting for the next thing to go wrong. However, as someone previously mentioned, you will benefit from buying a D6 T40 when it comes to selling it on.

Quite right terry, I remember servicing the birchwood with the kad 300- and dpg drives, then you switched boats( sorry couldn't resist ) the first bill was a shock to your system, now your used to it! I'd agree the d range just don't seem as reliable and when they go wrong the memory of£££££ just stays in anyone's mind that have experienced both sets of engines and drives. Well worth factoring in if you keep a boat long term .
 
Thanks Paul. Not sure I will get much of a better opinion than yours.

Perhaps a campaign for old fashioned jerk injection pumps is needed in the design offices of VP. Electronics on my engines is limited to a few gauges and the stop solenoid ! The experience of my pals V42 with his D6's would have me playing golf !
 
Please Sir, can I have some more KADs?

D6 Vs KAD300s, the 300 wins hands down.

Parts are simple and available worldwide, also fitting most of the 42/43/44 range too and quite cheap next to D6 stuff.

No DPH to deal with.

Less stupid, stupid, stupid looms, controls and software to deal with. Blinking nightmare!

Get a Pro to do the tappets once every 200hrs, not a biggie.

There are still a few brand new 300s knocking around if you know where to look.

Just my thoughts after about 6 years.
 
Well yes and no, ill give you an example on jtb boat he needed a priming pump for the fuel filter, in the parts list it shows it as a separate unit, but buying it was a different story, it now comes as a whole assembly , housing , filters, switch etc over £400!!! Plain stupid. Also you cannot re line or bore the d6 block, it's a new short engine. Pistons and liners are available non vp for the kad 4 and 6 pot engine made by ks in Germany.

Thread is interesting as a Green engine outsider and presents muddled picture due to smoke screen caused by associated drive issues.

On the basis of engine alone always considered the 3.6 base engine design is real poor, particularly in 4 valve form, and the over complex 'solution looking for a problem' air handling arragement caused mainly by the fact that it is an oversquare motor appears a product of muddled thinking.

60 Series engines are in a totally different class to the above with solid base engine design. However watch out for long term fuel system part support. Bosch are in deep poo made a huge loss last year, series production of conventional in-line fuel pumps has now finished, still short runs being made to support service, however even that ends this year. Production of some P pumps still ongoing in China but having seen inside some quality is dire...Parts listed as no longer available likely to increase.

Once again as outsider surprised that so little positive comment regarding D4/D6, great power delivery, very sociable, no smoke, low noise and on the face of it simple to service. Agree that parent bore with no service oversize is simply nuts however unlike Europe, boaters in U.S. faced with $14,000-$17000 replacement block bill from VP dealers have adopted a typically American can do approach and machine shops are sleeving D4/6 blocks at around $500n a cylinder which so far appears to be robust fix.
 
Thread is interesting as a Green engine outsider and presents muddled picture due to smoke screen caused by associated drive issues.

On the basis of engine alone always considered the 3.6 base engine design is real poor, particularly in 4 valve form, and the over complex 'solution looking for a problem' air handling arragement caused mainly by the fact that it is an oversquare motor appears a product of muddled thinking.

60 Series engines are in a totally different class to the above with solid base engine design. However watch out for long term fuel system part support. Bosch are in deep poo made a huge loss last year, series production of conventional in-line fuel pumps has now finished, still short runs being made to support service, however even that ends this year. Production of some P pumps still ongoing in China but having seen inside some quality is dire...Parts listed as no longer available likely to increase.

Once again as outsider surprised that so little positive comment regarding D4/D6, great power delivery, very sociable, no smoke, low noise and on the face of it simple to service. Agree that parent bore with no service oversize is simply nuts however unlike Europe, boaters in U.S. faced with $14,000-$17000 replacement block bill from VP dealers have adopted a typically American can do approach and machine shops are sleeving D4/6 blocks at around $500n a cylinder which so far appears to be robust fix.

Early d6 motors now getting around to a time of life where rebuild costs are becoming aware, the filters assembly for one is a big eye opener to any boat owner, I've lost count now how many have failed which you only find out when the boats serviced and off you trundle back to the dealer so you can complete the job a real pita!! So I carry one now along with the water sensor switch which seems to shear off when you undo it as the plastic seems to swell up with diesel around it. A rebuild kit for a typical 3.6 motor is around £2500 plus labour, that figure doesn't even buy one fifth of a short motor for a d 6, then you have to build it and fit new injectors, rebuild costs between the old and new are just bonkers in my view. Then we will start with coolers, can't remember last time I had to replace any kad 300 heat exchanger or intercooler, there already corroding on the d range motor in half the time. No doubt someone in the uk will have a rebuild programme that will suit the mid range pocket owners.

Then the is the dph drive issue, steering rams, hoses, trim rams, trim hoses, all lasting a very short space of time, in fact anything that hangs in the water is fading away or not serviceable in half the time the older style dpe parts lasted, I've got customers with ten plus year old dpe drives that are still on original props, hoses, seals etc.
 
Early d6 motors now getting around to a time of life where rebuild costs are becoming aware, the filters assembly for one is a big eye opener to any boat owner, I've lost count now how many have failed which you only find out when the boats serviced and off you trundle back to the dealer so you can complete the job a real pita!! So I carry one now along with the water sensor switch which seems to shear off when you undo it as the plastic seems to swell up with diesel around it. A rebuild kit for a typical 3.6 motor is around £2500 plus labour, that figure doesn't even buy one fifth of a short motor for a d 6, then you have to build it and fit new injectors, rebuild costs between the old and new are just bonkers in my view. Then we will start with coolers, can't remember last time I had to replace any kad 300 heat exchanger or intercooler, there already corroding on the d range motor in half the time. No doubt someone in the uk will have a rebuild programme that will suit the mid range pocket owners.

Then the is the dph drive issue, steering rams, hoses, trim rams, trim hoses, all lasting a very short space of time, in fact anything that hangs in the water is fading away or not serviceable in half the time the older style dpe parts lasted, I've got customers with ten plus year old dpe drives that are still on original props, hoses, seals etc.

Paul, I can see where you are coming from, however once again blurred picture from all this outdrive junk, no wonder boaters in the U.S have little time for the stuff.

KAD 300 lost Volvo huge market share to Yanmar 6LP which is simple as a wheelbarrow, similar displacement and rated speed as well as being lighter, 408 vs 493 kg great performer without air handling complexity.

D4/D6 Should be more durable than 3.6 by a country mile with exception of the chain driven cam drive. Common rail injectors coming down as PLI injectors going up in price, only about £30 per unit price difference.

What I think you are telling me is that newer engines are far less reliable than older designs due to poor quality marine hang on bits.....
 
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Paul, I can see where you are coming from, however once again blurred picture from all this outdrive junk, no wonder boaters in the U.S have little time for the stuff.

KAD 300 lost Volvo huge market share to Yanmar 6LP which is simple as a wheelbarrow, similar displacement and rated speed as well as being ligher, 408 vs 493 kg great performer without air handling complexity.

D4/D6 Should be more durable than 3.6 by a country mile with exception of the chain driven cam drive. Common rail injectors coming down as PLI injectors going up in price, only about £30 per unit price difference.

What I think you are telling me is that newer engines are far less reliable than older designs due to poor quality marine hang on bits.....

Yes I'd put it that way, the exhaust recall is a major issue, some owners are having to fork out here own pocket in fear of the boat sinking with rotten pipes, no insurer would pay out for faulty manufacture , then there is the extra service costs and of course the engine diagnostics and simple calibration that often can only be carried out by a dealer, should your hcu or engine CPU go down its not just a matter of buying a new one its got to be programmed by the vodia through a dealer and that costs money. I'm still a fan of the older simpler motors. Shame the 6 lp was married to the black drive.
 
I think you know what i mean. The KAD300 is a marine engine. D series is probably not bad in equipment that has 10years life time expected. Like our fork lifts at work or construction equipment

LS you are concerned about prices on fuel injectors. On the KAD nobody buy a complete injector. Only nozzle is needed.
A nozzle which is easy to produse any place in the world.

What about the D series incektors? Is the marked large enough to start pirat production? Wil bosch still produse this nozzle in 20years from now? What will the price be. The volume is not that large.

What about the elektronics? Is this easy to replace in 20 years? Are the brains cheaper then?

The main advantage of a marine diesel engine have always been simplicity and reliability.

The company I work fore have prodused CR marine engines last 15years. Still they have to offer PLD systems for marine customers.

Professionals avoid elektronic engines if they can. Even at large numbers of running hours the fuel consumption reduction cant defend repair and offhire cost.
Getting a skilled trouble shooter out in the north sea a stormy day is also a issue.

How this is on a pleasure engine running 200h a year must be clear. You can't buy a filter for the fuel saving. The loss potensial is large if you have to replace elektronics, fuel nozzles or get corrosjon in a cylinder.

Very sociable. Is that what you have to be when you take friends on a 50nm trip and are using 10h back in limp home mode?

Volvo have made some good engines like 40 and 60series. The new D3 D4 and D6 will never enter my boat!
 
I think you know what i mean. The KAD300 is a marine engine. D series is probably not bad in equipment that has 10years life time expected. Like our fork lifts at work or construction equipment

LS you are concerned about prices on fuel injectors. On the KAD nobody buy a complete injector. Only nozzle is needed.
A nozzle which is easy to produse any place in the world.

What about the D series incektors? Is the marked large enough to start pirat production? Wil bosch still produse this nozzle in 20years from now? What will the price be. The volume is not that large.

What about the elektronics? Is this easy to replace in 20 years? Are the brains cheaper then?

The main advantage of a marine diesel engine have always been simplicity and reliability.

The company I work fore have prodused CR marine engines last 15years. Still they have to offer PLD systems for marine customers.

Professionals avoid elektronic engines if they can. Even at large numbers of running hours the fuel consumption reduction cant defend repair and offhire cost.
Getting a skilled trouble shooter out in the north sea a stormy day is also a issue.

How this is on a pleasure engine running 200h a year must be clear. You can't buy a filter for the fuel saving. The loss potensial is large if you have to replace elektronics, fuel nozzles or get corrosjon in a cylinder.

Very sociable. Is that what you have to be when you take friends on a 50nm trip and are using 10h back in limp home mode?

Volvo have made some good engines like 40 and 60series. The new D3 D4 and D6 will never enter my boat!

Gawd I hate getting involved in Green engine stuff!

#1 Gong rate for rebuilt PLI injector with new genuine Bosch tip is circa £70. Rebuilt Bosch common rail injector is £100 to £110 depending on work required.

#2 No shortage of pirate injector tips about, and that is the trouble, some good from Italy, some junk from India, do you know what you are being served up? Big issue is in-line injector pumps. Incident last year, yard numpty graunched down pump element to try and cure minor fuel leak, cam roller went out of line with cam, pump completely trashed. New pumps from Bosch on four month lead time and now £6K plus, ten years ago same pump was in production and £2K on the shelf. Boating season all screwed up, good job it was lousy year.

#3 PLD system in my book is electronic unit injector, unless you are talking about the old Lucas Bryce mechanical unit injector which was sold to Woodward, super gear, that is until they moved production to Germany, causing reliability to go to heck.

#4 Bosch electronic engine control units can suffer early life failure, however they will live to very old age with no degredation.

#5 My only negative comment was my dislike of the Volvo 3.6 block motor particularly when compared with Yanmar 6LP however people seem to like the motor so who am I to say.

#6 D4/D6 are extremely sociable engines, no smoke and quiet, and perform far better than old generation stuff which should score points with boaters and should never see wear out on pleasure applications. Issues as I see them are Volvo Penta arrogance, marine hang on bits from what VP says are ill thought out and poor quality and the fact that Volvo Penta tightly restrict use of electronic tools to their network. Volvo also seem to be poor about policing installations. However Volvo Penta did a great job scooping up most builders and eliminated competition. Spoke with builders in the U.S. which offer Cat and Cummins, they are told by agents in the U.K, needs to have Volvo Penta option or boat will not sell.

Volvo design brief to Deutz guys was to keep the D4/6 block light, and not to have enough meat for service oversize piston, then to drive the camshaft with a chain drive which is boutique engine stuff, therefore D6 will never be able to do the same job in commercial applications as old 60 Series Volvo.

Some people enjoy living with stink pot engines, personally I do not.
 
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Is there an adjustment so the compressors on the kads come in later? So if you are running at slower speeds for a longer period of time the compressors aren't working.
 
Sorry Latestarter, Deutz has absolutely nothing to do with the D4/D6 engine. It is a VP in-house designed engine (albeit with some consultancy assistance from AVL), specifically designed for marine use.
 
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Is there an adjustment so the compressors on the kads come in later? So if you are running at slower speeds for a longer period of time the compressors aren't working.

Clive, I can fit a switch on the dash so it comes in if you want it to, or to simplify it disconnect the pug to the clutch while on the rivers or when you don't want it at all.

You got some idea up your sleeve then??
 
Hi Clive, ha, what a small world, didn't know you knew Paul, he came out on our sea trial last week on the boat I mentioned to you before you went out to the sun, well not that exact boat but another similar and nicer. Hope you got on ok out there,

Andy & Gail
 
Hi Clive, ha, what a small world, didn't know you knew Paul, he came out on our sea trial last week on the boat I mentioned to you before you went out to the sun, well not that exact boat but another similar and nicer. Hope you got on ok out there,

Andy & Gail

Welcome to the forums andy
 
Hi Clive, ha, what a small world, didn't know you knew Paul, he came out on our sea trial last week on the boat I mentioned to you before you went out to the sun, well not that exact boat but another similar and nicer. Hope you got on ok out there,

Andy & Gail

Hi Andy, yes Paul does the servicing etc on my customers boats down here on the south coast. Hope the purchase is going well. Let me know how it goes, cheers Clive
 
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