280DA how to set the best throttle,drive trim and trim tab

[melida]

Hi guy's

Have just bought (in june) a 275 Sundancer with a KAD300 diesel engine and DP-G drive.
I have experienced some of the same problems as Melida, regarding very slow acceleration.
The boat weight app. 3.000 kg + fuel, water equiment etc, in total app. 4.100 kg.
Topspeed is 34 knots at 3.600-3.700 rpm (as I remember). Max. rev. are 3.800 rpm for this engine, mentioned in Volvo's manual.
I can get the boat planing by bringing the trimtabs full down and the drive to -5 (which is the lower limit for my engine at the time).
I don't know the propeller size yet, as I haven't been down under yet


I found a thread on this site, where a norwegian guy and his Sundancer 280 experienced some of the same problems, but he solved his problem by changing props to a lower number. Only loss was -2 knots in topspeed.
Melida: Can you tell me, how many seconds it takes for you to reach 20 knots, and topspeed?
And was there a big difference in acceleration, when you used the other set of propellers?

ClasG,

First of all congrats of your new to you boat.

Your 260 has the similar cockpit layout with my 280 and with KAD300 it is a perfect choice.

I’m assuming you did hull and engine survey before buying and everything went ok.

KAD 300 is rated 285hp at 3900rpm wot, 570Nm torque 3600cc volume, inline 6 cylinder, 24 valve (4 per cyl), compressor (supercharger), turbocharger, aftercooler, mechanical injection pump governed by an electronic engine system, no throttle cable plug and play electronic harnesses.

When I bought my boat in feb 2009 it had ¾ tank diesel and had no acceleration problem until refueling. After refueling only me onboard boat did well, but me and my wife it couldn’t plane and stayed at 2700-2800 rpm where I needed to achieve 3000rpm to lower the bow while trim tabs fully deployed and drive fully trimmed in -5 degree.

Long story short I extended (after buying C3 prop set and didn't satisfied me) the standard 35cmx35cm trim tabs to 40cmx50cm and now I’m happy with it. BUT I must keep the props, leg, trim tabs and water lines(side and transom) extremely clean.

I was onboard last weekend with 6 people (3 heavy man and 3 women) and my 18kg daughter, lets assume 550-600kg, full fuel, full water and ¼ holding tank, my personal/boat stuff app. 50kg and provisions for 6 people. Weather was 35C hot but wind was blowing 4-6 Beaufort and boat did perfect. Men sat at port lounger and I was at the helm women at aft boat planned at 3100 and I cruised at 3200 rpm (21knots) drive trim at 0 and trim tabs fully retracted for not fell-off plane while hitting a big wave.

But we took one more women (70kg) and headed to a head see engine couldn’t pass 2750-2800 rpm then 2 men went to cabin and sat on vberth rpm increased and at 3250 we were fine.

I’ve never calculated the planning seconds BECAUSE I’ve never and you musn’t kick down the throttle in diesel engine and especially if it has both kompressor and turbo. KAD300 has a bypass system when you do kick down and it bypasses the compressor which engages at 1500rpm and gives hand to turbo at 2500rpm. If you hammer down you can’t benefit the boost of compressor and engine starts to create lower boost at 2500rpm for turbo instead of high boost prepared by compressor. So you can't plane faster than doing steady throtle opening, also takes more time.

For planning I always wait my engine warms up to 70C (85C on plane) then gradually do a steady throttle opening while trim tabs fully down and drive trim at -8. After reaching 3000 rpm which is my sweet spot I raise the drive to 0 and fully retract the trim tabs. Also raise the drive to +1 +2 if it won’t decrease speed according to load and sea conditions. My speed is 18,5-20,5 knots at 3000rpm and my fast cruise it at 3500rpm 25-27 knots while drive trim is +5. Wot at 3900 (also does 4000) 32+ knots.

Before enlarging the trim tabs I bought C3 prop set. It helped to plane very faster than C4 set (I currently have them) but boat planes at 3500rpm which is the max permitted extended cruising rpm 10% less than wot. And also my speed is same with c3 prop set at 3500rpm like C4 set at 3000rpm 18,5-20,5knots. So I can’t benefit the extra power/speed of engine. Therefore replaced the props to C4 and enlarged the trim tabs.

If you are thinking to enlarge your trim tabs please read the thread of ”dpmulvey” who helped me before and after of my trim tabs project. Once again thank to him.

 

[Clasg]

Hi Melida.

Thanks for the quick og well described answer.
Sorry I didn't mention, that I was educated as a marine engineer (for +25 years ago) and after examn worked with diesel engines (incl. 65.000 HP main engines) for 6 years , so I did know all the good things you mentioned

I am convinced, that our boats and engines are well-proved and tested as "a perfect match".
Never the less it is my experience, that similar boats can behave different due to the many factors around the boats. Such a little thing as bottompaint (hardracing or self-polishing) can do a great difference.
So "what works for me, maybe won't work for you", if you know what I mean

I was curious about acceleration, as this can be an indication, if the propellers size are correct.

On the other hand, I am totally blank about how Volvo Penta's ECD can control the engine.
Shoulden't ECD prevent overrevolutions of the engine?

I have found this test on the internet, where 5 boats with different engines are tested.
The boat with KAD300 has C3 propellers.
Its in danish, but there are some good figures and general linformation
Hope You can use it as a supplement.
http://www.htbsunds.dk/anmeldelse_filer/136/BM-04.08-SR275.pdf

Before I bought the boat, is was inspected and tested throughout by a suveyor on land.
I did the test drive myself, and at this time, it was in the water and approved by the surveyor.
Therefore I don't have the actual propeller size before next weekend, where I will dive down and read it

I will post it here, when I have experienced a little more

 

[melida]

Hi Melida.

Thanks for the quick og well described answer.
Sorry I didn't mention, that I was educated as a marine engineer (for +25 years ago) and after examn worked with diesel engines (incl. 65.000 HP main engines) for 6 years , so I did know all the good things you mentioned

I am convinced, that our boats and engines are well-proved and tested as "a perfect match".
Never the less it is my experience, that similar boats can behave different due to the many factors around the boats. Such a little thing as bottompaint (hardracing or self-polishing) can do a great difference.
So "what works for me, maybe won't work for you", if you know what I mean

I was curious about acceleration, as this can be an indication, if the propellers size are correct.

On the other hand, I am totally blank about how Volvo Penta's ECD can control the engine.
Shoulden't ECD prevent overrevolutions of the engine?

I have found this test on the internet, where 5 boats with different engines are tested.
The boat with KAD300 has C3 propellers.
Its in danish, but there are some good figures and general linformation
Hope You can use it as a supplement.
http://www.htbsunds.dk/anmeldelse_filer/136/BM-04.08-SR275.pdf

Before I bought the boat, is was inspected and tested throughout by a suveyor on land.
I did the test drive myself, and at this time, it was in the water and approved by the surveyor.
Therefore I don't have the actual propeller size before next weekend, where I will dive down and read it

I will post it here, when I have experienced a little more

Clasg,
Hi again.
I hope I didn’t act as a priggish because you didn’t mentioned as you are a marine engineer.
It’s good to know there is two (the other is Bill/Oldskool) volvo penta/diesel experts in this board.

Searay is the topseller brand in its class in USA and also it’s the most imported brand in my country. In my summer marina the total berth capacity is app 100 boats including 4-5m wooden boats through 20m yachts. There are 11 Searay including mine. My winter marina has a capacity of 1100 boats and there are more than 100 Searays.

There is no need to tell complements to Volvo Penta, it is called “the engine which seas afraid from”. So Searay and Volvo Penta is a perfect match.

As you said even the same hull and same engine can act different in two boats. Different driving style, extra load of people, standard accesorios, dinghy and outboard motor on the swim platform, full chain anchor with windlass or no windlass anchor and rope etc. can affect performance.

I’m the second owner of my boat and previous owner had it antifouled from searay factory with petit hydrocoat because it is compulsory with coloured hull. Next season he painted the bottom with awl grip until I bought. When I bought I cleaned the hull and painted with international (interlux in USA) primecon primer and interspeed ultra black antifouling whis is for extra fouled water, hard formula and long term durability for planing hull and 25 knot speed. This is my third season and every season when I haul out my boat I touch up two coats to bottom.

If you are getting 34knots (with gps not pitot) at 3600-3700 rpm you must have C4 prop set and you’ll reach 36+ knots at 3900/wot. I’d say keep C4 set.

Unlike mercruiser’s rev limiter VP’s EDC has not rev limiter function. I was exceeding 4000 rpm at wot with C3 set like I was hitting 4300rpm.(never tried it once again except first time for a few seconds).

The pdf link you gave is not English and I could only understand just the numbers and graphs. That boat should have C4 prop set with KAD300 for better speed and consumption. Aldo G8 props are too big, they put it to get very high top end speed and wanted to sell diesel engine in that boat to show it is cheaper and faster to run than petrol engine versions.

My last boat was a replica of 2006 275 sundancer, produced by the importer of searay of my country. We put VP D4-210-DPH engine and first put G8 prop set. Engine couldn’t pass 3000-3050 rpm while must hit 3500. Then we swapped with G6 and hit 3400rpm, later put G5 and got 3500rpm. In all prop sets I tried planning speed and wot(almost) were same but consumption was best with G5.

Let us show your beautiful boat and how KAD300 lays in your engine room.

 

[Lord Farringdon]

Hi clasg and good to hear from you again Sayat (Melida). Let's see, Richard, Melida, me and now clasg with excellent tech support from Old Skool, we are getting quite a little KAD 300 group going :smt038

With your experience clasg I won't tell you to 'suck eggs' but given your KAD is operating normally and you don't have sherwood Forest growing on your keel, then props and load configuration are the two main considerations. Personally, my boat jumps out in about 10 -15 seconds depending on where my passengers are seated. Had a couple of heafty fellows on the rear seat the other day with full fuel and water and she lumbered nose high a bit , but she still got up and went in about 15 seconds.

I have C2 props fitted, cruise at 3100 -3200 rpm at 20-21kts and 27-28 kts at WOT. If I had courser pitch props (say C3) I would reach 30 kts WOT but would have some trouble getting out of the hole in a reasonable time under a heavy boat load. On my boat, C2's do the trick.

This prop guide may be of help. http://www.powerproductsystems.com/volvo-prop-guide.asp

Terry

 

[melida]

Hi Terry,
Good to hear from you again.
I think the season is ended and is it winter there ?
Take care.

 

[Lord Farringdon]

Yes, it is winter indeed. This doesn't normally stop us going out as there are usually some really nice winter days that are flat calm. Jun, Jul and Aug are our official Winter months but the temperatures on average don't get below 9 degs C and on nice winter days with flat calm seas can be as high as 15 degs C making for some very pleasant boating. Unfortunately, this winter has brought continuous strong winds and rough seas, so we haven't been out for over two months now. Rosemary and I are padding around the house with upside down smiles.:smt089

Terry

 

[melida]

Too sad for you.
Even the almost entire Europe is having the coldest and windy summer ever we are burning hear lowest 32C highest 37C plus 90% humidity. I had the perfect june and july this year in my 18 years of boating. Very flat seas and once or twice windy days in total of 60 days.
I think the seasons changed due to global warming.
Hope you'll have some sunny days and flat seas left over from summer.

 

[Lord Farringdon]

Thanks Sayat, looks like the wind might drop enough tomorrow so we intend to stick our nose out of the marina and see what it is like. Wish us luck

Terry

 

[Clasg]

Well, well,well......finally came some nice weater this tuesday (so far it has been bad weather with, rain, strong wind and heavy seas) all summer.
I found out that I have C6 propellers on my boat !!
No wonder it could'nt accelerate properly

I have the old B5 aluminium propellers from the former owner, and I mounted them instead ( the boat in the water and me on the platform with a very firm grip on the tools yesterday.
Unfortunately the weather changed again before I could test the new setup properly.
The seas were too rough for WOT but aceleration was some better but still not good enough in my opinion. I reached 32 knots without trouble, but I didn't get the chance to read the tachometer. The boat was very lively at that moment.
So now I will wait for better weather and then do some longer tests.

The hull is clean as a baby's buttom, Terry, and the engine spins like a cat (NOT a CATarpillar
I stille believe it's a great set, but the right set of propelles are needed.
The guide You posted is great, I haven't seen it before. It's better than the official VP propellers guide

Some pictures from the engine room. Not much space for a big guy like me to jump around down there
View attachment 21081
View attachment 21080
View attachment 21079
View attachment 21078
View attachment 21077

 

[melida]

Good to hear from you again.
C6 ? they are too big, but gives higher top end. If you are cruising always single or two people than keep them on, but more than two and full tanks, head sea and fouled bottom won't plane.
I have C4 SS prop set and if the bottom especially props gets fouled it can't plane. Also 300(335)DAs have C4 set.
The prop guide says "For KAD44, 300 engines stainless steel propellers, type C, are recommended" so you should buy C5 set if you felt better with B5 than C6.
By the way I can' see the pics.

 

[Clasg]

Hi Melida

Yes, the pictures are gone... It worked well on my home computer last night, but now I can't see them either.
My guess is, that I uploaded the pictures from my hardisk, instead of as a link to a public server.
I will try again tomorrow :smt001

SS Propellers are very expensive. In Denmark the retail price is 3.400 US $.
On the internet I can find them in US to app. 1.200 US $ + tax + VAT + freight.
Ebay have no second-hand props at the moment.


The alu propellers are not suited for the diesel engines, because of the risk of cavitation.
I read some place about how cavitation can destroy alu propellers in no time.

I mounted the B5 propellers because it's better for the engine, and I thought I could test them, but the weather is really a pain in the a.. this summer.
I will try to contact a VP dealer, to see if he is willing to change my C6 propellers, if possible.
I hpope I can find a dealer that will allow me to test C4 as well as C5 before buying.
We are normally 2-4 people onboard + scuba gear + all the other necessary gear.

My boat is in a harbour app. 60 km from where I live, so I only have a chance to sail in week-ends.
Holiday is over :smt089

Best regards from Denmark :smt038

 

[melida]

Clasg,
Hi again.

As many members (including me) uses photobucket.com for uploading pics then copy pasting the link of the pic. Easier and not decreasing your attachement quota of this site.

As I mentioned in my previous posts I bought C3 props, online from USA and sent it to me with 1/3 price of my country, it was 3500 € + vat 18%. If you decide to use C3 set I can send them.

I can’t argue with you about the alu vs SS props as you are an engineer which I wanted to be a mechanical engineer but couldn’t get the score for it became an economist. I can tell you till morning how will be the € and who is next after Greece, Italy and Portugal.:smt101

I looked to the Searay site for prop chart and it says C6 for your boat. But that’s for an almost empty boat and doesn’t aplly in real life.

It is a pita job to swap the props while the boat in the water. I had to do it last two seasons for zinc replacement. Unfortunately to replace the leg zinc we have to disassemble the props and it is difficult to do it in the water.

For your cruising style C5 seems more suitable for you. Or if you like to benefit of having C6 and faster cruising speed you may enlarge the trim tabs.

Being 60km far from my boat seems to me the other side of the world. In summer it is just front of my house and in winter it is 5km’s from both my home and office.:grin:

Having a boat is an incurable addiction and you must get the right dosage of boat by being near to it.:smt038

Ps: this thread is useless without pix

 

[Clasg]

Hi Melida

Thanks a lot for the offer, but 3.500 EURO sounds like a mistake?

I will try again with some pictures:
As You can see, there ain't much space between deck and engine top
I will try again tomorrow to test the boat properly.

 

[melida]

Clasg,
Hi again.

The most expensive country for its citizens is Turkey. We pay for the world’s most expensive gas, diesel, phone, cell phone, internet etc and very high import fees for imported goods. So don’t believe what you heard about our perfect economic numbers and 17th great economy of the world. Just in a week our money lost 10% value vs dollar euro and gold, and accordingly almost everythings price increased, so it’s normal for 3500Euro+vat for props. I bought them two years ago total cost for 1400$ which was equal to 1000Euros that day. Only used for 30 hours and stayed 6 months on the boat.

The inside of your boat seem almost new for a 2003 model boat, what was the engine hours when you bought it ?

Your engine seems barely fitting in the engine room, is there any burnt or over heated, deformed part of the engine hatch insulation material? Also you need to run the blower longer to cool down the engine room temp.

What’s that black box (like an accu. box) having a blower hose routed upwards between the holding tank and vacuum generator? Do you have a bow thruster and it’s dedicated for it?

One other thing wanted to share is, this year I did changed the four belts and have done the valve clearances besides cleaning all heat exchangers and kompressor. Don’t know which helped but I gained 1-2 knots for cruising. Also your antifreeze expansion tanks seem lower than MIN you should add some.

Have fun with your beautiful boat and monster under the hatch.

 

[Lord Farringdon]

Hi Clasg,

I think Sea Ray must automatically put C6's on these boats and then push them out the factory door. Mine had C6's on it as well but when sea trialled by the agents in NZ these were immediately swapped out for C2's. Under the C6's it wasn't reaching WOT of 3900 and I suspect it was having problems getting out of the hole. Having said that, if a gas engine was fitted (which most of these boats have in the US), a C6 might have been fine. Maybe that's why they come with C6's standard? Anyway, as Melida says, it really all depends on how you use the boat. I would probably do better with C3's. I'd get out of the hole a little slower with full tanks and water but I'd sit on the plane at a lower RPM and get better fuel economy. I'd like to try C3's but as you say, a set of SS duo props is $$$$$! I'd need to save a lot diesel to justify their expense. In your situation though it is about boat perfomance which you currently don't seem to have. You may have to bite the bullet and buy the props. I too have heard that aluminium props don't go well on these engines. I've seen the proof. I was looking around our marina boat yard one day and found a KAD 44 with heavily cavitated aluminium props. He didn't seem to be changing them either before putting the boat back in the water. So, if you want your investment to perform as it should, my suggestion is you talk to your dealer, tell him you'll buy a set of SS props off him, but can he help with some trials of different sizes in order to get the right ones.

Thanks for the pictures. You sure don't have a lot of room in your engine bay but you are still better off than Richard with two KAD 300's! He has some real access problems. Here are some comparitive shots of firstly Richards engine bay and then mine. And yes Sayat, I'm a little low on coolant but it does expand when the engine gets hot. :grin: You'll note I don't have the drive belt protection guard fitted. I like to be able to IR my thermostat housing from time to time. Sayat,please post pictures of your engine bay :grin:

All the best guys


Terry

 

[Clasg]

Holy smoke, there ain't much room in that engine room.:grin:

But nice pair of engines though.

Melida:
The "black box" is an air heater for the cabin. In denmark we have quite cold evenings and nights in autumn and spring, so its really "nice to have" :smt038
And as Terry says, the level in the expansion tank is just above low level, but will rise when engine warms up. Nevertheless, I keep an eye on that tank ..you know "just in case" :smt001
The engine had 320 hours on the clock when I bought it 2 months ago. And now the counter says 340 hours.

There are no sings of burning or overheating in the insulation. I have the samt thought as You about this, but so far no problems. The blower runs continiously until we are docked properly.

Today was a perfect day of testing the boat, so my son and I went to the harbour for some nice boating. The water was totally blank, the sun in the sky and NO wind at all :lol:
Acceleration: 0-20 knots app. 20 seconds
WOT: 3800 rpm = 34 knots
March : 24 knots at 3000 rpm
Weight: Tanks were 3/4 full and me and my son (8 years old) onboard.

I definately have to try C5 propellers.
Sorry, Melida, but C3 would be too small for me. But thanks for the offer anyway.

 

[melida]

Holy smoke, there ain't much room in that engine room.:grin:

But nice pair of engines though.

Melida:
The "black box" is an air heater for the cabin. In denmark we have quite cold evenings and nights in autumn and spring, so its really "nice to have" :smt038
And as Terry says, the level in the expansion tank is just above low level, but will rise when engine warms up. Nevertheless, I keep an eye on that tank ..you know "just in case" :smt001
The engine had 320 hours on the clock when I bought it 2 months ago. And now the counter says 340 hours.

There are no sings of burning or overheating in the insulation. I have the samt thought as You about this, but so far no problems. The blower runs continiously until we are docked properly.

Today was a perfect day of testing the boat, so my son and I went to the harbour for some nice boating. The water was totally blank, the sun in the sky and NO wind at all :lol:
Acceleration: 0-20 knots app. 20 seconds
WOT: 3800 rpm = 34 knots
March : 24 knots at 3000 rpm
Weight: Tanks were 3/4 full and me and my son (8 years old) onboard.

I definately have to try C5 propellers.
Sorry, Melida, but C3 would be too small for me. But thanks for the offer anyway.

ClasG,
It's a good thing having a cabin heater. I have hydronic heating gets the heat of engine's hot water outlet, both for water heater and cabin heater.
I see no water heater in your engine room. Is it fit front of engine or it is dissasambled and should be port aft of engine room where seem epty in your engine room ?
320-340 hours is nothing for a diesel boat unless maintaned well. I bought mine at 135 in feb 2009 and it is 378 today.
Cruising at 3000 rpm is best for this engine, it is the lowest available rpm for max torque and 24 knots is perfect. Also 3500rpm is max rpm for max torque and it is recommended max continous rpm. What did you saw at 3500?
With C5 I don't think you'll loose speed but your consumption will lower and faster planning.

 

[melida]

Hi Clasg,I think Sea Ray must automatically put C6's on these boats and then push them out the factory door. Mine had C6's on it as well but when sea trialled by the agents in NZ these were immediately swapped out for C2's. Under the C6's it wasn't reaching WOT of 3900 and I suspect it was having problems getting out of the hole. Having said that, if a gas engine was fitted (which most of these boats have in the US), a C6 might have been fine. Maybe that's why they come with C6's standard? Anyway, as Melida says, it really all depends on how you use the boat. I would probably do better with C3's. I'd get out of the hole a little slower with full tanks and water but I'd sit on the plane at a lower RPM and get better fuel economy. I'd like to try C3's but as you say, a set of SS duo props is $$$$$! I'd need to save a lot diesel to justify their expense. In your situation though it is about boat perfomance which you currently don't seem to have. You may have to bite the bullet and buy the props. I too have heard that aluminium props don't go well on these engines. I've seen the proof. I was looking around our marina boat yard one day and found a KAD 44 with heavily cavitated aluminium props. He didn't seem to be changing them either before putting the boat back in the water. So, if you want your investment to perform as it should, my suggestion is you talk to your dealer, tell him you'll buy a set of SS props off him, but can he help with some trials of different sizes in order to get the right ones. Thanks for the pictures. You sure don't have a lot of room in your engine bay but you are still better off than Richard with two KAD 300's! He has some real access problems. Here are some comparitive shots of firstly Richards engine bay and then mine. And yes Sayat, I'm a little low on coolant but it does expand when the engine gets hot. :grin: You'll note I don't have the drive belt protection guard fitted. I like to be able to IR my thermostat housing from time to time. Sayat,please post pictures of your engine bay :grin:

All the best guysTerry

These were from last year maintenance.

I can sit between water heater and batteries and can comfortably drain the racor separator/change the fine filter and purge the last chance filter. Also can fit starboard side engine for cleaning AC filter.More pic will come.

 

[Clasg]

Melida:
The water heater is placed in front of the engine room just to the port side of the cold water tank.
Is it a 12V/220V converter You have in that place? (just to the right/front side of your batteries?)
At 3500 rpm I'll guess the speed will be app. 27-29 knots (just a guess though).

When reaching max. speed after trimming (trimmeter says +2 to +3) the boat starts to go up and down faster and faster, like sailing in big waves, even the water is blank. (can't remember the name of this phenomenon, it's NOT chinewalking which is sideways movements).
Anybody who had that experience ?

I have to trim down, which also means loss of max.speed.

 

[Clasg]

Damn'd (sorry the french language .......now I again get loggged out, before I have posted my (maybe too long) reply.:smt021

Is there a feature, where I can adjust the time before automatic logout hits me?