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Alchemy
26-11-2009, 05:35 PM
I'm currently researching boat upgrade options, and a big part of this is the power decision. Originally I was going to go with a 300hp Suzuki, but have lately been considering a diesel stern drive.

All my boating experience has been with outboard power, so I am seeking feedback on the pros and cons of the stern drive. Specifically I'd like to hear from those with experience with the Bravo 1, 2 & 3 stern drives. I have spoken to three different people who I know to have much experience in this area, but they each recommended a different option - ie they each suggested the 1, 2 and 3 :-/

Horse power I am looking at is mid 200hp range, boat will be a plately around 7.5m, on trailer, never moored.

Any help would be appreciated.

Thanks,
Dave.

PinHead
26-11-2009, 06:15 PM
I had 2 Volvo 4.3l 225hp stern drives in the last boat..never had any problems with them..very reliable. Ran Volvo legs on them.

siegfried
26-11-2009, 06:36 PM
check out afew Yank sites (hull truth etc) overwhelming majority use volvo , me big fan of penta duo prop, more expensive but imo worth the expense

Wahoo
26-11-2009, 06:45 PM
Dave
you can give Scott (Bluewater boats ) a call as he has done a few and may be able to give you some real feed back.. I think he is on a project now..Im sure he would be more than happy to help you out

cheers
Daz

siegfried
26-11-2009, 07:49 PM
Yep, get advice from a boat builder rather then someone that actually owns one, :P I have a setup that may be right up your alley PM if you want, youll be very happy with a properly set up diesel with the right drive, get it wrong and youll want deep full pockets.

lethal098
26-11-2009, 08:38 PM
i have been using a mates lazercraft and it is powered by a 3.2litre STEYR diesel and i think a bravo 2 leg, it flies and uses very little diesel for the size boat. If you would like to see it pm me and i can arrange a visual and water test and pick Tims brains as his research was long and exhaustive. Cheers Lee

Smithy
26-11-2009, 09:06 PM
Anything Cummins in big boat land is a good thing. Can only think of a couple of dodgey Cummins' but lots of problems with all other brands. Cummins are now in bed with Mercruiser which can only be a good thing if you go that way. Not real sure about the bombed up small capacity things like the Steyrs and Ivecos. They might produce good figures for power and torque but in real life I know of a recently launched Cairns Custom Craft bridgedeck where the 5 cylinder Iveco just didn't have the balls to get it on the plane fully loaded. Once it got over the hump it flew but you still need those balls down low that only CCs can provide. What is the engine life going to be for these souped up small diesels when you compare them to the stress and strain put on big low revving things like Gardners etc. that run forever? Volvo are pissing a few people off at the moment with their parts support and have never been a fan of an engine designed for cold Scandinavian waters when you start running them in TNQ. Big waiting times if things go pear shaped.

captain rednut
26-11-2009, 09:21 PM
hi i can recommend yanmar/ bravo 2 engine packages to suit your size platey. the 315hp is my favourite. cheers jim

Crocodile
27-11-2009, 07:17 AM
Hello Alchemy,
How many hours a year will you put on this rig?
If it is less than about a thousand fit an outboard.
A diesel in this range will be $15-20K dearer than an outboard, you will never recover the extra cost in fuel savings.
Have a read of the Seamedia test of the Quintrex 670 Offshore/Diesel.
Peter Webster says that for recreational usage the diesel is "just all wrong".
http://www.seamedia.com.au/sea_library/boats.php
If you a concerned about fire, maybe, but how many outboards burn?, not many.

Noelm
27-11-2009, 08:15 AM
that may be true, but there is a host of advantages in having a diesel in a boat, not just fuel savings, a few are, saftey with fuel carried, not too many worry about turning the ignition key with diesel, not real problems with a wet motor, definately no ignition probelms, able to run accessories not available with outboard power, and limited with petrol , like as in Hydraulic power and pumps, even air conditioning, genset, all sorts of stuff, but there is a trade off, price and weight

Noelm
27-11-2009, 08:19 AM
I forgot to add, and this is only my opinon! I reckon stern drives are kind of the ugly cousin, for me, it is outboard or shaft drive, stern drives to me seem to have the two biggest bugs of a small boat, they take up space in the boat, plus they have a leg out the back as well, with an outboard you only get the out the back problem, and shaft drive, only the in the boat space problem.

Crocodile
27-11-2009, 08:28 AM
Hello Noelm,

most of what you say is correct, except for the wet engine.
Modern electronic diesels have electronic injection systems that are just a susceptible to water as any injected petrol engine. They also have an electric starter motor that lives in a humid bilge, I don't think that you can hand crank a 200hp diesel.

Noelm
27-11-2009, 08:30 AM
yep, for sure, but if getting wet is an issue, I would rather a diesel in water than a petrol, but you are correct.

lethal098
27-11-2009, 08:30 AM
SMITHY,
Yes the cummins are a good motor but once you see the figures of the Steyr and the build quality of the engine they are near indestructible, i had never really heard of them until my mate had one put into his. Speak to anyone that has been in it and no one can believe what she performs like.

Having the diesel in the boat gives you a much lower centre of gravity and therefore in most boats a much better ride. The comments i have had have been like you are riding in a 30+ foot cruiser. I had Mark Jones onboard the other week and you can read his comments in one of my previous reports of river to reef. The boat can top out at 45 knots so performance is unquestionable.

cheers Lee

Noelm
27-11-2009, 08:36 AM
just sort of thinking, I have brought this up before with motor like the Subaru, I wonder why they have not put much development into flat (horizontaly apposed) like the Mercedes used in buses? it would seem like a win win situation to be able to produce a very low profile engine, not just for smaller boats that would leave an almost flat floor, but in bigger boats where you could lower the centre of gravity even more with a flat diesel. I did a bit of work on one in a bus for a mate of mine and thought it was a dream engine to do anything to, most stuff was very easy to access, especially seeing as the floor of the bus just lifted off, exposing the engine.

firstlight
27-11-2009, 08:36 AM
Hi Alchemy, have a look at the Lombardini's with a mercruise leg, a mate is looking at putting one in a 7m platy as aposed to a 250hp outboard. he's looking at a 5 cylinder diesel Lombardini, 197hp or maybe this was the kilowatts equivalent. I think from memory the hull drag and torque modelling showed something like 8.3 L/Hr at 20knotts cruise speed. the package was $16.500 plus installation in comparison to outboard cost of around $25k.

hope this helps mate

cheers
firstlight

lethal098
27-11-2009, 10:49 AM
noelm,

yeah i like that idea, a nice 2.5litre wrx engine would be a killer, maybe someone should give it a go.

cheers Lee

Crocodile
27-11-2009, 12:43 PM
Hello Noelm,
Yes, Perkins used to make straight sixes that lay on their side.
Would be good as it allows the wheelhouse to be lower.
It also lowers the cylinders to the point that they may be below the waterline, you would need very good risers etc. on the exhaust to stop water getting back into the cylinders.
Hello Firstlight,
8.3 L/Hr at 20knotts cruise in a 7m boat would not be correct.
refer to Seamedia
7.5m Riptide/190Volvo 21knots 19lt/hr
7.2m Plate cruiser(heavy)/240hp Yanmar 22knots 32lt/hr
########.com
25 ft Doral Express Cruiser/260 Yanmar 25knot 26lt/hr
Also a diesel sterndrive for $16K would be the bargain of the century.

PADDLES
27-11-2009, 01:32 PM
if you do a quick web search, track down an article in "popular mechanics" that compares mercruiser diesel/petrol powerplants of similar output in identical searay sundancers. like has been said, you'll need to do a heap of hours to get the money back. a petrol sterndrive for $16k would be a bargain, let alone a diesel!

brrbear
27-11-2009, 06:18 PM
Hi Alchemy, have a look at the Lombardini's with a mercruise leg, a mate is looking at putting one in a 7m platy as aposed to a 250hp outboard. he's looking at a 5 cylinder diesel Lombardini, 197hp or maybe this was the kilowatts equivalent. I think from memory the hull drag and torque modelling showed something like 8.3 L/Hr at 20knotts cruise speed. the package was $16.500 plus installation in comparison to outboard cost of around $25k.

hope this helps mate

cheers
firstlight


where from??? 16.5k for new diesel and leg?

firstlight
27-11-2009, 07:00 PM
Sorry if i've given anyone a bum steer, try google Lombardini diesel marine should help. Inboards are not my preferred choice in powering a boat but then i don't own one big enought to justify (6.2 Fisher - 175 suzi). may have my wires crossed on hp/ price/ kilowatts but all other info is as told to me and i too was impressed, just trying to help mate. I will follow up on more info and stand corrected if wrong. whip me baby whip me. :) :o :)

cheers
firstlight

Alchemy
27-11-2009, 09:38 PM
Anything Cummins in big boat land is a good thing. Can only think of a couple of dodgey Cummins' but lots of problems with all other brands. Cummins are now in bed with Mercruiser which can only be a good thing if you go that way. Not real sure about the bombed up small capacity things like the Steyrs and Ivecos. They might produce good figures for power and torque but in real life I know of a recently launched Cairns Custom Craft bridgedeck where the 5 cylinder Iveco just didn't have the balls to get it on the plane fully loaded. Once it got over the hump it flew but you still need those balls down low that only CCs can provide. What is the engine life going to be for these souped up small diesels when you compare them to the stress and strain put on big low revving things like Gardners etc. that run forever? Volvo are pissing a few people off at the moment with their parts support and have never been a fan of an engine designed for cold Scandinavian waters when you start running them in TNQ. Big waiting times if things go pear shaped.

Thanks Smithy. As a matter of interest what size was the CCC and what horsepower, size engine did it have?


hi i can recommend yanmar/ bravo 2 engine packages to suit your size platey. the 315hp is my favourite. cheers jim

Thanks Jim. Any particular reason you recommend the Bravo 2? Is it somehow better or more suited to this application than the B1 or 3?



that may be true, but there is a host of advantages in having a diesel in a boat, not just fuel savings, a few are, saftey with fuel carried, not too many worry about turning the ignition key with diesel, not real problems with a wet motor, definately no ignition probelms, able to run accessories not available with outboard power, and limited with petrol , like as in Hydraulic power and pumps, even air conditioning, genset, all sorts of stuff, but there is a trade off, price and weight

Thanks Noel. Yeap, lots of pros and cons. One of the additionss I have in mind for down the track is a compressor on the side of the engine coupled to a eutectic tank in my fish box.


I forgot to add, and this is only my opinon! I reckon stern drives are kind of the ugly cousin, for me, it is outboard or shaft drive, stern drives to me seem to have the two biggest bugs of a small boat, they take up space in the boat, plus they have a leg out the back as well, with an outboard you only get the out the back problem, and shaft drive, only the in the boat space problem.

Depending on the transom set up, the intrusion doesn't have to be that great. Eg, my current boat has a 600mm wide area behind the transom (hull extension). The transom is about 300mm wide, so that gives 900mm in which to hide an engine. Depends what you want. The box could also make a good seat.


Hi Alchemy, have a look at the Lombardini's with a mercruise leg, a mate is looking at putting one in a 7m platy as aposed to a 250hp outboard. he's looking at a 5 cylinder diesel Lombardini, 197hp or maybe this was the kilowatts equivalent. I think from memory the hull drag and torque modelling showed something like 8.3 L/Hr at 20knotts cruise speed. the package was $16.500 plus installation in comparison to outboard cost of around $25k.

hope this helps mate

cheers
firstlight

Thanks Firstlight. I will suss them out. Any idea where he got that price as it sounds too good to be true?

Lee, can I ask why your mate chose the Bravo 2 over other Bravo options?

Thankyou to everyone else who has replied too. As I said earlier, there are many pros and cons with a stern drive set up versus outboard.

What I am most interested in at this point though is feedback from anyone with experience with the Bravo 1,2 &/or 3 stern drive packages.

Regards,
Dave.

Alchemy
27-11-2009, 09:49 PM
if you do a quick web search, track down an article in "popular mechanics" that compares mercruiser diesel/petrol powerplants of similar output in identical searay sundancers. like has been said, you'll need to do a heap of hours to get the money back. a petrol sterndrive for $16k would be a bargain, let alone a diesel!

Thanks Paddles, that was an interesting read. I haven't gone to the extent that they have in working out payback, but if it takes five years, then I'm happy with that!

"The diesel sips half as much fuel as the gas sterndrive, but, at 20 mph, it will take you 22,373 miles to recover the extra initial cost of the diesel engine. At 34.7 mph, it will take 18,719 miles to break even. That's 540 hours of running, which for the average American boater is five summers" http://www.popularmechanics.com/outdoors/adventures/1277216.html?page=3

sleepygreg
27-11-2009, 10:12 PM
re the outboard v sterndrive comparison. The only boats I have been on that enabled me to compare an outboard with a sterndrive was a Vickers easyrider 570. a couple of mates had them. One had a 150hp outboard, and the other had a 140 mercruiser sterndrive. the outboard powered one performed like a very competent 5.7 metre boat, the sterndrive powered one performed like an extremely well performed 7m boat. I think this was mainly due to the lower centre of gravity and the weight of the engine being further forward in the hull. Plus the most comfortable place to sit when the going got rough was on the engine cover.

As for diesel preferences......have always liked cummins and Yanmar...very reliable and proven fish raisers (yes it does make a difference when gamefishing).

Greg

arvor
28-11-2009, 07:19 AM
Thanks Paddles, that was an interesting read. I haven't gone to the extent that they have in working out payback, but if it takes five years, then I'm happy with that!

"The diesel sips half as much fuel as the gas sterndrive, but, at 20 mph, it will take you 22,373 miles to recover the extra initial cost of the diesel engine. At 34.7 mph, it will take 18,719 miles to break even. That's 540 hours of running, which for the average American boater is five summers" http://www.popularmechanics.com/outdoors/adventures/1277216.html?page=3
we left mooloolaba testerday at 0630 fast troll out to the 50 60 mtr line returned at 1230 never stopped and for 24 litres but thats not the only saving.the sound of it you will be doing a fair few hours out there so even modern diesels for your basic 100hr service most people can service themselfs.so thats 2 or 3 services of a large outboard.and i belive that cost at todays rates are outrageous. i would never go back to another outboard .other things i dont miss .fishing over the top of engines and pods.and a govt mandate to have e10 in motor spirit over the next 5 years or so.sorry i cant help on the sterndrive as both my diesel vessels have been shaft drive.

Midnight
28-11-2009, 05:09 PM
Gday,
Gotta be a Volvo with the DPH drive(when you see the drive in the flesh,you will know why) first and Yanmar ZT350 second for me.
Remeber with the Cummins Mercruiser you don't get a true Cummins motor until you get up to the 5.9L, the old 6bta block.
The little ones are VM motors painted white I am told.
Big expense over the outboard though, nearly twice the price plus the servicing, but if you can afford it, a much better sea boat normally results.
Cheers,
Myles

Bertram 25 AQAD41a Volvo with 290 Duoprop leg

lethal098
29-11-2009, 09:59 AM
dave, i will see Tim tomorow and ask him the question and get back to you, cheers Lee

Crocodile
29-11-2009, 10:08 PM
Hello Arvor,
could you be a little more specific please.
How far did you travel, at what speed, and for how long.?
What size boat do you have and what horse motor.?
What is the top speed and crusing speed of your boat.?

PADDLES
30-11-2009, 07:54 AM
g'day crocodile, by the look of arvor's avatar it'll be an arvor. whilst i reckon the arvor's are a good thing, it's not really comparing apples for apples here. the boat is a semi displacement type with a small diesel shaft drive that's not putting out the same power of the stern drive and it won't have the gearbox losses either.

arvor
30-11-2009, 11:03 AM
Hello Arvor,
could you be a little more specific please.
How far did you travel, at what speed, and for how long.?
What size boat do you have and what horse motor.?
What is the top speed and crusing speed of your boat.?
hi croc wellas far as miles travelled unknown.but approx.30 mins at 14 to 16.then maybe 1 hr at 9to11.then 4and a half at 5to 6.5
boat size is 6.1
horsepower is 85
5cyl intercooled small turbo
my top is 18 and cruise is 16
haveing said that there havent been too many times this year that i wanted or needed 30 or 40knots

FNQCairns
30-11-2009, 11:24 AM
You spoke of the 300 Zuk, on one of the fishing shows they refitted a 23 bertram with V8 yamaha from an old mercruiser, did before and after tests.

The upshot outside of the marketing when they showed the graphs was, the V8 in all things except noise was not that much ahead in core power plant areas ie fuel use, cruising speed, top speed and all round performance.

It was a little bit of an eye opener because once when I had a bit to do with stern drives I liked them and was thinking I must have been mistaken given the general direction taken these days when powering.

One thing though I wouldn't choose a petrol over a diesel if I could afford to make it work, these days I think I prefer any boat i am in to have it's petrol engine hanging outside.

cheers fnq

arvor
30-11-2009, 11:27 AM
g'day crocodile, by the look of arvor's avatar it'll be an arvor. whilst i reckon the arvor's are a good thing, it's not really comparing apples for apples here. the boat is a semi displacement type with a small diesel shaft drive that's not putting out the same power of the stern drive and it won't have the gearbox losses either.
hi paddles.i wasnt comparing mine with what alchemy is concidering.mine is a totaly differant design.what i was saying is that a lot of people think its only fuel consumption that is the major factor.but i find that is just one part of it.my serviceing i do it myself and costs between 120 to 150 for parts and 1and a half hours .not dragged an hour to a service place left there for 2 days to a week and charged anywhere 500 to 900 for them big bangers.
other major things .reliability.longevity.centre of gravity.
and i personally just love traditional boating.but each to there own cos there are a lot on here that if it dont do 40 knotts its no good no matter how it handles.
just wish alchemy all the best with the new boat .
gary.

PADDLES
01-12-2009, 08:10 AM
g'day arvor, don't get me wrong mate. like i said, the arvor's are an awesome thing. i was more pointing out that they are just not the same as a diesel sterndrive with leg and so are maybe not a good comparison. they are however a real good alternative to that way of thinking and certainly should be looked at as an option.

servicing is one of those things that's a personal issue. i mean, i'm a bit mechanically minded and could probably do my own servicing, but my boat is a family boat and my family's life depends on it's reliability, so whilst i stay on top of the routine inspection and day to day maintenence, i like to get a professional to cast his eyes over it once a year so that's why i don't service it myself. i figure that he might just see something that i have missed, it's more of an insurance policy really and when you're looking at an investment of towards the $100k mark (of which both our boats are) the $500-$800 a year to service it is a small expense really. just my 10c worth anyway. mind you, with a shaft drive, your servicing should be a whole lot less work than a stern drive leg.