Petrol v. Diesel - Page 2

Rogue Wave · 30 May 2005, 12:01

Quote:

Originally Posted by Solent Ranger

I have a Yamaha 370 sti in my boat. Outstanding 4 cylinder diesel that does not smoke or smell. The unit comes complete with sterndrive. A sterndrive that takes some beating! Silky smooth - no clunking and grinding like you get with Mercs or Volvo sterndrives. I love it! Best peopel to contact are MMS at Eastlands Boat Yard in Swanick & speak to Bill Brown.

I am actually just about to chuck the block from one of these on the Skip if you or anybody else wants it they are welcome....it's surplus to requirements.

I made a mistake (MeMe and Jon Brooks please note). The Hydra drives are fine and yes they are a lovely match for the Yamaha lump! I believe Alan Priddy has an amount of knowledge of Yamahs lumps and Hydradrives also

When I said do Sterndrive make a component for the Yamaha engine I actually meant Sternpower and Yanmar Engine. Sorry if I caused any confusion!. I had a lot on my mind at the time A lot of Brandy that is!

The reputation of the Bravo leg coupled to most Yanmars is not good, it is my undertanding that the company Sternpower make extremely reliable units and was wondering if they had one that coped with the output of the Yanmar.

I can't be bothered to find out as I am unlikely to buy a Yanmar but for those of you that might be

Sternpower Marine Drives Ltd
51 Victoria Rd
Portslade
Brighton
East Sussex, BN41 1XY
Tel: +44 (0) 1273 411765 Fax: +44 (0) 1273 430290

Chris Murray · 30 May 2005, 17:02

Looking at the responses in this thread, it seems like a Yamaha 421 STI (240hp) would be worth considering alongside the Etec 250 outboard.

Does anyone have experience of the relative performance of these two engines on an 8 metre RIB?

My experience of a Yanmar 315 at last year's RIBEX was that the RIB (an 8.5 Scorpion) behaved more like a sports cruiser, in terms of getting onto the plane but once it was going, the engine was quiet (relative to a 225 Optimax).

Whatever boat/engine I buy, I intend to keep it for 15 - 20 years, so life-expectancy of the engine/sterndrive or outboard is an issue. Just for info., I kept my last boat for 14 years from new.

However, I do like a bit of "umph" in the engine, so whilst I may be prepared to compromise a little on the time taken to plane, I still expect performance beyond that.

I now have a 3 litre hi-tech diesel car, which can out-perform a 3.2 litre version of the same car from 0-60 by about a second (Autocar tests - the manufacturer doesn't admit to this!), and has a totally clear exhaust (something to do with the pietzo-electric injectors, I think). I therefore believe that the age of the "clean" diesel has arrived!

MPG is fairly significant too, as I hope to still be running my boat in retirement!

As ever, your thoughts would be most appreciated.

Regards to all,

Chris.

Richard B · 30 May 2005, 17:18

As a rule of thumb, a Yamaha 240hp powered RIB with a deep V should be good for up to 40kts once loaded up. An outboard powered RIB with 250hp will be at least 5, maybe 10kts faster, with a top speed of around 50kts. All this will depend on hull design, fuel load, etc!

Brambles · 30 May 2005, 18:28

Chris,

We had a run from Poole to Yarmouth & back yesterday. We kept the speed down to about 28 knts as we had 3 children on board as well as 3 adults.

The sea was calm and the Etec (according to the fuel flow meter) was using between 8 & 9 gph (UK).

Hope this helps.

Regards.

Ian.

gavin · 30 May 2005, 18:32

Diesel in Ireland has steadily increased, especially since the US and UK began waging war in Afganastain and Iraq, over the past two years .Apart from big Hummers and 14 litre tanks, guzzling the stuff, some of their bikes are also diesel powered, apart from the obvious diesel burners.Extra demand as we know drives up prices economic growth in Asia has all contributed to the rising costs of diesel fuel.You can still run marked or red diesel here in boats, no problem, and no sign of it being phased out or removed as a fuel concession in Ireland , for now.
I posted recently about alternatives to diesel fuel, bio diesel is finding its way onto selected market places in Ireland now, not much of it about yet, as regular road diesel is still pretty cheap at .95 cent euro a litre.
A major consideration when choosing diesel over petrol has to be the cost, not just the running cost but inital coat, diesel powered units being more expensive initally, over petrol outboards.Therefore you have to do the hours , before diesel really becomes economical.
Apart from the economics of it, do you want a sterndrive in the water all the time, on a mooring, or marina, do you want a heavy diesel inboard and outdrive behind you in your 8 m rib in a following sea, will you miss the oomph of a two stroke behind you on take off.
Then of course on cruises and trips you know you will get diesel readily in ports harbours etc, not always so with petrol, I remember coming from Malahide in Dublin to Holyhead and entering the port to refuel with petrol, couldnt get it, nor could we in the town as all 3 petrol stations had closed.We had to buy cans hop in a taxi and head to a Tescos/Sainsburys and fuel up there.
What drive do you fit, do you go Volvo, Bravo, Yamaha.

Its also worth noting that you have to burn a lot of petrol before you match the cost of your inital outlay for a diesel unit, and as I mentioned above Biodiesel, available just about but with little or no quality control in place for it over here for the stuff.

As far as fitting a big Etec is concerned, as with the Evinrude Ficht Rams we had on our Hysucat over 1028 hours between the two motors, same fuel injection technology as ETEC , amazing fuel economy and ultra reliable units, these were only 75hp, not really a fair test but great technology in outboard fuel injection systems , they were excellent, and preceeded Etec, so I can only surmise how good Etec is.

Chris Murray · 30 May 2005, 19:44

Thanks guys for your speedy response.

ONLY 40 kts in an 8 metre RIB - That's FAR TOO SLOW!

It looks like I had better go for the Etec then. Otherwise, I would struggle to keep up with Blue Ice!

After all, a top speed of say 50kts makes 40 kts cruising speed a viable concept. That's Yarmouth to Cherbourg in an hour and a half. It used to take a whole two and a quarter hours in my last boat. OK, so that included a stop for lunch!

I'm off to RIBEX on Friday, as I have yet to decide on the boat itself. At the moment, Excalibur, Ribcraft and Humber look good, although Excalibur is not due to be at the show. I still have an open mind but my budget won't stretch as far as a MK II Scorpion, unless I do without most of the navigation equipment, which is not an option that I am prepared to consider.

Happy RIBing!

Chris.

Searider · 30 May 2005, 21:52

Don't forget the KAD 44 at 260hp.

If you've ever driven a boat with a Volvo KAD engine you need to - when the supercharger cuts in you leave any other diesel boat in your wake.

(Based upon driving both KAD 44 and Yanmar 300 Sunseeker Hawk 34s)

I reckon that the Volvo D6 350 should be a good RIB engine once they sort the fuel pipes and water strainers. 350hp on a sterndrive with a super charger mmm.

Duncan

Quote:

Originally Posted by jwalker

Yeh, that's about right but it'll be the crank power. Volvo drives use up about 12-15hp.

Edit: Just pinched this from Volvo.

.....................prop ....crank ...rpm ...cyls ...capacity
AD41P/DP ......189 ......200 ....3800 ...6 ......3.6
KAD43P/DP .....218 .....230 ....3900 ...6 ......3.6
KAD300/DP-G ..272 .....285 ....3800 ...6 ......3.6

Edit,Edit; WTF! it wus all nicely in line when I wrote it....I think. Typical PC, I thinks it knows best. Anyway, me dots have tricked it.

Richard B · 30 May 2005, 23:14

Quote:

Originally Posted by Chris Murray

...unless I do without most of the navigation equipment, which is not an option that I am prepared to consider.

That's exactly the strategy I would suggest.

You can add electronics later, very easily.

If you decide to upgrade the hull later, that means starting all over again.

Alan · 31 May 2005, 11:06

Quote:

Originally Posted by Chris Murray

After all, a top speed of say 50kts makes 40 kts cruising speed a viable concept. That's Yarmouth to Cherbourg in an hour and a half. It used to take a whole two and a quarter hours in my last boat. OK, so that included a stop for lunch!

IMHO, it'll be a rare day when you cruise at 40kts for any extended period even with a 50kt top end. I used to find that high 30's was good on Blue Ice - the Scorp hull definately rides better than at 20 something unless its really rough. But as you say a high top end gives you high speed cruising options (with the associated high fuel burn of course), which some of the diesel rigs dont.

ADS · 31 May 2005, 11:14

Quote:

Originally Posted by Chris Murray

I now have a 3 litre hi-tech diesel car, which can out-perform a 3.2 litre version of the same car from 0-60 by about a second (Autocar tests - the manufacturer doesn't admit to this!), and has a totally clear exhaust (something to do with the pietzo-electric injectors, I think). I therefore believe that the age of the "clean" diesel has arrived!
Chris.

330d?

[/QUOTE]I have a Yamaha 370 sti in my boat. Outstanding 4 cylinder diesel that does not smoke or smell. The unit comes complete with sterndrive. A sterndrive that takes some beating! Silky smooth - no clunking and grinding like you get with Mercs or Volvo sterndrives. I love it! Best peopel to contact are MMS at Eastlands Boat Yard in Swanick & speak to Bill Brown[/QUOTE]

Did your boat feature in PBO a few years back? If so your most qualified to talk on this subject!

Regards
Alex

Chris Murray · 31 May 2005, 21:06

Sorry Richard - the sums still don't add up!

Besides, I want to know where I'm going from day one! Who said "that'll be a change"?!

Alex - No, it's not a 330d, it's a VW Touareg V6 TDI (3 litre), with low ratio gears, air suspension (adjustable ride height) and 500 nm of torque.

Autocar recorded 0-62 in 9.1 seconds, whereas the 3.2 litre petrol model takes a whole 9.9 seconds!

Not bad for a 2.25-2.5 tonne car!

Yes, I'm sure that the BMW X5 or the 330d would be faster but IMHO they are both lacking in style (inside, at least) and neither can match the comfort or towing ability of my "Treg"! (Oops - I think I'm going to pay for those remarks!)

The only downside is that it takes quite a long time to polish - 10 hours on Sunday! Mind you, I use the Meguiar's polishing system, which is like polishing it three times!

Apologies to JW for going a little "off topic".

Regards,

Chris.