Outboard or inboard

GARYSJENKINS

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What is needed is a direct comparison using the same boat kad 32 x Suzuki 200hp.Not feasible I guess. If manufacturers claims of this modern petrol fuel burn is correct it balances out fuel costs per litre.
 
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I would say your biggest issue is petrol availability. On a small boat like the ones you mention overall fuel expense isnt going to be that high and the greater fuel consumption of a petrol will be offset by the lower initial cost (if new) and reduced servicing costs. so if you research and find for your needs petrol will work that is clearly the way to go these days with modern high performance outboards.
 

madabouttheboat

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Suzuki 200hp lean burn mag article.
We tested a Suzuki DF200ATX on the back of a 6.3m Tournament 2000 Bluewater fibreglass half cabin. The boat is listed as having a hull weight (dry) of 960kg.
PERFORMANCE - SPEED
3.2kts (6.0km/h) @ 1000rpm
5.0kts (9.2km/h)@ 1500rpm
6.4kts (11.8km/h) @ 2000rpm
7.9kts (14.6km/h) @ 2500rpm
13.5kts (25.0km/h) @ 3000rpm
19.8kts (36.6km/h) @ 3500rpm
24.6kts (45.5km/h) @ 4000rpm
29.2kts (54.0km/h) @ 4500rpm
32.2kts (59.6km/h) @ 5000rpm
36.0kts (66.6km/h) @ 5500rpm
38.6kts (71.4km/h) @ 6000rpm
40.1kts (74.2km/h) @ 6200rpm (WOT)
PERFORMANCE – ECONOMY
2.7 l/ph @ 1000rpm
4.5 l/ph @ 1500rpm
6.1 l/ph @ 2000rpm
10.1 l/ph @ 2500rpm
13.3 l/ph @ 3000rpm
16.9 l/ph @ 3500rpm
23.8 l/ph @ 4000rpm
27.8 l/ph @ 4500rpm
35.4 l/ph @ 5000rpm
41.9 l/ph @ 5500rpm
66.0 l/ph @ 6000rpm
68.8 l/ph @ 6200rpm (WOT)

I think?
Based on the Merry Fisher 790 with a 280l tank and 20% reserve of 56 l leaves 224l @ 1.17 nm per litre = 262 miles for 3000rpm giving 20knots.
Although the 790 is 1.3 mtr longer and heavier than the test boat.


This may help: 795 with 200hp (Yamaha rather than Suzuki, but won't be much in it.)

795.png


I had a 25ft sportscruiser with a KAD32 diesel and used to get circa 5mpg at cruising speed for comparison.
 

GARYSJENKINS

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I work on 30 litres per hour with a kad 32 (170hp) diesel at about 23 kots
Further below post shows the 795 fuel table outboard running at 37 litres @ 23 knots for 4500rpm.Not a large difference. However that same post quotes his 25ft sportcruiser runs 5mpg at cruise speed on his KAD32 (say 23 knots?) but the 795 ruturns only 2.8 mpg. A large difference.
Thanks for both posts giving real world fuel burn on your boats. A real world post from a outboard 200hp owner running a sportcruiser would truly clarify.
 

ontheplane

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What is needed is a direct comparison using the same boat kad 32 x Suzuki 200hp.Not feasible I guess. If manufacturers claims of this modern petrol fuel burn is correct it balances out fuel costs per litre.

Closest you will get to that is THIS

3 identical boats, outboard, stendrive and diesel sterndrive.

It showed the outboard to be quicker accelerating, and easier to service, but the diesel burned about half the fuel at cruise. Of course this means cheaper fuel and longer range + fuel availability - whether that out weighs cheaper servicing and access.... plus there is initial purchase to consider. (But money on fuel is up in smoke, money in boat by and large stays at resale)


This debate ran at huge length here too in the end... Mercury V12 600hp Verado Outboard Engine
 

C08

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What about the comparive cost to buy a new 200hp outboard compared to a similar sized diesel. I know the purchase cost of big outboards is eyewatering are diesels the same?
 

Bouba

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In the Mediterranean, older design outboard boats meant that stern to mooring was difficult and you lost that most vital part of the boat, the swim platform. But new modern boat designs have completely cured those problems
 

Bouba

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I've recently sold one with a 425hp Cummins and bought one with 2 x 300hp Yamahas ... I don't work out the fuel consumption figures or work out the cost - just shut my eyes, fill it up and stick the cc in the machine! I prefer to enjoy my boating! ... ?
Did you also slightly upgrade your name a little (by one)?
 

Plum

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So that is one downside I had not considered. Lack of petrol in marina's. What is the cost comparison white diesel and petrol as red I hear is coming to a end for leisure use. Are the fuel burn differences the reason for doubling costs on longer trips?

Petrol available on Suffolk, Essex, Kent coast from East Coast Pilot book.
Suffolk Yacht Harbour, River Orwell
Bradwell Marina, Blackwater
Essex Marina, Crouch
Gillingham Marina, Medway
Chatham Maratime Marina, Medway
Ramsgate

Not sure what is available on the Norfolk Broads or Upper Thames?

Merry Fisher has 280 litre tank
(a forum on Norfolk Broads quotes 3 litres per hr @ 5mph for his 200hp)

Cant find anything north of River Orwell when we want to cruise the Broads coming up from the Crouch. Any thoughts?
If you are still considering petrol and relying on that list of available sources, I suggest you check Bradwell. Yes, they have petrol, but the pump is not on the pontoon, it's in the yard and I've only seen it used to fill boats on trailers before launching.

I was on the Broads in 2019 and don't recall seeing any waterside petrol pumps. Finding Diesel was not easy!

Www.solocoastalsailing.co.uk
 

GARYSJENKINS

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If you are still considering petrol and relying on that list of available sources, I suggest you check Bradwell. Yes, they have petrol, but the pump is not on the pontoon, it's in the yard and I've only seen it used to fill boats on trailers before launching.

I was on the Broads in 2019 and don't recall seeing any waterside petrol pumps. Finding Diesel was not easy!

Www.solocoastalsailing.co.uk
Thanks, I am probably going diesel after many similar comments. Helps that red is still available in future. Something like a Beneteau Series 9 fits the bill for longer term cruising. We don't fish so would adapt the rear to a seating area.
 

Hot Property

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Further below post shows the 795 fuel table outboard running at 37 litres @ 23 knots for 4500rpm.Not a large difference. However that same post quotes his 25ft sportcruiser runs 5mpg at cruise speed on his KAD32 (say 23 knots?) but the 795 ruturns only 2.8 mpg. A large difference.
Thanks for both posts giving real world fuel burn on your boats. A real world post from a outboard 200hp owner running a sportcruiser would truly clarify.

Here comes the real world then.....

23 ft sports cruiser. All up weight around 2.2 tons, ( boat 1700 , engine 300 plus 200 kg of bits.).

Verado 200 supercharged engine. Gen 1 so not as fuel efficient as the later ones but not a lot in it.

Displacement speed 5 knots I use about 5 litre/ HR.

Cruising on the plane 20 knots at 4,000 rpm uses 30 litres/ HR. About 3 mpg.

210 litre tank so 140 miles theoretical range.

Safely went from Hamble to Brixham on a tank with some reserve.

Outboards are MUCH cheaper to service. Outdrives are the work of the devil in my view!

I had a lift and hold last week and pressure washed hull and oil changes etc. Done in a few hours....

Fuel does cost more but my berth costs even more at £2k. If I use the boat for 50 hours in a season then I will use about 1200 litres with mixed boating. I will have had a great season if I'm lucky enough to spend that much!

Diesel wins for cost of fuel but don't underestimate spare parts costs for inboards, plus time in changing belts fuel filters, risers, bellows etc.

I just like to go boating so outboards suit me down to the ground.

As far as stealing outboards go, then good luck lifting a 300 kg deadweight off my transom!

Pm me if you have any specific questions.
 

Bouba

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Here comes the real world then.....

23 ft sports cruiser. All up weight around 2.2 tons, ( boat 1700 , engine 300 plus 200 kg of bits.).

Verado 200 supercharged engine. Gen 1 so not as fuel efficient as the later ones but not a lot in it.

Displacement speed 5 knots I use about 5 litre/ HR.

Cruising on the plane 20 knots at 4,000 rpm uses 30 litres/ HR. About 3 mpg.

210 litre tank so 140 miles theoretical range.

Safely went from Hamble to Brixham on a tank with some reserve.

Outboards are MUCH cheaper to service. Outdrives are the work of the devil in my view!

I had a lift and hold last week and pressure washed hull and oil changes etc. Done in a few hours....

Fuel does cost more but my berth costs even more at £2k. If I use the boat for 50 hours in a season then I will use about 1200 litres with mixed boating. I will have had a great season if I'm lucky enough to spend that much!

Diesel wins for cost of fuel but don't underestimate spare parts costs for inboards, plus time in changing belts fuel filters, risers, bellows etc.

I just like to go boating so outboards suit me down to the ground.

As far as stealing outboards go, then good luck lifting a 300 kg deadweight off my transom!

Pm me if you have any specific questions.
I agree with everything you say. But I’ve had a brand new Honda 150 (223kgs) stolen from my transom. They didn’t even scratch the boat
 

Hot Property

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I agree with everything you say. But I’ve had a brand new Honda 150 (223kgs) stolen from my transom. They didn’t even scratch the boat

That's sad to hear, I had a new HOnda 135 which is similar without the Vtec bit.. Great engine.

I suppose it does depend on where the boat is kept. I have the good fortune in that there is lots of foot fall past the boat with owners and liveaboards in the mix. which act as good security...
 

Bouba

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That's sad to hear, I had a new HOnda 135 which is similar without the Vtec bit.. Great engine.

I suppose it does depend on where the boat is kept. I have the good fortune in that there is lots of foot fall past the boat with owners and liveaboards in the mix. which act as good security...
Yeah, it is a great engine (luckily the dealer replaced it with the meager amount that the insurance company paid out). The boat was kept on a dry stack. The thieves went through the place like it was Supermarket Sweep (I think some 300hp Verados went too)
 
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