Diesel vs Petrol

SouthWales

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An odd question but on balance, when averaging out diesel from the yacht clubs Vs petrol from those station, what turns out cheaper fro travelling in similar conditions?
 

CLB

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Diesel engined boat is always cheaper to run, like for like, and still will be even when red is gone. Availability of petrol is the killer though. While I would happily run a single engined petrol boat, I just cannot get fuel at enough locations in my cruising areas to make it work. Lugging jerry cans from local garages really isn't the answer. I've been there and done that. Never again.
 

graham

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Tesco's garage I s a 10 minute walk from Milford Haven.I have worn out a few pairs of shoes going back and forth. I carry a folding bike and a large rucksack when cruising I carried 3 five liter cans in it at a time.Hard work if you are going miles for it. .useful for shopping as well as fuel. Last year we bought a new boat with a diesel.
 

SouthWales

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Diesel engined boat is always cheaper to run, like for like, and still will be even when red is gone. Availability of petrol is the killer though. While I would happily run a single engined petrol boat, I just cannot get fuel at enough locations in my cruising areas to make it work. Lugging jerry cans from local garages really isn't the answer. I've been there and done that. Never again.

Thank you all for the replies...it sounds like diesel is the way to go on the Bristol Channel.

Then comes the safety question - some boats are offered with 1 D6 diesel inboard or twins yamaha/suzuki 175hp petrol outboards.

Are their any safety advantages in having twins? (one single fuelling system in either case mind you, we are not considering an Elling or Nordhavn here :) )
 

ontheplane

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It depends on the size of Engine too. A small outboard is fine, but trying to obtain enough petrol to replace that burnt by a couple of 200HP outboards is not practical so you HAVE to be able to fill dockside.

I ran a carb 5.7 in a 26' cruiser about 12 years ago - petrol on the forecourt was well under £1 a litre back then and I got low on fuel in the middle of a run due to a problem with the engine / calculation. I had to head for a port (West Bay) and then had to get a Taxi driver to shuttle me to and fro to the fuel station (2 miles away) - I bought 10 5 litre cans (Taxi driver did raise an eyebrow or 2) and then proceeded to try and fill a 60 gallon tank... took most of the morning, £200 in fuel, £100 taxi bill and so on - just hell.

So small engines petrol is fine, but once up into 100HP plus just gets harder and harder to make it work.....
 

ontheplane

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There are (some) safety advantages with twins - however not as many as some make out.

Whilst it's true that if there is some form of mechanical failure, the second engine should keep going - it's also true that in engine bays of smaller boats, where single and twin's are offered, access to some service items can be tricky so they can be skipped, or replaced badly - hence creating a mechanical failure. Plus of course two engines means twice as many bits TO go wrong so the chance of one engine experiencing an issue is exactly double (or given the above, perhaps even more than double) although this is unlikely to stop the boat.

You'd be mad to buy twin petrol outboards in preference to a single diesel unless the purchase cost was massively different - remember money spent on the boat will be returned upon resale whereas money spent on fuel has literally gone up in smoke.....

Having said that, twin petrol outboards are easy to service, cheap to service and almost 100% reliable if previously serviced so they are the most reliable option.

Most likely to give you grief is contaminated fuel - Small boats frequently draw the fuel from both engines from one tank - so both engines often pack up or struggle at the same time and together - only sure fire way to beat that is to have two independant fuel tanks, and never ever fill both from the same source (even different pumps at the same berth may draw from the same tank thus filling both with contaminated fuel.

Best bet is a series of very good, easy to clean clear bowl filters and separators. Some like a combined filter and water separator, but I'd actually prefer to have separate ones, and in a perfect world, I'd have a coarse filter - then a water separator, and then a separate fine filter on the fuel line meaning that in the event of bad fuel, if it's really nasty stuff, the coarse filter will filter it without blocking, giving some warning what's happening.

The other thing that will stop you is hitting a bank / rock or picking up a line - this may only take out one drive - but there is still a chance to take out both.....

Given Nordhaven's cross the Atlantic with just one engine (and a wing engine to be fair) then it's not so much how many engines, but how they are maintained that's the issue.

Single engine is fine, just maintain it, and have the tender outboard large enough it can be used to "steer" the main vessel if there is a problem. It's unrealistic to expect the tender outboard to "drive the boat" back to base (unless there is no wind or tide which isn't happening ever in the Bristol Channel) but you can use it to point the boat in a direction that will work WITH the wind and tide to get you somewhere safe, or avoid rocks / banks etc until help arrives.
 

SouthWales

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There are (some) safety advantages with twins - however not as many as some make out.

Whilst it's true that if there is some form of mechanical failure, the second engine should keep going - it's also true that in engine bays of smaller boats, where single and twin's are offered, access to some service items can be tricky so they can be skipped, or replaced badly - hence creating a mechanical failure. Plus of course two engines means twice as many bits TO go wrong so the chance of one engine experiencing an issue is exactly double (or given the above, perhaps even more than double) although this is unlikely to stop the boat.

You'd be mad to buy twin petrol outboards in preference to a single diesel unless the purchase cost was massively different - remember money spent on the boat will be returned upon resale whereas money spent on fuel has literally gone up in smoke.....

Having said that, twin petrol outboards are easy to service, cheap to service and almost 100% reliable if previously serviced so they are the most reliable option.

Most likely to give you grief is contaminated fuel - Small boats frequently draw the fuel from both engines from one tank - so both engines often pack up or struggle at the same time and together - only sure fire way to beat that is to have two independant fuel tanks, and never ever fill both from the same source (even different pumps at the same berth may draw from the same tank thus filling both with contaminated fuel.

Best bet is a series of very good, easy to clean clear bowl filters and separators. Some like a combined filter and water separator, but I'd actually prefer to have separate ones, and in a perfect world, I'd have a coarse filter - then a water separator, and then a separate fine filter on the fuel line meaning that in the event of bad fuel, if it's really nasty stuff, the coarse filter will filter it without blocking, giving some warning what's happening.

The other thing that will stop you is hitting a bank / rock or picking up a line - this may only take out one drive - but there is still a chance to take out both.....

Given Nordhaven's cross the Atlantic with just one engine (and a wing engine to be fair) then it's not so much how many engines, but how they are maintained that's the issue.

Single engine is fine, just maintain it, and have the tender outboard large enough it can be used to "steer" the main vessel if there is a problem. It's unrealistic to expect the tender outboard to "drive the boat" back to base (unless there is no wind or tide which isn't happening ever in the Bristol Channel) but you can use it to point the boat in a direction that will work WITH the wind and tide to get you somewhere safe, or avoid rocks / banks etc until help arrives.

This was bookmarked - thanks
 

portis_rich

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Petrol is 135 at Portishead currently, but It was up nearer 150 during the summer. On reflection fuel is a very small fraction of the cost of running my Beneteau Antares 7.80.
 

carlnaj

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Great! how is pricing compared to a supermarket's station?
When I last filled up at the end of November it was roughly £1.23 ish a litre which was about 11/12p over the local sainsbury’s price at the time, that was berth holders price not sure what the visitors price was sorry.
 
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