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Outboard Motor Fuel Consumption

Hello, I have been looking to buy a small boat and have seen a 25 footer with an outboard petrol motor, due to this it has only got two small compartments to hold two small gerry can style fuel tank (15 lt each) This does not seem like much, how far can an outboard motor be expected to go on 15 litres of petrol? Thanks

Asked by: Dan Brown  | 4.56pm, Tuesday 8 May

WW says:

Congratulations on looking at a GRP cruiser- its a great way to get afloat and much enjoyment !
The amount of fuel that an outboard motor uses depends very much on the craft it's pushing, the size of the outboard, it's prop diameter and pitch and, most importantly, if it's two or four stroke.
Unless its very very cheap, avoid 2- stroke engines as they use much more fuel and don't like running slowly without oiling up their plugs!
As a rule of thumb, a 10 or 15hp engine will use around 1.5 to 3 litres per hour. On a 20dt cruiser with a 10hp engine I used to use about 1 litre an hour on canals...!
Larger tanks- up to 26 litres- can be bought for use with outboard motors but they must, like all petrol tanks, be stored in accordance with the boat safety scheme- petrol vapour must not be allowed to collect inside the boat. All tanks need to be stored in a ventilated locker or icon a bracket outside the craft. Never refil tanks on tr boat- always move them ashore.
If you can give us the details of the make/ model of boat and engine, we may be able to help you more- but reckon on about 8 to 10 hours cruising per tank of petrol- about one and a half days.

Mark Langley  | 10.19AM, Wednesday 9 May

If you want more advice about specific boats/engines, email me at mark.langley@waterways.com

Mark Langley  | 4.52PM, Wednesday 9 May

The best way to extend the range of a boat with a petrol outboard engine is to have two portable tanks. This avoids the dangerous process of refuelling the tank from jerry cans. When the tank is empty it is a simple matter to swap the bayonet fuel connection over to the new tank, and take the empty tank to the filling station.

Rupert Smedley  | 12.31PM, Thursday 10 May

Readers say:

Hello, thank you very much for the useful information, especially for the storage requirements to meet boat safety, definitely something to think about, thanks.

Dan Brown  | 4.40PM, Wednesday 9 May

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