Engine Selection for Canal Boats

This table is to be used as a guide only!

• Beta Marine Limited do not accept any responsibility for incorrect engine selection.
• Please use this table as a rough guide to select the engine size you need for your canal boat (both narrow boats and wide beamers).
• This guide is based upon cruising in still water canals at a relaxed engine speed. If you are using flowing rivers and/or tidal estuaries then a slightly larger engine size may be more suitable.
• Most of our canals and rivers in the UK are limited to 4 mph (3.5 knots) and do not need much power to achieve this; however you should consider safety and manoeuvrability where it is preferable to be able to stop your 10 tons to 30 tons of canal boat in its length.
• You should talk to the boat builder (as they should know the boats designed performance) - the propeller specialist can specify a suitable propeller (based upon engine horse power and rpm) - we then supply the required engine. (The recommended propellers detailed below are based upon 3 fixed blades and a 2:1 reduction gearbox).
• Beta Marine Limited do not accept any responsibility for incorrect engine selection.

Beta Engine	Power Output	Narrow Boat		Wide Beam		Propeller	Bow Thruster
Beta 14	13.3 bhp at 3,600 rpm	20' - 25'	6 tons			12” x 8”	6 hp

Beta 16	16 bhp at 3,600 rpm	20' - 30'	7 tons			12” x 8”	6 hp

Beta 20	20 bhp at 3,600 rpm	20' - 35'	8 tons			13” x 8”	6 hp

Beta 25	25 bhp at 3,600 rpm	25' - 40'	10 tons			14” x 8”	6 hp

Beta 30	30 bhp at 3,600 rpm	30' - 40'	12 tons			15” x 9”	6 hp

Beta 38	35 bhp at 2,800 rpm	40' - 50'	14 tons			16” x 10”	6 hp

Beta 43	43 bhp at 2,800 rpm	50' - 70'	18 tons			18” x 12”	6 hp

Beta 50	50 bhp at 2,800 rpm	60' - 70'	18 tons	45' - 50'	22 tons	19” x 12”	6 hp

Beta 60	56 bhp at 2,700 rpm			50' - 55'	22 tons	20” x 12”	10 hp

Beta 75	75 bhp at 2,600 rpm			55' - 60'	28 tons	20” x 14”	10 hp

Beta 90	90 bhp at 2,600 rpm			60' - 70'	28 tons	Please Ask	10 hp

Beta 105	99 bhp at 2,600 rpm			65' - 75'	30 tons	Please Ask	10 hp

Beta 150	147 bhp at 2,800 rpm			70' - 100'	40 tons	Please Ask	10 - 15 hp

JD3 Tug	30 bhp at 1,200 rpm	60' - 70' Tug	18 tons			20" x 20"

With the longer Narrowboats – say 50 to 70 feet on the Inland Waterways, we generally look at two different applications (power requirements):

a) The canal system where it is recommended that you can stop your vessel / boat within a boat length.
b) More the inland river system and estuaries where the tides and rivers can flow at up to 8 knots at different times of the year.

One of our dealers / marine engineers has said the he can go anywhere on the UK canals with a Beta 38; We guess he always allows for the changing tides and does not venture out after heavy rains and fast flowing rivers.

Another experienced marine engineer uses 1hp per foot, and he says that he has never been caught out wanting on engine power. Technically, a propeller specialist states the propeller required and the power required to drive it.

As an engine manufacturer we will always err on the side of caution with a small safety margin (we try to avoid being undersized).