Seapower Marine is Beta Marine’s East Anglian engine supplier and installation specialist.
Since 1998, Seapower Marine has been supplying and installing new Beta Marine engines in a wide range of vessels. From the start, we will take the time to understand what your requirements and expectations of your boat are and ensure that you we help you to choose the right engine for your yacht or motor boat.
1. Choosing your engine – We will assist you with selecting the size of engine you will require for either a displacement hull or sailing yacht. The assumption is that you will wish to reach maximum hull speed and require a suitable engine to achieve this. This assumption may not be correct if you have a racing yacht and only want limited power to reach your moorings; or conversely you do motor sailing with your family and wish a 30 percent safety factor.
We will take these factors into consideration, and if necessary discuss with the boat designer or local boat builer for their recommendations of engine power and propeller size (as theoretically they have specified the boats designed performance / hull speed). We will ensure that you have the correct propeller to achieve the boats designed performance (based upon engine brake horse power and rpm) – only then will we recommend the engine size and supply as agreed.
- A generally accepted rule of thumb for displacement hulls is 4 bhp per ton for cruising yachts
- Maximum hull speed in Knots (for displacement hulls) = 1.3 (or 1.4 for a sleek hull) x √ Water Line length (in feet)
| Engine Size | BHP |
Yacht Displacement – Weight in tonnes |
LWL (water line length) in feet |
| Beta 10 | 10 | 1 – 2 | 22 – 24 |
| Beta 14 | 13.3 | 2 – 3.5 | 24 – 26 |
| Beta 16 | 16 | 3 – 4 | 25 – 28 |
| Beta 20 | 20 | 4 – 5 | 26 – 32 |
| Beta 25 | 25 | 5 – 6 | 27 – 34 |
| Beta 30 | 30 | 6 – 7 | 32 – 36 |
| Beta 35 | 35 | 8 – 9 | 36 – 38 |
| Beta 38 | 38 | 9 – 10 | 37 – 39 |
| Beta 43 | 43 | 10 – 12 | 38 – 42 |
| Beta 50 | 50 | 12 – 15 | 42 – 45 |
| Beta 60 | 56 | 15 – 17 | 43 – 46 |
| Beta 75 | 75 | 17 – 22 | 46 – 50 |
| Beta 90 | 90 | 22 – 24 | 50 – 52 |
| Beta 105 | 99 | 24 – 26 | 51 – 53 |
2. Planning for the installation – We would always recommend that one of our engineers visit you and your boat to make sure that you have chosen the correct engine for your boat. Our engineer will also discuss issues such as, gearbox, control panel options, shaft couplings, engine beds and feet, exhaust options, shafts, pea-brakcets and propellors. Your new engine will not only look clean and shiney but will enhance the value of your boat, that is why our engineer will also talk to about considering items such as new sound insulation. Our attention to detail will ensure that your installation is of the highest standard and your engine room gleam when completed.
3. Proceeding with the purchase/installation – Once your decision is made, we will send you a proforma invoice, (which will require a 10% deposit), your engine will then be ordered. Delivery can take between 2 – 4 weeks, once the engine build is completed, we will agree and delivery and the balance of the invoice will need to be made.
If we are to carry out your installation, we may ask for a pre-payment before the work starts; once the installation has been completed the balance of the installation invoice must be paid in full before leaving any marina or port. Any installation will be estimated and sent to you in writing, which you will need to approve before we start the work. If additional items are required during the installation, we will advise you in writing and require your agreement.