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| Replacing a BMC 1.5 captain engine ? |
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Message |
    
François
Visitor
| | Posted on Tuesday, February 03, 2009 - 04:03 pm: | 
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Hello,
I have a pilot cutter boat à la "Colin Archer" running both sails and a BMC captain engine. It works quite well but I just cannot have it maintained here on the French side of the Channel!
Since the engine is certainly an essential piece in terms of security on this heavy boat, I'm looking for an alternative engine to replace the BMC.
Even better an engine that would fit the seat of my lovely oldish captain. I may be dreaming at this stage
Any idea or pointer on smart replacement? I understand that the captain engine was 1.5liter and rated 30hp but I have no idea about its torque! And there was certainly not too much of torque for the 11 tons of the boat in nasty windy conditions.
Any tip welcome |
oslin04
Member
Username: oslin04
Post Number: 21
Registered: 10-2006
| | Posted on Friday, March 06, 2009 - 01:22 pm: |
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Hi Francois,
The BMC Captain you have is 36 HP, there should not be a great differance in the engine beds for a more modern unit, you might have to pack it up or down but you will be very lucky if another unit fits the existing beds like a glove :-) I would suggest you should be looking at 80 hp for that size vessel.
Regards Keith |
oslin04
Member
Username: oslin04
Post Number: 22
Registered: 10-2006
| | Posted on Friday, March 06, 2009 - 01:26 pm: |
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PS Francois,
You can get all the parts you for the BMC Captain from www.asap-supplies.com and what they do not have they can get for you and send mail order to you in France.
Keith |
murray_m
New member
Username: murray_m
Post Number: 1
Registered: 08-2009
| | Posted on Monday, August 17, 2009 - 11:15 pm: |
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Francois, I would probably look at one of the Yanmar 3JH43. it is similar horse power but in a smaller package. I would be guessing your boat is equipped with a 2 to 1 reduction gearbox.
other options would be the Kubota based Vetus and Nanni diesel units. In all of these you should be able to get the same horsepower in a smaller package. Biggest problem with the style of boat you have would be in the propeller aperture to swing a large enough propeller.
My father had the BMC Captain in a 23ft heavy displacement launch The boat was basically under powered in rough conditions so we decided to change the ratio of the reduction gear from 2 to 1 to a 3 to 1 reduction. Before this change the boat would reach a maximum speed of just over 7 knots, slightly over displacement speed of the vessel with a 16 x 10 inch prop I did the figures and found with the new reduction we would be able to turn a 19 x 15 inch prop but obviously at slower shaft revolutions 1000 prop shaft revolutions as opposed to the 1500 on the 2:1 reduction. The speed increase was more than we expected lift maximum speed to around 7.8knots but performance in a sea way was dramatcally improved with the boat not being slowed so much by wave action. Propeller slip had reduced from 33% to around 25% and this is why the larger propeller was so effective.
With the type of yacht you have it would be unlikely that you would be able to swing as larger propeller as that though. |
jimmy burrows
Visitor
| | Posted on Thursday, March 16, 2017 - 06:09 am: |
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had to remove my 1.5 bmc diesel for repair will a 2.2 fit in its place and can I use my old engine parts to marinise it |
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