Jump to content

How to find the HP of your engine?

BrenMyster

By BrenMyster
in General Boating

 Share

Featured Posts

Sea Dog Veteran II

Sea DogDonate to Canal World

Posted
Posted (edited)

Hey folks

 

I'm trying to find out the HP of my boats engine for insurance purposes but can't for the life of me see anywhere on the engine where it is written.

 

Any idea how i can find this out?

 

ta

 

You bought a boat without knowing that? How did you ascertain whether it was a good match for the hull and your intended usage?

 

If you can supply the make and model as asked by Dave P, someone here will be able to supply the HP rating, which will be good for the above as well as your insurance company's needs. There's a lot of good engine knowledge on here, so try posting a photo if you aren't sure what you've got.

 

 

Edited to add: I tried Canalplan, which might have shown your engine rating, but there doesn't seem to be any vessels registered on CRT or EA waters under you boat name of Brendan Cleaves.

Edited by Sea Dog
Link to comment
Share on other sites
Alan de Enfield Veteran II

Alan de Enfield

Posted
Posted

I'm going down to it later, Ive got it all the details written down so ill dig out the engine make and model then smile.png

Just found it on Canalplan, dint know that listed boats. All good. smile.png

 

If you cannot find it then you can use a formula that works for all naturally aspirated diesel engines.

 

Basically the formula distils down to :

At WoT a diesel engine uses 0.195 litres per HP per hour

 

So, as an example if you are using 4 litres per hour at WoT then you are have a 20Hp engine.

Link to comment
Share on other sites
ditchcrawler Veteran II

ditchcrawlerDonate to Canal World

Posted
Posted

I'm going down to it later, Ive got it all the details written down so ill dig out the engine make and model then smile.png

Just found it on Canalplan, dint know that listed boats. All good. smile.png

That may not be right

 

If you cannot find it then you can use a formula that works for all naturally aspirated diesel engines.

 

Basically the formula distils down to :

At WoT a diesel engine uses 0.195 litres per HP per hour

 

So, as an example if you are using 4 litres per hour at WoT then you are have a 20Hp engine.

I only use about 1.2 lt per hour but have a 39 hp engine

Link to comment
Share on other sites
Sea Dog Veteran II

Sea DogDonate to Canal World

Posted
Posted

Just found it on Canalplan, dint know that listed boats. All good. :)

Excellent! There is a possibility it's not right as DC says above , but it's an improvement on where you were so I'm glad that was helpful.

 

(I'm guessing the 'boat name' you had displayed and have now removed wasn't your boat's name then Bren!) ;)

Link to comment
Share on other sites
dmr Veteran II

dmr

Posted
Posted

Do you know the capacity (litres) of your engine and its maximum speed on the rev counter? If so I will make a good guess at your horsepower.

 

Assuming its a narrowboat the insurance company does not really care, they are just thinking about high powered speedboats when they ask the horsepower question.

Link to comment
Share on other sites
Alan de Enfield Veteran II

Alan de Enfield

Posted
Posted

Is anybody

 

But, if you do, just the once, you can plot a graph of fuel consumption at various revs, and you will learn a lot about your engine.

 

Consumption = C x RPM3

Where C = Max Fuel Consumption at WOT / RPM3

(Take revs as ‘single figures’ ie 2000 rpm as 2.0, & 2600 rpm as 2.6)

For Ford 2725E engine Max fuel is 28 litres at 2600 rpm

Therefore C = 1.59

At 1000 rpm. 1.59 x 1.03 = 1.6 litres per hour

At 1100 rpm 1.59 x 1.13 = 2.1 litres per hour

At 1200 rpm 1.59 x 1.23 = 2.7 litres per hour

At 1300 rpm 1.59 x 1.33 = 3.5 litres per hour

At 1400 rpm 1.59 x 1.43 = 4.4 litres per hour

At 1500 rpm 1.59 x 1.53 = 5.4 litres per hour

At 1600 rpm 1.59 x 1.63 = 6.5 litres per hour

At 1700 rpm 1.59 x 1.73 = 7.8 litres per hour

At 1800 rpm 1.59 x 1.83 = 9.3 litres per hour

At 1900 rpm 1.59 x 1.93 = 10.9 litres per hour

At 2000 rpm 1.59 x 2.03 = 12.7 litres per hour

At 2100 rpm 1.59 x 2.13 = 14.7 litres per hour

At 2200 rpm 1.59 x 2.23 = 16.9 litres per hour

At 2300 rpm 1.59 x 2.33 = 19.3 litres per hour

At 2400 rpm 1.59 x 2.43 = 22.0 litres per hour

At 2500 rpm 1.59 x 2.53 = 24.8 litres per hour

At 2600 rpm 1.59 x 2.63 = 28.0 litres per hour

 

I have a 2800 litre fuel tank (1x 1000 & 2x 900) so I can now cruise at most economical speeds and get the best 'distance'.

 

At 5 knots, (1500RPM) with 2 engines I am using about 10-11 litres per hour, or 2 litres per Nm, therefore my theoretical 'range' is 1400 Nm.

 

Link to comment
Share on other sites
mross Influencer

mross

Posted
Posted

 

A pedant moment.... only petrols have a throttle, "Full Rack" if you please!

 

...............Dave

I think speed lever would be better, the fuel rack is not what you put your hand on (normally). Even most petrol engines are not throttle controlled nowadays.

 

I'm even more pedantic than you ;-)

Link to comment
Share on other sites
ditchcrawler Veteran II

ditchcrawlerDonate to Canal World

Posted
Posted (edited)

 

But, if you do, just the once, you can plot a graph of fuel consumption at various revs, and you will learn a lot about your engine.

 

Consumption = C x RPM3

Where C = Max Fuel Consumption at WOT / RPM3

(Take revs as ‘single figures’ ie 2000 rpm as 2.0, & 2600 rpm as 2.6)

For Ford 2725E engine Max fuel is 28 litres at 2600 rpm

Therefore C = 1.59

At 1000 rpm. 1.59 x 1.03 = 1.6 litres per hour

At 1100 rpm 1.59 x 1.13 = 2.1 litres per hour

At 1200 rpm 1.59 x 1.23 = 2.7 litres per hour

At 1300 rpm 1.59 x 1.33 = 3.5 litres per hour

At 1400 rpm 1.59 x 1.43 = 4.4 litres per hour

At 1500 rpm 1.59 x 1.53 = 5.4 litres per hour

At 1600 rpm 1.59 x 1.63 = 6.5 litres per hour

At 1700 rpm 1.59 x 1.73 = 7.8 litres per hour

At 1800 rpm 1.59 x 1.83 = 9.3 litres per hour

At 1900 rpm 1.59 x 1.93 = 10.9 litres per hour

At 2000 rpm 1.59 x 2.03 = 12.7 litres per hour

At 2100 rpm 1.59 x 2.13 = 14.7 litres per hour

At 2200 rpm 1.59 x 2.23 = 16.9 litres per hour

At 2300 rpm 1.59 x 2.33 = 19.3 litres per hour

At 2400 rpm 1.59 x 2.43 = 22.0 litres per hour

At 2500 rpm 1.59 x 2.53 = 24.8 litres per hour

At 2600 rpm 1.59 x 2.63 = 28.0 litres per hour

 

I have a 2800 litre fuel tank (1x 1000 & 2x 900) so I can now cruise at most economical speeds and get the best 'distance'.

 

At 5 knots, (1500RPM) with 2 engines I am using about 10-11 litres per hour, or 2 litres per Nm, therefore my theoretical 'range' is 1400 Nm.

 

 

That is assuming that your prop is actually absorbing the total horsepower of your engine.

Edit

I would also have to run at maximum power long enough to use sufficient diesel from my tank to be able to measure it accurately, I actually have no idea where I could do that.

Edited by ditchcrawler
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.