?derated? engine, what does this mean?

[mat_ryall]

I have a 5hp 1990 Evinrude. Model Number BE5DRLSER. I understand that the ?D? means ?derated?.

The engine is, as far as I can make out, exactly the same as a 6hp model.

Can anyone tell me what modifications may have been done to derate this engine? Is it something simple like a different type of prop?

Cheers

Mat

 

[mat_ryall]

Re: ?derated? engine, what does this mean?

Anyone have any idea?

 

[Chinewalker]

Re: ?derated? engine, what does this mean?

I am pretty sure the only significant difference is they tightened up the gap on the intake reed stops.

 

[mat_ryall]

Re: ?derated? engine, what does this mean?

Thanks for that. The intake manifold part number is the same as that of a 6hp. I guess I could just change the intake reed stops for a 6hp model and that would change it back to a 6hp? Is that possible?

I actually thought I was buying a 6hp as that's what is on the cover and what the seller told me it was. It wasn't untill I checked the model number (BE5DRLSER) that I realised it was a 5hp.

 

[jbjennings]

Re: ?derated? engine, what does this mean?

I was thinking that derated referred to the way engine manufacturers change the intake manifolds, carbs., exhaust tuners, and other such things to alter the amount of horsepower produced by the powerhead. The blocks they use are rated to produce say 35hp., but with the different stuff they use they can detune it to produce say 25hp. Who else but Chinewalker would know that it was the reed plate on your 5hp! I would also not know that the D in your model number meant "derated".
Weird,
JBJ