QSC 540 derating

[Luke Nelson]

Hi All ,

Is it possible to derate a QSC 540 down to around 400hp on the ECU? I think I am asking something that is impossible but I can ask.

 

I understand the engine sees the prop but the class surveyor sees the the plate on the engine  and works from that even if its a bit backwards.

 

Topic

[Luke Nelson]

Thanks for the input Tony, I agree with the engine sees the prop principle but the surveyor and the local authority says the shaft sees the engine HP not what is has to turn.

 

Rob I am in the process of a insurance claim and looking to find  replacement engine options with the least amount of major refit if insurance leaves me holding the bag .

 

In a ideal world I will re shaft and prop to around 500hp but it depends on what the numbers say.

 

 

[Rob Schepis]

Insurance ?

Luke, I read through your posts a couple times and I’m confused – Are you in the process of obtaining insurance on the vessel or are you repairing the vessel via funds from an insurance claim?

[Tony Athens]

1) Derate–Just assume NO

2) The QSC540 in no longer current unless you are looking at a used engine–That earlier version can be “factory rated “to  484 BHP at 2500 RPM

3) But really,  none of this matters in the practical sense as your current props/gears will determine the max HP these engines will develop, not the “name tag rating”.  If your current prop were adjusted to about 375 HP at 2800 RPM, then the QSC will see the same absorbed HP up to their governor set point with is just under 2700RPM.

 

Tony

[Luke Nelson]

Thanks Tony,

As my vessel is going through insurance  is it possible to derate a qsc 540 enough to use the same props and shafts as I have been with a 3208TA 375 propped 100rpm heavy. And keep the same 2600rpm max rpm.  Insurance does not look to be on my side at this stage. In reality an increase of shaft size and a new prop my is the solution but it may not be in the insurance budget  the way ts looking.

 

 

[Tony Athens]

Anything is possible but not in the normal sense by asking your Cummins distributor……………What exactly are you trying to figure out or accomplish?

What is a “class surveyor” and what is he tying to figure out?

Tony

 

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