Looking for ideas for a friend...

[avimgod]

Friend is looking at a 21 foot dual console..not sure of the hull design, but it is equipped with a Suzuki DF140 (2007, unknown hours) with a standard 14x21 aluminum prop (rough shape)..

During his test float yesterday, the motor wouldn't rev over 3200 RPM, yielding him a top speed of 28MPH...

I have told him to have a marina check out the fuel filter, plugs, oil, injectors, and lower unit oil condition...

am I missing something, from what I can gather the DF140 is a good motor, and it has what appears to be the origional prop on it, he SHOULD be seeing 6K and 40MPH or so...

please advise.. here EDIT

 

[99yam40]

Re: Looking for ideas for a friend...

compression or leak down on all cylinders is another one to look at, but it sounds like it is sick if 3200 is all it will do. Lean running will eat pistons if that is its problem

 

[mutch]

Re: Looking for ideas for a friend...

Was there any warning lights at 3200 sounds like it may be in fail safe mode and will not rev out .

Also possible the neutral switch is jammed telling ecu that drive is in neutral so will not rev out.

 

[JB]

Re: Looking for ideas for a friend...

Very likely that a bashed up prop with too much pitch on a big boat is the only thing wrong with it.

The DF140 is small displacement for a 140 and doesn't really get on the cam until it is over 4K. That is a lot of boat to be pushing with that engine with the ideal prop and 21" sounds much too steep.

 

[mutch]

Re: Looking for ideas for a friend...

yes that is a large prop may be 17 or 19 not 21