most efficient way to run diesels

[Mr. Sandman]

Depends on the type of boat. If you have a way to monitor fuel consumption, (ie gals/hour)...create a graph of rpm vs speed and note fuel consumption at each data point. You will find the sweet spots (ie optimal mpg). Belive it or not, it will be at a different speed than you think.
FloScan makes a gauge to compute real time MPG (it uses fuel sensors and input from a GPS)

[Fishoholic]

I would never run any engine wide open for an extended amount of time, diesel or gas. Like said above flo scan is great. If I'm driving a boat stay around 2/3 to 3/4max throttle. that also depends on the sea state, but for the most I get it up on a plane then give it a little more. The difference in fuel economy is huge with just a few RPMs over cruising speed, relatively speaking.

[Raider Ronnie]

Really depends on which diesel you have.
Some are designed to run at lower RPMs (cat,mac,cummins ect..)
My Yanmar is a higher rpm diesel.
They want it run at 90% most of the time and don't like extended periods of idle (trolling)
I run my 315 @ 3000 - 3200 most of the time at cruise,. best speed + economy for me @@ 5-7 gph.
I max out @ 3900

[beamie]

Duke,

What are you really looking for? If it is what the engine likes Diesels want to run loaded. Like Ronnie said 90%. This creates the best combustion, fuel air mix, more boost air for better fuel economy. I am not talking gph, just what the engine likes. Lots of trolling on a diesel, not good in the long run.

[Raider Ronnie]

Originally Posted by beamie

Duke,

What are you really looking for? If it is what the engine likes Diesels want to run loaded. Like Ronnie said 90%. This creates the best combustion, fuel air mix, more boost air for better fuel economy. I am not talking gph, just what the engine likes. Lots of trolling on a diesel, not good in the long run.

Extended amount of time is bad on turbo more than anything.
Turbo washes are very important.
I did oil change and all fuel filters yesterday on mine and will do a turbo service later today.
I try to 3 turbo washes a season.

[striperman36]

Originally Posted by Raider Ronnie

Extended amount of time is bad on turbo more than anything.
Turbo washes are very important.
I did oil change and all fuel filters yesterday on mine and will do a turbo service later today.
I try to 3 turbo washes a season.

How does one wash a turbo?

[Raider Ronnie]

Originally Posted by striperman36

How does one wash a turbo?

Run engine to warm up to operating temp
While someone runs boat at full throttle inject Turbo wash solution.
50cc of solution injected with a syringe or spray bottle into side port of air intake over 10 second period
5-cc distilled water same procedure
....

repeate 2 more cycles solution then water

[Pete F.]

Originally Posted by striperman36

How does one wash a turbo?

With cars you have it done at the same place you get a shampoo for your engine.
I don't know it there are any Cartalk fans out there but they had a guy call in a while ago complaining about a problem that developed with his car after he had his engine shampooed, If you listen to the show you can guess how that went over

[beamie]

Originally Posted by Raider Ronnie

Extended amount of time is bad on turbo more than anything.
Turbo washes are very important.
I did oil change and all fuel filters yesterday on mine and will do a turbo service later today.
I try to 3 turbo washes a season.

Not quite sure what you mean Ronnie when you say extended amount of time is bad on the turbo...........yes, if your refering to idling time?

Turbo washes are very important.........well......

Some things to think about. Turbos are meant to pump air, a turbocharger doesn't really start to get loaded up until the engine is around 80% load. If you had a pressure gauge on your intake manifold you would see this.

Turbo washes. Some engine and turbo engineers will discourage the use of turbo washing. The reason is you have to make certain the water solution is going in at a fine mist. If it is going in as droplets it may do more damage to the compressor fan than the cleaning function. Some engine designs actually inject finely ground walnut shells for cleaning, have never seen this myself.

For those of you wondering about turbo washing this is a system where water and solution is injected into the air intake side of the turbo (compressor) and then goes onto somewhat cleaning the fins on your aftercooler. This will not take off any carbon buildup on the gas turbine side cause by light load, idling.

This also relates to having a good air filter, less stuff to get on the compressor. For the most part boats are a very clean environment, compared to contruction sites. Sometimes a big culprit is belt dust from a poorly aligned belt.