Cummins pulled for a Scania

Duramax0530

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Yes, there should be more to it than just idle showing load. Did it turn up to rated RPM and what was the boost then? That shows if it's making power or not. Like I wrote further back a good running 660 M11 doesn't make a boat that much faster than a 450C. As for warranty response it depends on who is covering it and how much the engine is at fault. I've had situations where we were slow to respond and other times where I've repaired or replaced the engine at a dealers before the boat was even advertised.
Couldn’t get to max rpm even with a way undersized wheel.
 

Powderpro

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Couldn’t get to max rpm even with a way undersized wheel.
Give me the specs on the boat like length, width, weight, engine hp and wot rpm, trans reduction, and current prop size. I can get you real close on what the prop should be. Free of charge. I need accurate info, no guessing or it won’t work.
 

Duramax0530

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Give me the specs on the boat like length, width, weight, engine hp and wot rpm, trans reduction, and current prop size. I can get you real close on what the prop should be. Free of charge. I need accurate info, no guessing or it won’t work.
Will message you
 
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Sounds more like a fuel supply problem to me. Like a restriction in the hose, pick up tube, or filters.
Jerry, you are looking in the right direction. Often when i did a warranty installation review or a claim it was important to look at everything when the engine wasn't a direct replacement and didn't perform like it should.. Especially going from gas to diesel i would see the installation holding back the new engine. Going from one size anything to a bigger engine it could be fuel or exhaust size. That's why top end numbers would be important, not idle load. I've run them out of 5 gallon buckets of clean diesel while monitoring exhaust restriction and boost to see if it was the engine or the boat. For all it's size the M11 isn't that much stronger than the 450C. I think it's 1300 ftlbs over the C's 1100. As for upping to a 13liter from a C 8.3, I couldn't even estimate the cost of increasing the size of the shafting, prop, stuffing box, intake water and air plumbing, exhaust, mounts, etc.
 

plowin

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What size fuel lines are feeding the motor? Shocking how big they are required to be to feed these new motors regardless of what they actually burn for fuel.
 

Tenacity Tuning

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Another thought on this. With the hi load at idle, I also am thinking fueling issue. But it could be a bad set of injectors or a high pressure fuel leak on the return side, etc. Load is measured by RPM and an extrapolated number derived from the Fuel Control Actuator on the High Pressure pump. That metering valve really controls the fuel flow to the engine as well as rail pressure, etc. If there were a leak or hi return rates on the injectors the pump will be pushing more fuel for the same rpm/real load. That will in turn cause the derived load to read higher than what's actually going on.
On another note, there's a reason why you see a bunch of the 30,000lb wesmacs and stuff with C18's or other engines of similar size.
 
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Couldn’t get to max rpm even with a way undersized wheel.
Who supplied that prop? How do we know it's undersized? Was it the one from the original engine? If it was then the boat won't increase in speed, the engine will just top out underloaded. Boost shows load.
As for Tenacity Tuning, yup, if you want to run 15+ tons fast, you need a liter a ton or more to get you what you want.
 
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Powderpro

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Who supplied that prop? How do we know it's undersized? Was it the one from the original engine? If it was then the boat won't increase in speed, the engine will just top out underloaded. Boost shows load.
As for Tenacity Tuning, yup, if you want to run 15+ tons fast, you need a liter a ton or more to get you what you want.
Mike, I private messaged him. From the info I got the engine isn’t able to turn the prop that it should be able to turn. I ran the prop numbers of the new engine versus the old engine, for whatever reason the new engine isn’t putting out the power it should. Seems like a Cummins mechanic could get to the root cause of the lack of power.
 
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Quick side note. My son got his 100 ton license and wanted to look at some boats. Down here on the Chesapeake they aren't built like they are up north but in glass they hold up ok. Up pier after pier looking at shit he could afford. At one yard we passed a 40 something foot, glass, well built, oyster dredge rigged deadrise. The dry stack was so big he had a Home Depot bucket over it. Guy in the next slip said he knew him, I could look, I'm not big on trespassing but i couldn't help myself. Lifted the engine box, C18 Cat, SWAC. What you burn in fuel you save on ice, you get back to the dock so quick.
 
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Mike, I private messaged him. From the info I got the engine isn’t able to turn the prop that it should be able to turn. I ran the prop numbers of the new engine versus the old engine, for whatever reason the new engine isn’t putting out the power it should. Seems like a Cummins mechanic could get to the root cause of the lack of power.
Ok, interested to know what's up.
 
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