Cummins diesel 330 engines loss of rpm's

[Rick Smith]

I have a 2005 Maxum 3700 SY, twin Cummins 330’s engines. We were cruising at 2400 rpm’s all was good, I heard a huge swishing sound like high pressure released or a burst of air from an air gun. I loss power/rpm’s in the starboard engine. Then could not get it above 1500rpm’s?

All gages were normal, no smoke, no oil or gas in the bilge? I came in slow at 1100rpm’s on both engines boat felt normal but could not rev up the starboard above 1500 rpm’s? Any thoughts from anyone would be helpful

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[Rick Smith]

Thanks to all for the reply's!

Tony

i am not close to send pictures but spoke with “my guy” at the Marina looks like that’s the issue. Great web site by the way very helpful!!!

[Tony Athens]

Rick,

Post some good pictures of the engines as installed in the boat………………………………..I’m going with a lack of air/boost because a hose came off a turbo pipe……………

I want to “see” the install..

Curious–when was the last time your aftercooler was removed from the engine and serviced on the bench per my Protocol?

NO AIR = NO RPM

Tony

[William Walter]

Rpm

Any sort of limiting switch on your engines.i have a cruise one and two switch which would limit rpm to 1600 if in cruise 2 but that would be both engines.

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Rick Smith

[Rick Smith]

Thanks for the quick reply

No, I tried revving up in neutral, under no load, same issue it would not get above about 1500 rpm’s but at low rpm’s all seemed normal

[Rob Schepis]

Will it make higher rpm’s no load (neutral) ?

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Rick Smith

[Stephen Oliver]

Sounds like a turbo pipe, they go with a bang, but normally lots of smoke, have a look under the turbo around to the aftercooler for a pipe popped off or split..

Steve

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Rick Smith

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