Twin D4 rpm sync issue

mostb

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I have recently purchased a 06 Bavaria 35 Sport with twin D4-225. When accelerating from idle to cruising speed, the rpms are very difficult to keep aligned between the two engines. If I move the two throttle levers forward to the same position, stbd engine will typically run about 400 rpm higher than port (2800/3200). If I pull back slightly on stbd lever, and push more forward on port lever, the engines "snap into sync". After this, moving the port lever only will affect the rpm of both engines.

I have performed the EVC throttle lever calibration routine. No change.
Any ideas?
 

GusC@AK

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I have recently purchased a 06 Bavaria 35 Sport with twin D4-225. When accelerating from idle to cruising speed, the rpms are very difficult to keep aligned between the two engines. If I move the two throttle levers forward to the same position, stbd engine will typically run about 400 rpm higher than port (2800/3200). If I pull back slightly on stbd lever, and push more forward on port lever, the engines "snap into sync". After this, moving the port lever only will affect the rpm of both engines.

I have performed the EVC throttle lever calibration routine. No change.
Any ideas?
I had a similar issue on my D4s. It turned out to be a tired turbo. I had the turbo rebuilt, issue fixed. Suggestion- toggle your display screen to read boost pressure, and run at equal RPMs under load. Check to see if you get equal boost. If so, it may be time to hook up a VODIA to diagnose the issue?
 

A_8

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I was going to say you probably have other issues with your engine and I think the above post is good advice.
 
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