Cummins Marine Diesel Repower Specialists › Forums › Marine Transmissions › ZF Transmission Noise in Gear at Idle Speed

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  • June 19, 2023 at 5:06 am #150268

    Kraig Kirby
    Participant
    Vessel Name: WiHoKiii

    We’ve got a 2010 Sundancer with QSB425 and ZF V-Drive transmissions, ZF 85 IV,  a noticeable noise started happening when in gear at idle and I’m looking for help with ideas of the cause.  I checked fluid levels, temps and pressures at speed and all seem to be normal and the port transmission has no noise.  The serial number on the unit is 30803-S.  I’ve got a video I’m trying to reduce file size to load, thank you in advance. Kraig  

    1 user thanked author for this post.
    Bob Schmetterer
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Viewing 6 replies - 1 through 6 (of 6 total)
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  • September 13, 2023 at 6:30 pm #154377

    Ren Hoek
    Participant
    Vessel Name: Blue Yonder
    Engines: QSC 8.3 600hp
    Location: Chesapeake Bay
    Country: USA

    I have the same chatter on my ZF 286A transmission.  When I bought the boat new 12 years ago, ZF came out and told me it was normal gear clatter.  They said as long as the noise goes away with a slight increase in RPM, don’t worry about it.  If I bump up the throttle by 10 to 20 RPM, the noise goes away.  After 1200 hours of use, the noise at idle is still there. I have never found metal in the suction filter nor had any abnormalities reported with oil samples.  It’s irritating but I don’t think it is a problem.

    September 13, 2023 at 8:36 am #154349

    sfranger239
    Participant

    Same problem with a 220a

    Even after a rebuild I am having the same noise that you are having. Any solutions. Props, shaft, coupler turned true to help rule out. 

    June 22, 2023 at 9:26 am #150512

    Kraig Kirby
    Participant
    Vessel Name: WiHoKiii

    Thank you for the reply.  The idle speed is 650rpm, the fluid is full and we’ve found when accelerating the noise gets better.  We are going to sample the oil and check the filter for any metal.

     

    June 21, 2023 at 11:44 am #150446

    Clark Leighs
    Participant

    what is the engine idle speed?       What is the Cummins spec. for the engine idle?

    Have you tried to  bump the idle speed up by 50 or 100 rpm? What happens?  Noise worse or better?

    Off to the side a bit but have you checked the gear box oil level and are you using the correct oil?

    Use a digital tach or one of the handheld laser pointer digital tachs from Ebay or Amazon for about $20 to check the actual idle revs.  

    Sometimes if the engine idle revs are to low there can be a clatter between the gears as they hit each other rather than a smoother contact.

     

    Just my guesswork.

     

    June 19, 2023 at 7:49 am #150275

    Kraig Kirby
    Participant
    Vessel Name: WiHoKiii

    Link to Video Short of the Noise

    June 19, 2023 at 7:35 am #150273

    Patrick Mangum
    Participant
    Vessel Name: Patty Wagon
    Engines: Cummins 6BTA 330
    Location: Charleston, SC
    Country: United States

    Post to YouTube

    Kraig,

    Post the video on YouTube then copy and paste the link here on the forum so others can see.  I’ve had good luck with that in the past.  

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    Kraig Kirby
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