Adjusting valve lash 5.9QSB 230 HP

[Jim Serrill]

I plan to adjust the valve lash on my 2012 5.9 QSB with 700 hours. I can hear valve clicking and it “throbs” at idle. Questions. Is the a TDC marking on the engine, and does a Cummins barring tool work to turn the motor over?
Thanks
Jim

Topic

[Scott Lambert]

While we are on the subject of QSB valve adjustment, my QSB 5.9 380hp is 11 years old with 1100 hours. As far as I am aware the valve lash has not been adjusted. When you say typical 5000 hrs between adjustments would that apply regardless of age? Or is it something that should be done every 10 years or so? QSOL says every 5000 hrs or 4 years but I have not heard of anyone doing it every 4 years.

[Tony Athens]

QSB 5.9 Valve adjustment

I would not suspect you have a valve lash issue as I have never run into one with this engine ( typical is 5000 hours between adjustments).. I would more suspect the fuel actuator on the CR pump is acting up.

This is not an easy engine to bar over” as where that tool fits is behind the aftercooler –To use it, you really need to remove the aftercooler for access. Maybe it’s time to properly service it anyway ( 6+ yrs in seawater??)

No TDC mark that I am aware of. Have you checked QSOL as to a “how too”.. Some of the stuff they publish is pretty good that way. I personally have not researched that yet.

Tony

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