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  1. Fingers

    Piston rings not seating

    From the pics, it looks like the cylinder finish is too fine. But that is just a guess. To verify the blow-by, use your compression tester kit to pressurize the cylinder with air and listen for blow-by with the piston at TDC and the valves closed. You only need 10-15 PSI. Keep in mind that the...
  2. Fingers

    Piston rings not seating

    Wrong, the top of the head and the crankcase are connected partner. Both pressurize together.
  3. Fingers

    Piston rings not seating

    I'm not ruling out blow-by, but I am thinking there is a bad seal in the turbo or maybe a valve seal. The smoke will NOT increase appreciably from blow-by if you put your finger over the vent.
  4. Fingers

    Mike L has passed away.......

    Wow. The diesel world just lost one of it brightest stars, and some of us a great mentor and friend. Till we meet again.....
  5. Fingers

    Twins with Twins, Anyone?

    Glad the pistons made the short list! Now clean out that intake before you screw up the tops of those pistons with shrapnel!!
  6. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    They don't answer my calls.
  7. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    They are essentially the same. There is a little variation from piston to piston, but it is very small and has no impact in this case.
  8. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    In this last picture, you can see how much the oil gallery is tilted. I am going to call the shift the root cause. Right now, I don't know how to detect this going forward.
  9. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    It is the only one through the crown that I recall. There have been a few that have cracked below. Right above the pin or on the skirt. Essentially all of those were discovered when the engine was torn down for other issues. Otherwise, the owner was totally unaware of any issues. For this...
  10. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    Spray pattern is typical. Nothing unusual.
  11. Fingers

    New place to burn a hole ina piston. No crack, just hole.

    They are "thinner" there, but there is very little stress in that area. NOT an injector issue. At least not directly. Noticed some metal transfer to the pin, where there is none on others. Might be from failure or an indication of the cause like lack of oil cooling. There is a crack in the...
  12. Fingers

    New place to burn a hole ina piston. No crack, just hole.

  13. Fingers

    How did you get into your career?

    I needed a job. Westinghouse was hiring and I am a painfully quick study.
  14. Fingers

    How did you get into your career?

    Hell, I'm going to be 61 this year and still haven't settled on a career. I've been paid to be: Body Mechanic. Dish washer Computer Operator Operations manager Software Engineer. Carpenter Mason Heavy Equipment operator General contractor machinist Welder nuclear refueler Specialty crane tech...
  15. Fingers

    LLY - Cracked piston

    Glad it worked out for you!! I had the same thing happening at one time. I welded eyelets on the turbo and the hot pipe and put an adjustable link between them to hold that sucker together. Been that way for 15-16 years.
  16. Fingers

    LLY - Cracked piston

    I can tell you for a fact that they do rock while running. Especially when cold. Keep in mind that the GM (and other manufacturer's ) specs take into account piston rock within the PTW service specs.
  17. Fingers

    LLY - Cracked piston

    Why do we Measure Piston Protrusion? - So the piston does not hit the heads. Given that, you want to measure the piston where and when it sticks out the furthest and base your gasket selection on that number. Why do we keep the clearance tight? - performance reasons. The tighter the clearance...
  18. Fingers

    LLY - Cracked piston

    By Spec, you measure across the pin. In real life, you measure the top and bottom and rock the piston to see the max protrusion. Not a big issue with cast since they don't rock much if the bore is in spec, but a big deal when dealing with Forged and the larger piston to wall clearances.
  19. Fingers

    Twins with Twins, Anyone?

    Would still be running Crank RPMs. If Shaft speed is the issue, you have solved nothing. A 65 tooth gear would be perfect IMO.
  20. Fingers

    Twins with Twins, Anyone?

    IMO, you are over spinning the pump. The simplest solution would be to under-drive a single belt driven 12mm pump. Keeping the max pump shaft speed around 3000 RPM. The "Cool" solution would be to change up the gearing on the valley pump and under-drive it.
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