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Adjusting lifters--Roller lifter collapse?

Discussion in 'COMP Cams Support Forum' started by daddytoy, Apr 18, 2018.

  1. daddytoy

    daddytoy Member

    Joined:
    Dec 10, 2011
    Working on my SBC 383 that's been running the last four years with a Xtreme XFI 268 Comp Cam and their roller retrofit lifters that came in the K kit (like 853-16) plus an XFI EFI system. I pulled the engine out in December for a refresh (clean, paint, gaskets) and put it back in the car this weekend. When I tried to start it, it pops through the throttle body and in the exhaust and won't start. I disabled the ignition and injectors and I could hear one or more cylinders pushing air back into the intake when cranking; like a valve was hung open. So, I'm trying to run the valve adjustment again. Since these are hydraulic rollers, it should be simple to run the poly lock nut down to zero lash and then put 1/2 addition turn on it. However, when I put that 1/2 turn on it, I can see the roller rocker opening the valve and not preloading the lifter. This is happening on 14 out of 16 lifters. I pre-lubed the engine before assembly back in January and then did it again when the engine was installed this weekend. Assuming that these 14 lifters are collapsed, I spun the engine with the starter for 15-second bursts 10 times, noting 60 psi oil pressure and oil flowing out of the bleed holes in the rockers. When I try to pre-load the lifters, the valves are still opening on 14 out of 16 lifters.

    At this point, the intake is still on as I would really like to avoid having to remove that to get at the lifters.

    Any suggestions? If the intake has to come off, how do I test the lifters for collapse? Is there a better way to get them pumped up (the usual bath in a coffee can full of oil overnight?)?

    TIA for any suggestions.
     
  2. daddytoy

    daddytoy Member

    Joined:
    Dec 10, 2011
    Thanks, AA. I ended up removing the upper retaining rings and then using a combination of compressed air and stroking the piston to push out the oil that had the piston locked up. It didn't seem to be congealed, but it obviously was thick enough to prevent bleed down. With the pistons freed, I set preload per the usual procedure and the engine is running now. Fingers crossed that they don't pump up again.
     

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