Hydraulic Flat Tappet Question

Discussion in 'Engine Topic' started by CoastieJoe, Jun 4, 2019.

  1. CoastieJoe

    CoastieJoe Member

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    I am currently measuring for pushrod length on an old 350 that I am rebuilding. I am reusing the hydraulic flat tappet lifter that were in it from a previous rebuild and noticed that the exhaust lifter is very soft and compresses very easy when trying to measure the push rod length. just screwing down the rocker nut compresses the lifter. all the other lifters seem fine except this one. I'm thinking maybe I have to fill it up with oil ? but I've never done this to a lifter before?
     
  2. Cardinal

    Cardinal Veteran Member Lifetime Gold Member

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    Here's how I was taught: cut the top off a clean gallon milk jug. Put all the lifters standing up in the jug and put new fresh oil in there to over the top of them. Take a pushrod and push each lifter's plunger down and let it up until NO air bubbles come out of the. They are now primed.

    NOTE: make sure you use assembly lube on all the cam's journals and lobes, on each end of the pushrods, on the rocker balls, tip, and pocket where the pushrod goes into!
     
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  3. Cardinal

    Cardinal Veteran Member Lifetime Gold Member

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    I sell a product called an Adjust-A-Cover. I have one for standard small block cylinder heads (a tall valve cover and a short/standard height valve cover), and center bolt heads valve cover.

    http://nastyz28.com/threads/new-standard-height-adjust-a-covers.318463/#post-3632147

    They all come with 8 knockout plugs and directions.

    They are all $60 plus shipping and come with directions on how to adjust SBC hydraulic lifters with the engine running.

    PM me if you are interested in one.

    Standard Height SBC Adjust-A-Cover
    [​IMG]

    Centerbolt valve cover.
    [​IMG]

    Tall valve cover.
    [​IMG]
     
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  4. dave@ztech

    dave@ztech Veteran Member Lifetime Gold Member

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    I hope you kept the lifters is order, as they need to go back into the same place you removed them from, or you will be doing that job again, with a new cam and lifters
     
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  5. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    What's said above, and you can put new lifters on an old cam, but not the other way around. Why are you measuring for pushrod length? Unless you're installing something in the valve train that changes the geometry, stock pushrods will work fine. The stamped steel rockers don't require as precise setup that a roller tip rocker does.
     
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  6. Chevyforever

    Chevyforever Veteran Member

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    Is the gold valve cover painted or is it actually a gold anodized cover ?
     
  7. CoastieJoe

    CoastieJoe Member

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    thanks for all the replies guys. The lifters are still all in order and the rockers are roller rockers. I am not trying to get new ones I'm just double checking all the measurements since I took it out a few weeks ago since it was supposedly rebuilt before I bought it.
     
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  8. G72Zed

    G72Zed Veteran Member

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    I would use the stock (length) push rods unless the block has been heavily decked, and/or the heads heavily decked/rolled or used taller valves w/thick gaskets. As long as the lifter plunger location is within spec.

    A few ways to interpret what is the "best" length PR to use, ex: tip placement, scrub pattern width, oil hole timing, mid lift, or max lift @ retainer regardless of the other data points, or all data points combined.
     
  9. CoastieJoe

    CoastieJoe Member

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    So after trying to pump the lifter to fill it with oil to minimize the amount of movement when measuring I noticed all the other lifters don't move a budge. ? Are they shot or are they not suppose to move under a grown man's weight? Thanks
     

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