I was doing some research about removing and installing hydraulic valve lifters. I watched some videos on Youtube and found this one quite informative. However, there are a few questions I should ask. There is a hole in the lifter body (which I have specified with the letter A) and another hole in cylinder head (Hole B).

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In the video (between 4:55 and 5:00), he installs a newly cleaned lifter but why didn't he align the two holes (A & B) together? 1 - If the hole B is the channel for supplying oil to the lifter, how can the lifter be filled with oil if it is installed in the wrong position?

2 - Why didn't he fill the lifter with oil first before installing it on the cylinder head?

3 - If a 16 valve engine has 12 good and 4 bad lifters, is it possible to replace only the 4 faulty ones and keep the good ones?


2 Answers 2


Since the first question is answered, I'll focus on the other two.

2 - The lifter is filled with oil pressure, not just some oil poured in. The manufacturer dictates how to handle the initial install of the hydraulic lifters. Here's Crane Cams and Lunati instructions as examples.

3 - Technically, yes. However whatever caused the 4 to go bad could cause the others to go bad shortly. Since getting to the lifters isn't a 10 minute job, it's best to replace all of them.

  • Thanks for your answer. I know the lifter is filled with the pressure generated by the oil pump but if it is installed empty, it may run dry for a few seconds or minutes which can cause damage. Since, most vital parts (like bearings and piston rings) are installed with some initial lubrication, I thought it is better to do the same for the lifters too.
    – LFY MP7.3
    Nov 3, 2021 at 17:24
  • 1
    Lubricate it like you would anything else in the engine, and those few seconds shouldn't damage it. Nov 3, 2021 at 18:32

Because the cam operates slightly off-centre on the lifter so it rotates in normal circumstances. The machined groove allows the oil to travel to the hole in the lifter body from the hole B you labelled.

When lifters get sufficiently dirty to stop rotating although they still travel vertically the cam can wear a groove in the face of the lifter.

If you inspect the lifters on the engine you are working on, then you might see some marks left by the cam during operation.

  • Could you please edit your answer and answer my 2nd and 3rd questions?
    – LFY MP7.3
    Nov 2, 2021 at 8:33

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