Im still not sure why the soak or not soak is being pondered. New lifters must be soaked to fill the lifter bodies up… so that there is a cushion of oil internal to the lifter. Yes @Nevada_545 is also correct in that actuating the lifters while submerged helps speed along the process of filling the lifter body…no question about that.
There is a reason they are called “hydraulic” lifters as opposed to solid lifters…its because of that hydraulic action that oil in the lifter body provides
They need that oil to be inside the lifter… and when the lifter goes bad (or its check valve) they cannot “pump up” … it is unable to retain that cushion of oil and collapses because it cannot “hydraulic”.
This is a very basic tenant and rule to lifter installation 101. Its not up for debate.
Here is what Comp Cams says in the installation instructions for their hydraulic lifters:
It is not necessary to “pre-pump” hydraulic lifters full of engine oil prior to installation and valve adjustment. It is actually undesirable to do so as the “pumped up” lifters will cause the valves to open during the adjustment process, rather than positioning the lifter plunger in its operating position as it is supposed to do. “Pre-soaking” hydraulic lifters in a bath of engine oil is a good idea but not mandatory. Doing so ensures that the lifters are adequately lubricated on their outer surfaces prior to installation.
I also looked up instructions from Crower and Lunati. Both say to coat the cam lobes and lifters with lube. Lunati specifically says to use a quality (NON synthetic) motor oil. Neither says anything about soaking or “pre-pumping”.
Crane Cams says: Many people mistakenly believe that hydraulic lifters must be soaked in oil overnight and be hand pumped up with a pushrod before installing into a new engine, however this is not necessary. In fact, this could cause the lifter to act as a “solid” and prevent obtaining proper preload.
On the other hand, Rhoads wants their lifters to be completely filled with oil, using the soak and pump method.
I’d say, whatever brand lifters are used, follow that brand’s instructions.
Note that it would be good to prime the engine’s entire oil system after the lifter preload has been adjusted, and before starting up a new engine (or one that has been setting a long time) for the first time.
Well since this thread is going to go on and on with various opinions and anecdotes, I’ll throw in my $0.02.
The only lifter I ever replace along with the one rocker arm and bent push rod ( curtesy of high school friends cross wiring my engine) was on a 361 Plymouth. Rocker all on a single shaft, no adjustments, dropped in the lifter, then push rod, reinstalled the rockers. Fired it up, ran perfect.
There have been instances where VW hydraulic liftes which were not pre-soaked actually jumped and damaged the lifter and/or the cam lobe. The German service instructors were pretty adamant about soaking them and the Germans are thorough if nothing else.
I had to sit in a class once listening to 3.5 hours straight of how an automotive battery functions…Mind numbing at times.
Not once in my life nor have I ever heard of someone replacing a full set of lifters on an old engine. One maybe and even that can be debateable. The problem with flat tappet lifters is that the valve lifter surfaces are actually ground at an angle.where the surface is convex. The convex wears off and along with it the cam lobe which is not square ground. There is (or was before wear) a taper on the lobe from one side to the other. When that happens the lifter and valve no longer rotate.as they should.
I have a tapping sound in my engine that only happens when warm I’ve replaced the lifter I thought was bad but still not fixed so ima just replace all it’s the only thing I can think of flex plate ain’t cracked rod bearings are good & to me it sounds like lifter tap here a link to the car running if you’d like to hear yourself https://youtu.be/qhS3xyLGH7I
I’ve just recently participated in the “$100 car project” a friend of mine was running to help a family in need in his neighborhood.
We’ve got 15-years old Civic after the elderly prior owner lurched with it under the bus bumper, squashing the hood, headlight and radiator.
Per prior owner, the car had “tapping sound” at idle, and once we pulled the bodywork in place and restarted the engine, it was indeed a tapping sound, so we were prepared to the worst and knew that local junk-yard had moderately worn engine for reasonable money.
Once we pulled the bodywork in place, I left, my friend kept working on it in his garage, then he called me and said he fixed the tapping sound for free
It was some loose part externally on the engine block, and I swear it was sounding pretty much like a rod knock to me, but alas, engine purrs like a kitten again, the total expense was under $500 to replace the hood, radiator and one headlight.
