View Full Version : Priming hydraulic lifters
10-15-2005, 07:55 PM
I bought new hydraulic lifters for my 263 L8 (52 Super). I didn't know they should be primed before installation. My mechanic got the engine running and was adjusting the valves and said that three lifters were collapsing. Upon removing the lifters, we found we could NOT compress the plunger in any of them using a pushrod - they were acting almost like solid lifters. One of them would compress slightly and another would collapse in, but would not pop back. The originals compress/decompress just fine.
Did I really screw up by not priming? Aren't hydraulic lifters supposed to compress/decompress even without priming? I'm thinking these lifters were machined poorly. Any thoughts are appreciated.
10-17-2005, 11:51 AM
When new, they -usually- can be compressed & relieved. When primed, it´s IMPOSSIBLE to compress any of them even a millessime of inch.
From prehistory (early forties) to last year, lifters ALWAYS primed for themselves just dropping them in da hole, timing accurately the pushrods and starting the mill: circulating oil primed the lifters and the horrorous noise from down there goes gradually loosening clicketies to the sweet rumour it has to be.
I'd say last year because my last lifters set did HAVE to be primed very very carefully. Sure da hell you have up there in the USA lots of Buick lovers aimed to explain you how to it. My English is mmm... cathastrophic.
Finally, I repeat: When primed, they have ZERO tolerance to compression effort. If they allow a mere 1/1000" plunging under hand-and-rod action, you'll have great heat & performance troubles in all the engine.
10-17-2005, 03:20 PM
If your engine has been setting for some time lifters should be primed before installing. This for two reasons. If after priming you can still compress the unit it is no good. Use another one. Also if you prime them you will be saving wear and tear waiting for the oil pressure to build. The lifters may bleed down during the run up. The lifters are quite simple. If you have an extra take it apart. They need clean oil and if memory serves me, yours get their oil thru the push rods, it means the rocker arm assembly has to be in good shape to maintain a good supply down to the lifters. It should be visible with the valve cover off and engine running. You mentioned some lifters would compress and de compress. Others would not. A lifter that is primed should hold pressure, if you can compress it it is no good, perhaps a bad check ball or seat. Do not use it. If it is not primed,empty you should be able to compress it and it will come back by return spring tension. From your interest I suggest you disassemble an old one and see what makes it tick. Ride safe.
10-17-2005, 06:21 PM
It would seem that my new lifters are non-compressible following installation and initial run of the engine. I did not try them before installation. This sounds like a GOOD thing. One will compress, but sticks - sounds like a bad one.
Just wondering... how do you prime a lifter? Immerse in oil? It looks like the oil will not easily flow through that little hole in the top!
10-18-2005, 05:33 AM
If all is well now, engine running and quiet all is well.. In the bleeding process when you compress the lifter you evacuate the air thru the bleed hole de compression will then suck the oil trrough the same hole. Both actions naturally require the bleed hole to be clear. In operation they act like a cushion.
10-18-2005, 11:01 AM
Sorry, but you don't GET oil for lifters thru pushrods, but contrary: Oil shoot from da pump go to work on hidraulic lifters, feeding'em and following his way thru pushrods hole to valve train (rockers, valves & all), then overflows and fall to the engine bottom.
At my own risk, I bleeded my lifters (all of them for be sure) this way:
Place the little damn thing firmly, vertical, on the bench. Take off the safety device (usually some snap ring) c-a-r-e-f-u-l-l-y. It tends to jump flying to Alaska if unaware. Put it apart. Take the first fine plate. Apart. Take out the tiny piston with some fine hook and put it apart. If there's another safe plate, or blanking plate or anything about, off with it also. EVERY COMPONENT HAS TO BE ULTRA-CLEANED AND PLACED CLEAN-CLEAN-CLEANEST WAY.
Then, block with a finger the bottom hole and pour clean oil to top of cylinder. Take, if it were there, pieces under piston and piston, and begin inserting it into cylinder, relieving your blocking finger just to let drip the extra oil. Just -ĄJust!- the piston leaves room to place the snap ring, insert it. Then you can be SURE thislifter is fed.
10-18-2005, 03:37 PM
I have bled many lifters in the way I described, in 52 I was employed as a mechanic in a Buick dealership. (I'm old) I understood this car was a straight eight engine. The oil feed in a V 8 is entirely different as is the design of the lifter itself. The straight eight was a favorite of mine for years, but the interstate highways with the higher speeds brought an end to its usefulness. If my info was not correct for your engine, pleasde excuse. Either design are still quite simple. Ride safe.
10-19-2005, 06:05 AM
Everyone had to hat off facing an old US mechanic for Buicks.
My compliments, respectfully!
And about the desperately poor performance from my Special Sedanette 1949, I had to learn six years ago to fight the modern tendences: Here in Spain NOBODY goes highway under 100 mph. Except big trucks. (Small ones goes usually 80/90 mph).
Somebody in this forum wrote something abouth switching rear ends. He told that a 1953 in my 1949 beauty coulda improve lotsa things. Well, from that date onwards I've got dreams, nightmares and needed some neurologic help in order to keep myself sane. Hey, guys!! I'm in the old and sunny Spain, and here those pieces are more legendary (expensive) than a picture from Picasso.
10-22-2005, 06:17 AM
Thank you for your input! My engine is, indeed, a L-8. I took a long hard look at the 52 Buick shop manual. It spells out a procedure for testing hydraulic lifter leak-down which involves immersing the lifter in a tub of transmission fluid (20 oz) and the rest kerosene and pumping the lifter to remove air and to fill the lifter with the fluid. Lowvoltage, I think you've identified the situation. Thanks to both of you for your responses!