I had pumped up the lifters with an oil can as I have done in the past, slipped the lifters in from the cam chest and held in place with magnets. After buttoning up the cam chest my 17' 107, I removed the magnets but never got around to doing the pushrods.

Around 8pm, I was getting hungry and ran out to get some Chinese food. After eating I fell asleep on the couch and didn't wake up until midnight. Sound familiar?

My question is will the lifters bleed down without pressure from the pushrods and will I have to take them out to pump them back up with oil?

 

They will not bleed down any significant amount since there is no pressure on them.

And even if they did that is not really a problem. The internal spring will keep them extended while doing push rod adjustment, and they will pump up quickly when the engine is started.

 

Lifters were never pumped up to begin with, and all you do by squirting oil in to the side of the piston, is just push the upper air out of the lifter, not the lower air out that is still below the piston.

So until you run the motor (ranked by not allow to start until the oil pressure comes up for a few second/few engine systems, so you have a consent sourced of oil pressure into the lifter, the piston is being pushed down/allowed to come back up via spring pressure multi times, your not going to get the all the air out from below the piston body.

If concept it to pull the piston out of the lifter body, fill the lower body of the lifter with oil with top straight up, then good luck on trying to get the lifter C clip back in place at the end, since will need something like a press, and will be there for a while as well. The piston vavle allows oil to enter from the top, but not exit that way, and what keeps the lifter pumped up, is the slow release of oil from around OD of pistons to lifter body.

So oil in the side of the lifter to pre-lube it, is just that, and will make sure that there is extra lube on the piston parts, so as they are run, piston does not seize in the body, and can self purge the air out of them as they are being run. Also point out, when you shut the motor off will valve under compression, oil will leak out from about the piston to body, and will take a second or two for the oil pressure to come back up on the motor, and allow the lifter to pump back up.

So don't confuse of adding extra oil to the upper body parts via the side port, but it not removing the lower air from the below the piston, much less pumping them up.
To do that, would need to submerge the lifter in an oil bath, while at the same time pressing the inside stack of lifter down/allow it to spring back up multitude of times, to work the lower air out before the piston and the upper stack as well, before the lifter is void an any trapped air. Also to point out, you have lifters that the below the pistons void is solid oil from them being use, using solid push rods, then need to pace tightens down the rockers with solid push rods in place, since try to go too fast, will end up with the solid push rods being bent.

Simply, adding oil to side of body port is not a bad idea to add a little extra oil to them, over the thinner assembly oil use to assembly them in the first place, but once you have the motor back togetther, pull the plugs and use the starter to spin the motor a few times until is comes up to pressure to begin with, and then a extra crank of two on the starter, to allow the lifters to work out all the air still left in them and push motor oil up the rocker assemblies, before you go to start the motor in the end.

 

Nope...

 

Exactly.
No need to take apart to oil again. They will be fine to set the pushrods. When you DO start the bike for the first time, the lifters WILL chatter for abit until completly pressurized. It'll be fine.

 

Sorry for piggy-backing off this thread.

I recently had lifters installed by a friend and the bike now chatters for a little bit when starting cold or after the bike has sat for maybe 30+ minutes. I had a separate friend who is also a mechanic check the push rods and make some adjustments. It did not make a difference. Should I consider having someone check and see that the lifters are primed?

I just want to make sure in the long run this isn't going to hurt anything. After a couple minutes my valve train is whisper quiet.

Thank you!

 

As soon as the oiling system sees oil pressure, hydraulic lifters see it also and are at there operating position. There is no issue with them bleeding down a little when the engine is shut off.

 

What lifters, since did a write up on the old Evo A lifters, where piston sealing edges for the seal plate had a great deal of burs left on them, that was causing problems with the motor being able to keep them pumped up.

Hence oils should be able to go to the piston through the bottom check valve, but should not be able to come back up that way, only around the OD of the pistons body, and them up around the Id of the bodies.But yes, if motor is not running, and lifter is under compression by holding a vavle open, lifter is going to bleed down, but one pump starts pushing pressure, should pump back up within a few strokes.

So look at the sealing ring surface of the piston to check plate here that has burs, and the how it wearing the sealing plate as well,


Verse the clean up of the burs on the rings, so it will not trash the sealing plate that its other side is still clean to use,and so the plate can seal correctly to prevent oil back blow by.


Simply, call me paranoid, but when replacing lifters, like to pull the new ones apart, to give them a good once over/detail clean up burs that the manufacture may have left behind.