I have 30 miles on a fresh rebuild, and I have one lifter that won't shup up. It didn't make noise until I started driving it after the break in process. I pulled the rocker shaft on that side and realized I can't pull any of the lifters with the new edelbrock intake. The gap between the intake and head is too small! What should I do, keep driving it and see if it clears up, or pull the intake off and replace lifters. (which I don't want to do). And the lifter does NOT make noise at idle, just as soon as i hit the gas.
You have the most oil pressure and flow that you will ever have. The check valve in the lifter may not be functional. The hole that a allows oil in to pressurize the bottom of the inner piston is, from memory, about the diameter of a toothpick. It can flow enough to keep the piston tight against the bottom end of the pushrod at low speed, but not at higher speed, as the check valve is not keeping the oil captured under the piston.
Most times, you would have a tap at idle, but your engine is so new that you likely have real good pressure and the system can keep the piston 'fed' enough to be quiet.
You *might* be able to break it loose if it is jammed by taking it for a high speed run. If it is a defective (or missing) check valve, a run will not make it work. Are you sure you can't fish it out through one of the openings near the center of the head?
I'm sure I can't fish it out. I even lifter it out of the bore and it stopped at the intake. I held it between 2000 and 2500 for about 20 min. using rotella and this zinc additive that my machinist gave me. ran it for a day and then changed the oil.
Do you think something like marvels mystery oil might clean it out or is that bad for new engine?
and as long as romping on it a few times won't hurt anything, I could try that too. It's just that it is a LOUD tap. It makes me cringe to drive it.
I guess it could be a header gasket, but I fixed a header leak and it sounds different. do header leaks make noise even when decelerating? cause this makes noise all the time except when it is at idle. but I guess considering how load it is it could be a header leak
Assuming you know which lifter is goosey, remove the rocker arm cover. Place some cardboard at the lower rocker cover gasket to minimize oil dripping on the exhaust manifold. You can direct the majority to the rearmost drain...
Start the engine. At idle, you should be able to press with a piece of wood on the heel or pushrod end of the rocker arm, and make each and every lifter tap, release, and it should quiet down by steps, getting quieter and quieter as the inner cylinder gets filled with oil. That is the one check I can think of that you can do without removal. What it tells you is that you have good oil flow through the lifter and the check valve works. It would take several cycles to collapse the lifter, as the check valve will stop you on each 'lift' cycle, but you persevere and force the oil out.
What is happening is that your hammer handle (what I use) is pretending to be a valve that is spring loaded and wants to ride further 'down' in the lifter travel. The hydraulic lifter is supposed to handle this by allowing extra oil out when the lifter is 'unloaded', as the spring is stronger than the oil pressure. When the cam starts to open the valve, the oil inside the lifter is trapped by the piston moving relative to the lifter, a little bit, and closing off the supply from the lifter gallery. The lifter body follows the cam lobe, moves up, and the piston stays in one spot until the cam closes the valve and unloads the pressure on the piston. The oil pressure can now get behind the piston and re-fill, if necessary, the lifter. The valve will not open completely if the check valve is not working, but it could possibly be quiet at idle with a good supply of oil.
the machinist only built the short block.
it now taps at idle.
I thought it sounded to loud to be a lifter so I replaced the header gasket, but it still taps.
I will go put the piece of cardboard below the rocker shaft assembly, and see if I can pin point the problem lifter.
Is it bad to add something like marvel mystery oil to a new engine?
And no I did not prime the lifters before install. the machinist went through a process with me to figure out what size pushrods to use, and it required me to bring each cylinder to tdc with the pushrods and rockershafts installed, but the intake off so you can see if the pushrod is about halfway through the travel of the empty lifter. You can push down on the back of the rocker and watch the plunger continue to go down. if it's bottomed out, go shorter. if there is slop, go longer. they were bottomed out so I got a shorter set and they were perfect. All lifters are quiet except the one evil lifter.
I will go try the cardboard trick and see whats what.
o.k so as soon as I unhook the #3 cylinder spark plug wire, the noise stops. this sounds bad. that can't be related to a lifter could it?
I pushed down on the #3 rockers with a piece of wood and I WAS able to get them to tick and then stop. so I don't think it's a lifter. PLEASE HELP
It is really hard to tell. It sounds like it's coming from a rocker on that same #3 cylinder. I noticed that same rocker is not getting as much oil and the push rod is not spinning. could that be it?
and that I crawl under it to double check the header gaskets and it sounds very loud under the header too. It's just surprising how loud (and embarrasing) it is. I just drove it home for the weekend and won't be driving it again until monday (or until it gets figured out.) on the drive home, it tapped the whole way. it never stopped except for once while sitting at a light idling.