So I think I have a stuck lifter in the Regal. I did some research on Hydraulic lifters, and everything seems to make sense so far. I have a tapping noise in the engine that'* been there for the last 20k some miles. I don't exactly remember when it got there; I just remember hearing it. Its not really audible at idle, but the moment you rev even slightly, you can hear the ticking. Since I've replaced the valves, the lifters are the last bits that could be at fault here.



How would I go about fixing this problem? I just dumped a can of seafoam into my crankcase (with 1500 miles on the oil) in hopes that this might alleviate the problem. Does anyone have any other suggestions? The engine also recommends 10W30, but I'm using 5W30. Should I try using a heavier grade oil? Or is my only option to replace all of the lifters? Is there a way to figure out which one is bad or stuck? These things are about $10 each, so I'd prefer not to have to replace all 12 of them.



Any help would be appreciated.

See if the seafoam loosens it up, then go from there. What engine is this on? I have a set of lifters from a series2 that I can ship you cheep.

Series 1, 95 L27.

I did some more reading, and apparently there are a few things you can use to free stuck lifters. RISLONE ENGINE TREATMENT is one of those. Apparently you drain a quart of oil and put that in there. Alternately, I've heard of people draining a quart of oil and putting in a quart of transmission fluid. Anyone have any experience with either of these? I've also heard of people running thinner 0w-30 oils in conjunction to some of these. I just replaced my heads and put in new gaskets from the heads up, so I'd prefer to not have to take the LIM off again, which includes valve covers, rockers, and draining the coolant. I'm tired of being under that hood.

If you just had the heads off. You should pull the valve covers and check all your rocker bolts. We frequently associate valvetrain noise with lifters, but it'* really slop anywhere in the cam to lifter to pushrod to rocker to valve area that can make noise.

Look at the bright side.. you know all the stuff is going to move easily. (Yeah, Gunner didn't exactly give me a big smile when I said that either..lol)

Being new valve cover gaskets you can remove them and reuse them.

Oh those rocker bolts are tight, believe me. I swapped my 1.8 ratio roller rockers from the old heads to the new ones, so I know for a fact they're tight. I just changed my oil with 3 quarts synthetic blend 10w-30, and 1 quart Rislone Engine Treatment. Its a lot smoother running so far, so we'll se if that lifter noise goes away. If it doesn't go away in 3000 miles, I'm buying new lifters.

Well, I have some good news, so far. The vibration has lessened a bit, and now I can no longer hear any lifter tapping up to 2000 rpm, and I can't hear much past that because of the exhaust noise. The powerband also seems to feel more even, and the engine is overall quieter. Interesting considering that Rislone engine treatment is designed to clean out everything. I'm hoping the lifters were just clogged and not actually worn. I'll try to rev it from under the hood later since I can only rev so loud in my work'* parking lot without looking like a tool.

If you can't hear it from driver seat with hood closed it should be fine.

Good to hear.

So I spoke too soon. The vibration is just as bad as before. I guess I just didn't feel it when I posted because I didn't let the engine warm up completely. The noise is also there; its just not as loud up to 2000 rpm as it used to be, which is partially due to the engine treatment coating all of the parts and making them quieter.

I'm going to wait 3000 miles and then replace the lifters with new ones.

A guy on the w-body forum mentioned that it could also be a problem with the cam lobes going flat and not providing the same amount of lift. I told him I didn't think it was possible, but I figured I'd bounce the idea off of you guys.

The reason I thought it was highly unlikely is because the L27 has hydraulic roller cams. Unlike flat tappet cams where the cam lobes rub against the surface of a flat tappet, the hydraulic roller cams don't have any such friction, but function more similarly to ball bearings.

Has anyone here ever heard of a 3800 cam getting flatter on any number of lobes?