hey guys,
2005 magnum rt w/5.7
bought the car needing an engine rebuild. no problem, done many of them. dropped valve seats and ruined 2 pistons and 1 head. prior to me buying it, it also sat for a long time. that made me concerned that I would get all the work done and fire it up and find out the lifters were stuck/collapsing. so I figured i better replace them. then I made a poor judgement decision. the cost of lifters made me settle for some cheap ones (dont even ask what brand lol), just assuming ill be alright, the reviews were good! lol. engine ran fine for a while about 1000 miles. then one day my friend borrows it (a friend i trust who wouldnt do something stupid) and half way through his day with it he said it started make noise, getting worse. when he dropped it off to me it was super bad rapid tapping bad lifter sound. super frustrated. so I couldnt even get to hear the progression of sound, just came back to me like that.

anyways, I pulled both valve covers, assuming, the noise is so bad that it should be obvious, if nothing else, one of those cheap lifters that I am going to regret buying. but ZERO lash or movement in any of the rockers. rotated the engine all around to different positions, zero lash. had someone crank it while watching lifters and valves, everything operating as it should with no obvious faults. I figured oh no, maybe its a rod bearing. didnt sound like that, but im not an expert. checked the oil, ZERO metal in the oil. super clean. but I pulled the pan anyway. none of the rods have any movement in them, at all. just a little bit side to side as normal. checked timing chain with the pan down, chain is tight also

so this is frustrating, cause I cant even find the problem, yet sounds like it should be so obvious. question is, can the lifters be collapsing only when there is more pressure on them? like when the engine is running? I am thinking that is what might be happening. also, this does have MDS shut down cylinders. id like some clarification on how that works. I am pretty sure the solenoids provide oil pressure to the specific lifters and that causes them to 'collapse' and shut down the cylinder. I have no codes or anything. I dont think that is an issue since my noise comes immediately right when you turn on the car. possibly one of those shut-down lifters is stuck collapsed?

my thoughts are, just for verification...I will assembly the engine as much as necessary to start it, but with valve covers off, and have someone start it while I try and hear/see the noise, maybe which side it is on, at least (I realize they will be moving very fast and hard to tell) and when helper shuts the car down, immediatly check all rockers for any lash/movement. maybe from them sitting over night they have sprung back open and that is why there is no lash now.

any other thoughts or tips or things to check?
also, If i am into new lifters again. any suggestion on an affordable brand? I would like to maintain MDS

 

EngineTech for the win! lolololololol
Ok, I have this very car. So lesson 1 you've already learned, don't cheap out on engine components. So the MDS cylinders are strictly 1, 4, 6 & 7. The 4 solenoids feed those 4 cylinder's lifters. Default position is off. PCM engages solenoids to collapse the lifters, which then trap gas left in those cylinders as a kind of air spring (so as to offset not having combustion to push the piston down again) and the injectors are shut off to those specific cylinders until MDS is disengaged. It's possible your cheapy lifters may not be pumping up properly. Also ensure you didnt' mix up the intake and exhaust pushrods.
I cannot stress this enough, there is no "affordable brand" for lifters for these engines. Want it to survive and/or not have to do this again any time soon (especially since lifter replacement involves pulling the head)? Only two real options, the latest part number revision OEM (factory) lifters or Johnson lifters (which are EXPENSIVE).

 

No, I did not buy enginetech lifters first time, worse than that. They seemed like a better choice the second time around, you are saying enginetech is NOT a good brand? lol. like I said, Ive done many engine rebuilds before, so I know better. i was just so far in over my head already in this vehicle, double what I thought, so since it was my own car I figured I would chance it. I also wonder if some debri could have gotten stuck in it. like I said, previously it beat holes in 2 of the pistons, so some debri went around. I cleaned everything out as best as I could though (wasnt too bad as far as metal/debri goes)

so what are your thoughts on my diagnosis path? I just put my oil pan back together last night. was gonna put some oil in it and fire it up without valve covers on to try and pin point whats going on. think its possible that the lifter is only collapsing under more pressure like when it is running? (no, did not mix up pushrods)

can I get a link for the johnson lifters that I would need for this car? I searched their site but wasnt sure I was looking at the right stuff

Im tempted to put the factory ones back in that had 200k on them lolol. even though I did not hear it running at all with them in.

 

Ok, so I just let it run for a few seconds with the covers off so I could observe, then check lash/lifters. this the only one that I found that had any movement. enough to make some noise Id say. then next time i tried it, it had no lash. so it must be something that just happens under more pressure of the running engine. junk lifters. one other one on the other bank barely had a little up and down wiggle room at one point too. then next rotation it had none. let me know if the videos work. I guess lifters it is.

hey just want to let you all know, dont buy junk lifters lololol

 

Well if you're trying to keep MDS then you can't use Johnsons. You want the latest part number revision Mopar.
Can't check them that way because you don't know when any of those cylinders is at TDC and there's supposed to be a little wiggle vs any other position where the valve is under spring load.

 

I dont think I should be able to lift the rocker that high off the valve though, probably 1/8th inch almost. none of the other ones did that. and I rotated the engine to different positions, by hand, so I was checking each rocker with the lifter on the bottom of the lobe (low spot, not high spot on lobe, so no pressure on lifter).

regardless, confident that is lifter issue, though?

 

New mopar lifters for the win! or loss......ughh!! lol. oh well. working and sounding good once again!