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Anything new on the clattering lifter front?


NAXJA Forum User
I put in a used junkyard engine about 18k ago. I was in a bind, low on cash but the original engine was completely shot. So I took a chance on one with a basically unknown history. Pulled it from a 99 grand but it has a build date of 96 so obviously came from somewhere else. donor was beat hard but i was told it ran when the trans shot. Pan did not have a lot of sludge in it, so I re-sealed everything, put it in and crossed my fingers. Lifters clattered so bad it sounded like a diesel on start up but it pretty much eventually went away at running temperature The engine has no blow by, does not use any oil and runs great. But the start up lifter clatter just won't go away no matter what I try. I'm running Rotella and change it early most changes, and I've run seafoam through the oil a couple of times. Has anyone had any luck with anything else? As long as its still running good I'm not going to risk screwing something up by pulling the head to put new lifters in. Oil pressure is great, 60 at road speed, 25-30 at idle on a 100 day running mail.
You have hydraulic lifters. I don't think they are very expensive. They are shot if they continue to rattle on start up.

Less than $50 for a set. Then there is the gasket and effort. While your at it you should also replace the seals..
Try duralube. You can get it at Walmart. I ran it in a wj to quiet lifters at startup. It was the only thing that made a noticable difference that I tried.

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Six40150, seals have all been replaced. It doesn't leak a drop. I know lifters are cheap, but in my experience if I try to fix a minor annoyance on an otherwise perfectly running engine I am more likely to cause a larger problem.
Tjmotter, I just changed the oil but marvel mystery oil would definitely be worth a try, used to run it as premix in my 7, a lot of rotor heads swear by it.
my buddy replaced his cracked xj head, and decided to replace the lifters just cause it was easy to do with the head off. Big mistake. despite ample amounts of break in lube used, the lifters were ground down, and the cam lobes ground down within 100 miles. sometimes new lifters and a used cam dont wear in very well. his new lifters, one of them had near a 1/4 inch ground off. the lobes on cam went flat.

beware of putting in new lifters on a used but still good cam.

You can have your lifters rebuilt, cleaned out as needed, just besure each lifter gets put back in the same bore it came out of, dont mix them up!

on a van I habe I got horrible lifter clacking on start up, it would clack for a mile then quiet down, this happened right after I did an oil change. I bought a cheap fram oil filter, big mistake. it back flowed during shut off such that on start up it took a while for the filter to fill up and get enough high pressure oil to the lifters. as when I replaced the filter with a better brand an OEM brand filter the clacking went away, no more clacking on start up.

so this could be as simple as a bad filter with a failed backflow valve or something like that, change the filter and see what happens, also the Marvel Mystry oil trick is claimed by many to help, depending on the cause, it can help if the lifters are a bit gunked up.

Id avoid replacing the lifters with new, unless you do the cam at the same time. but the lifters can be removed, dissassembled and cleaned, just put them back in the exact same bore and they will be no excessive wear problems.
I always use the mobile one 301a, so I doubt the filter is the problem. I have my old engine on the stand awaiting a full rebuild if funds ever materialize for it. As much trouble as it is to put a cam in these things I think I'll try the MMO next oil change, otherwise continue delivering the mail as usual. Coming up on Christmas I dont have a bunch of down time for in depth repairs. I forgot to add in my original post that I had tried Lucas too with no change.
Well, I went ahead put in the mmo and now that im coming up on the next oil change I can say that in some respects it may be a hair better, but in one its way worse. Now I drive to work, about 10 minutes, case the mail, about 2 hours, then when I leave to serve the route one lifter is way worse for several blocks. Like rod knock loudness but valve speed and seems like its coming from the cylinder 4/5 valve cover area. Should I try seafoam again or maybe Lucas, or maybe the thinner synthetic Rotella? I would try the diesel clean out but not willing to take the risk on my work vehicle.
Nothing will be gentler and thorough as the MMO. Time to pull the valve cover? At least shine a light through the oil fill hole and assess the sludge situation?

What oil filter are you currently using?
Mobil 301. Carbon should be nothing, cleaned it out when I put it in and it uses no oil and has no blowby. I know I really should pull the cover but I sealed it with the right stuff and the possibility of damaging that cast cover is real with how hard that stuff grabs. Also it would be several hours of cleaning gasket surfaces for re install. Don't really want to get that far into it until after the Christmas season.
What about one of those USB-on-the-go cameras that hooks to your phone and acts like a borescope? cheap on eBay and could just run that in the oil fill port for a look around without pulling the cover...
I'm going to try changing the oil this weekend with t6 rotella 5w-40 instead of the 15w-40 ive been using. Maybe the thinner cool weight will flow into those clogged lifter ports a little better.
Oil did not help, but searching through the net i think I've diagnosed it as piston slap. Going to go back to the heavier rotella but I think with these colder temperatures im just going to have to hope it holds together through the Christmas season, and finally start rebuilding my extra motor.
What about one of those USB-on-the-go cameras that hooks to your phone and acts like a borescope? cheap on eBay and could just run that in the oil fill port for a look around without pulling the cover...

I have one of those. It's damn near useless and won't focus on anything closer than a few inches. The light on them only lights a few inches down a pipe too.
Ah, good to know, thanks.