I've got a stock /6 from '69 that has spent a fair time (35+ years) sitting in a garage.
I've been diagnosing bending push rods on the 1,5,6 intake valves for a bit now.
So I pulled the head and those valves were stuck tight and the seats full of thick sludge.
I've kindly received a new, built, clean head from the Legendary Lou Dart270 and was ready to drop-in replace.

But upon the final inspection, I noticed that the lifters for those exact valves were stuck "lifted/up".
I sprayed some Kroil and got them loose and spinning freely when spun with a needle nose.
I spun over the engine a bit and noticed that a few of the lifters were either rotating very slowly or not at all - including some of the ones that weren't even stuck prior, and that spin freely when rotated manually. All lifters moved up and down as the engine cranked, but some just wouldn't rotate at all during the up/down motion.

So, I tried to pull one of the offending lifters (exhaust cylinder #1) with a needle nose by its top "lip" a few times - and it rose, but only a few mm higher. THEN I took a break, and came back to find that I must've gone at a bad angle earlier or something; because the lip was cracked! There were some metal bits hanging out in the valley area that I had to pull out with a magnet at risk of having them drop through the oil hole...

A few questions and open to additional comments:
1. Anything more I should consider investigating due to the lack of automatic lifter spinnage-on-crank?
2. I assume I should be replacing (at least) that cracked lifter. What is recommended in terms of the replacement? And should I be replacing them all once I'm at it?
3. Is freeing the remaining lifters as I had done above (Kroil method) enough to button up and continue installing the new head?

If it were me, I would try to knock/file/sand down the cracked/high spot on that lifter and put back where it came from. If the cracked part has a piece that is easy to break off, do that. If you put in a new lifter, you will have to break in the cam again or risk wiping that lobe. Just because the lifters are gunked does not mean they won't rotate or go up and down. The valve spring pressure will push them back down even if they do not fall back down after you pull them up. Flood the top of the lifter valley with oil before you put the valve train back on and the valve cover back on.

Lou

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Home of Slant6-powered fun machines since 1988

Thank you for your comment, and thanks again for the head

Isn't it a shock that the lifter chipped under hand pressure though? And if its integrity wasn't already weak, I can only imagine what would potentially happen under valve spring pressure at operating RPM... Is that a concern?
Apologies, I don't think I understand. Do you mean that I should pull out that cracked lifter and shave down the top lip so that it's all even again?
The photo may make the crack appear more shallow than it actually is, but my eyes could also be deceiving me - so what if I pull it out and the crack is over a mm deep? Still would be okay to shave?
I've confirmed that after some Kroil-ing and moving, all of them now go up and down - but some don't rotate/spin at all when cranking (while others very clearly do or at least slowly).

I am surprised you can see any of them rotating just cranking.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Lifters are a hardened metal. This means that they are brittle in some ways and very durable/strong in others. The surface treatment/hardening will make the wear surface fragile to some damages. But installed all of the force is spread out across the bore of the lifter. There is almost no angle to the valvetrain of the slant pushrods so it should be an issue.

I do believe that you are being instructed to file off any high spots on the damaged lifter and reinstall it. As long the diameter doesn't have a high spot it should not cause any problems at all. If the break caused a high spot, remove the high spot.

If it was my engine I would pull all the lifters (don't mix them up) and give them a good cleaning. I would also clean the bores and wash every thing with a good solvent rinse followed by good motor oil or assembly lube. If you don't have the oil pan off you probably should for getting that Kroil out of the crankcase.

Here is a better angled pic of the damaged lifter.
Ah, I thought at first that filing the "high spots" means shaving the entire circumference around the top lip area to get it down to the lowest level of the crack...
But I may understand now - it means there are some high spots that form as a result of the cracking... And you mean it's not somewhere on the top of the lifter, but rather only accessible/detectable after pulling the lifter, that'd appear along its sliding cylindrical surface. Correct?

If so, how do you suggest I remove the lifter - being that my last attempt resulted in the cracked lip
It comes up a few mm if I pull at it but then won't come up more at all. Keep on pulling harder, perhaps with two pliers from each side?

Those lifters do not look badly sludged at all. I would definitely leave all of them in there and not mess with them. You will only see the lifters rotating when the engine is running. It is very common with old/worn engines to not be able to get the lifters out from the top. Best to leave them alone.

I would call that lifter chipped and it is probably perfectly fine to run as is. If it moves up and down easily in and out of where it is in your 2nd pic where the top sits below the lifter hole edge, then you are good to go and you don't need to remove any high spot. Put it all back together, adjust the valves properly (FSM procedure - engine off), and start the engine. Set it at a high-ish idle like 1200-1500 RPM until oil comes up to the rocker assy. After you verify that oil is reaching the rocker shaft and arms (may take a minute or so at high idle), then look at each pushrod and lifter and you should see them rotating.

Keep it simple, make observations, carefully assemble things, and report back to us. You should get this running again just fine.

Lou

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Home of Slant6-powered fun machines since 1988

My son has a 318 on a stand that he pulled to inspect the bearings and replace them all including the cam bearings. Input the cam and lifters in this engine about 75k ago. It had started knocking on the bottom end while running. We found out the #3 rod bearing was "chunking". . The bottom of the lifters had a buildup of sludge on them that wiped right off with a finger once the lifters were out but there were 2 that we fought trying to pull out the top I don't have one of those "lifter puller" tools. Never needed one.
We could move it easily in its normal range of travel but couldn't quite get it out. We ended up pushing it up as far as we could get it to where it "stuck", pulled the cam out and then popped them out the bottom.
We were glad we had pulled it to check the cam bearings as they had a lot of"chunks" out of them. Back when I put that cam in the engine , which was done with the engine still in the original truck it was born with, the bearings were perfect. That was back in around 2008.
That said when I built my last /6, the brand new ones (I forgot whether it was rods or mains) looked the same way when I took them out of the box to put them in... I set them aside and bought another set. This was 4-5 years ago already. I had posted pix back then asking the experts here what they thought.. must have been an age thing with those bearings. They were brand new but 40+ years old at the time.

This may be a "zero-value" post, as it's just my opinion, so disregard as desired.

• Dear God, don't pull out lifters with a pair of pliers. Use a valve lifter puller, as seen here (link may die one day):
  
  This one is listed for $13.
  
• If I were in your position, I would not be able to resist pulling the lifters just to "clean them up" a bit. (No, I am not under any illusion that "cleaning them up" would actually affect anything). I would NOT disassemble them, as then they will have to re-pump with oil, but I would remove crud. I have found SeaFoam is actually pretty darned good at cutting / dissolving varnish and carbon in engines, and I'd be inclined to use that to free them up in their bores.
• I would pull out the cracked lifter and just dress the sharp edges of the crack with a stone where they bear on the bore. It should only take a minute.

But, if you just left them in there like that without touching them, they'd probably be fine, too.

- Eric

I think these are solid lifters, and I'm not sure that special tool will work unless you have the little clips on the top of the hydraulic lifter to grab onto.

Lou

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Home of Slant6-powered fun machines since 1988

Crap. Didn't think of that. Never had the lifters out of a \6.

Of course, they're solid lifters, so no oil, no disassembly, no nuthin'.

Now I'm curious whether they have a ridge for a tool to grab.

But yeah, not much to do with them.

I'll just keep my mouth shut.

- Eric

Excellent - thanks all.
Getting back to reassembling

Neat.
Connected all back up and oddly, got zero compression across all cylinders. Was thinking the worst, but it turns out to have been mixed up valve lash/rocker arm placements. The valves were never fully closing!

Loosened each rocker arm "by ear" up at TDC to get it going at the least - and alas - it started right up!
After a couple minutes at high idle, oil dribbles everywhere and pushrods spin, albeit some slower than others. But they all spin now.
Tapping the gas to kick down the choke and slow down idle at operating temp, it's definitely misfiring on at least one cylinder.
I will warm the engine back up and set the valve lash to-spec this time.

I'm hoping it's just that or perhaps the idle mixture adjustment which I never had a proper chance to set prior.
Cheers

Sounds like great progress! Good job diagnosing the "valves held open" problem and adjusting by feel/ear/eye first. That is a signature you can think independently and solve mechanical problems. Once you set the valve lash, likely your misfire will go away.

Interested to hear more progress. So glad that my old cylinder head can bring new life to another Slant 6!

Lou

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Home of Slant6-powered fun machines since 1988

Good progress!
I dab a spot of white paint on all my push rods to make it easy to see them spinning

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6