Valve lash keeps getting loose

[Garys1969RR]

I poured the oil thru a strainer with a magnet in it, and again, no signs of any metal particles. Anywhere. Just slightly darkened oil.

 

[Fran Blacker]

I agree, metal particles are damaging to an engine. I have the engine partially disassembled, and have not found any signs of metal particles. I've checked the lifter valley closely, and nothing there. The only thing I've found is slightly darkened oil. I'm going to re check the oil I drained out and see if I can find anything. I appreciate your concern.

Any chips would be in the pan pickup screen would stop big chunks and the filter would almost all other crap. If you can cut oil filter without out putting debris from cutting it would give you some info. Could remove oil pump and clean and inspect for piece of mind, if you haven't gone crazy yet?

 

[Garys1969RR]

Any chips would be in the pan pickup screen would stop big chunks and the filter would almost all other crap. If you can cut oil filter without out putting debris from cutting it would give you some info. Could remove oil pump and clean and inspect for piece of mind, if you haven't gone crazy yet?

Yes, I think that will be my next step, remove and inspect the oil pump. Never had much luck taking oil filters apart, very messy. I only drove this a few miles after the problem started.

 

[Fran Blacker]

If you know some with a large pipe cutter, there you go or rent one.

 

[moper]

Hint- you won't be able to see those particles. Doesn't mean they are not there, or that you'll be able to see them. When you figure out how to inspect the piston skirts, and ring lands, and oil passages by looking down from the top, let me know.

 

[miller]

But a teaspoon full of cam lobe and lifter inside an engine is no problem? Slap in that new cam and go for it.

What teaspoon full?
Photos show slight scuffing on the cam lobe...no 'missing metal'. Tappet surface slowly caved-in, changed shape, again no 'missing metal'.
First, I was looking at parts getting 'ground down'...not what happened.

 

[68 HEMI GTS]

Here's my thoughts, will you put it back together and it'll run? Yes it will but, Here's how I look at this. if this were a low performance worn out 350 chevy in a pickup truck, I'd slam another cam in and call it a day. It's been done before and it'll be done again. Being a high performance motor that you plan to beat on, and expect results I'd tear it down. Metal from wiped cams goes everywhere. It really likes to imbed in the piston skirts and scratch the cylinders. Only way to get it out is with a small pick or glass bead the skirts (at least those are my methods). It also imbeddes in the bearings, and it ends up in other places you don't want it. It doesn't matter that it only ran for a "little bit", use that to your advantage while the damage is minimal. Only way to really clean the motor is a full disassembly and cleaning. Several other builders have stated the same thing. It's a lot easier to fix right the first time and will be less time and headache in the long run. You may take it apart and not find much or anything if your lucky but, it's worth the effort and piece of mind (at least it would be for me). Good luck

 

[moper]

What teaspoon full?
Photos show slight scuffing on the cam lobe...no 'missing metal'. Tappet surface slowly caved-in, changed shape, again no 'missing metal'.
First, I was looking at parts getting 'ground down'...not what happened.

How many cam failures have you personally taken apart? Just so I'm clear - your assertion is the hardened almost flat end of the lfiter, bent up into the body? And the cam lobe just got a little scuffed?

 

[miller]

How many cam failures have you personally taken apart?

Fair question. Answer...a few...mostly hammered motors from previous owners.

One main thought...Gary looks at the cam bearings, and said their in good shape! If all that ground down metal was through the oil system, it would show up! Especially in any bearing surface, anywhere in the motor.
Got one eye open, and just looking at what's there. Look at the photos.
Sure, must look at everything, then decide...just like I'm guessing Gary is doing.

 

[miller]

Maybe not enough answer.

Previous motor (383) I worked, running, had 9 of 16 push rods bent, four or five caved in tappets like Gary's.
Of course I overhauled the thing complete, that was the plan. But, remembering no 'ground down' parts, getting to ALL the bearings, none had any damage, besides normal wear.
Yeah, I know radials are different animals, but still use some like bearings in them. Seen my share of chewed up/spit out bearings, from loose metal. If it's in the oil, it gets to them.

 

[moper]

Ok. Just wanted to see where you were there. I've done more than a few myself. The issue with the particles is they're very small, and they are combined with oil being flung all over the crankcase. They don't embed into the bearings unless the filter is in bypass mode. That's not supposed to happen unless the filter gets plugged - but some cheapie filters get stuck or the valve doesn't work as its supposed to. They do get into the piston skirts, on the bores, over the cam and oil pump drive, into the timing chain, into the ring stack, and into the valvetrain. All of those areas can suffer damage should that stuff stay there long enough. If the engine is run enough, and the filter plugs or is in bypass, the rest of the oiling system can suffer very quickly.
It's kind of like blowing a transmission and not replacing or cleaning the convertor or cleaning out the cooler and lines. You might be fine. You might not.
Some are willing to gamble success. I'd rather not gamble for the cost of a gasket set, cam bearings, and freeze plugs.

 

[miller]

It's kind of like blowing a transmission and not replacing or cleaning the convertor or cleaning out the cooler and lines. You might be fine. You might not.

Agree 100%! Though it's also a matter of tossing a couple big handfuls of common sense into it. Probably why I mentioned dropping the pan, and #4 main cap, for a looksee. It seems he's taking the right steps to be sure of things, and it's still a matter of choice. One thing I highly recommend to anybody is...make damn sure your sure. Just takes looking at the right places.

I'll make this short, but your statement reminds me of an R-3350 (B-29 motor) that went south. That motor was 45 years old, but brand new, never run! Needed going through complete...just because. Rebuilt, ran it on test stand 5-6 hours, including 2 TO RPMs...ran perfect.
CAF got the motor, slapped it on, and went for a photo shoot around the field. Engineer started telling flyboy it was overheating...naw, want more power! Motor burned smooth up, before they got on the ground. CAF wanted us to replace it! Nope.
Later, 3 members, 2 that I kinda knew, flew up to the shop. They wanted to tell me what 'really' happened. Uses an oil cooler for each motor, with several feet of oil hose. Cooler was kinda flushed, not the hoses...end of story.

 

[Garys1969RR]

Drained a little oil out of the oil filter by pushing the anti flow back valve (rubber flap) open with a small screwdriver. Drained it onto a paper towel, and still couldn't find anything other than 2 tiny pieces of what looked like dried black RTV or gasket material. It was soft and I still couldn't see any metal fragments. But the oil is quite dark. There was only maybe 4 miles on the oil. So I'm thinking that the metal that came off the cam lobe, (.120" off the top) may have been suspended in the oil. Visualize an oil covered lobe passing across the lifter bottom. I'm fairly sure there were tiny sparks as the molten surface of the lobe broke through the oil film and moved across the lifter. Due to the polished appearance of the lobe and lifter contact surfaces, I believe the small amount of material removed came off in micron sized particles, much as a buffing wheel polishes metal. It was then distributed throughout the oil system, the particles being so tiny that they passed right thru the filter element. So I think the missing metal from the lobe came out with the oil. Maybe wishful thinking, as I'm not an expert in metallurgy. But again, I have found no trace of any metal particles. With the old cam out, I can actually see the bottom of the piston skirts at BDC, and I see only clean aluminum. I don't think there were any grit sized pieces of metal in there, or the cam and lifter would have some pitting in them. Compression is still real good, I can hear the air barely seeping past the rings when I slowly rotate the crankshaft. I guess time will tell.

 

[Garys1969RR]

Also, I replaced the oil pump with a new one just for good measure. When priming it with a drill, I still couldn't see any particles coming out of the cam bearing oil hole at the front of the engine, or the lifter bores at the front. All the oil came thru there as that is the first place the oil from the filter goes, and there is no cam or lifters in it right now.

 

[GrabberOrange69]

Nice looking Road Runner. Good luck with the new roller cam.

I really hate these newer flat tappets - can't trust them. How many folks here ever wiped a cam in the 1980s? I never knew of one in a MOPAR. Now it seems lots of guys have experienced it.

 

[Garys1969RR]

I have never lost a cam lobe. This was the first. I've ran Racer Brown mushroom lifter cams with .690" lift, and huge amounts of spring pressure, to 7000 RPM, and never a problem. The opening ramps were so fast on that STX-62, that the exhaust note was like a loud popping sound.

 

[miller]

Heck, man, sounds like your doing about all you can do, to make sure. Just for grins, any chance you've run your magnet on the bottom of the pan?
If you had friction inside the motor (like that tappet), making heat, it could turn the oil brown. Anyway, great to hear your not finding any bad news in there!!

Even though I've run across earlier model tappets cave in like that...would be through a 100,000 mile cycle. Can only guess the metal treatments (surface hardening) might not be as good, as they used to be. Somebody getting lazy, or just cheap on making parts.

 

[Garys1969RR]

There is a windage tray in there, so not much access to the pan bottom. But that gives me an idea. I can get a long telescoping magnet and snake it in thru the drain plug hole, move it around and search for metal particles. I may have some access from the timing cover area. Thanks for the idea, Miller! I'll try that!

 

[miller]

Yes, sir...that's what I meant, through the drain hole. If there is any metal, it will probably be on the bottom of the pan. That should always be checked.

Not suggesting...though me being me, ha...on my 69 RR, I used to flush my motor every year. Did that (back when oil was 30 cents a quart) by draining the oil, but leaving the filter on. Two quarts of new 30w, three quarts of kerosene...only idle until tappets started tappin'.
Results...3 years in, got a leaky oil pan gasket. Dropped the pan for new gasket...inside of the pan almost clean enough to eat off of. But, yeah, totally un-needed.

 

[Garys1969RR]

Pulled one of the springs off the new Eddy heads that I had put on before the cam lobe failed, and they are 1/8 inch larger diameter, with heavier coils than the ones that were on the old 906 heads. This may have contributed to the ex lobe going bad.