Cam lobe going flat...what now?

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sbh126

sbh126

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I’ve had a lifter tick ever since my engine was new. I did all sorts of adjusting and never could get it to go away. I finally bought a second set of Comp lifters and replaced them. I used Camshaft Lube, Break in additive, and assembly lube all from Comp. I fired the engine and ran it between 2000-2500 RPM for 30 minutes as per break in instructions. It sounded great when I let it idle following break in. Finally no tick. I then removed the valve covers to replace the inner springs and everything looked good and tight.
The following morning, I let it warm up and took it on a short drive. A few miles out I started to hear a rattle so I turned around. By the time I got home the rattle had turned into more of a knock. Tore it apart to find what felt like .050” lash in my No 6 Exhaust rocker.
With the headache I’ve had with hyd flat lifters I think I am planning on making the change to a solid roller cam. I don’t mind the noise or the additional maintenance. I have two questions;
1. Given my combo, What recommendations do you all have for a cam for my setup? I had a .545 lift cam and I’m not sure if I can handle any additional lift.
2. What kind of clean-up is required prior to stabbing a new cam in? The Marine Corps has me TAD to Florida for 6 months away from my garage and many of my tools so I’m really hoping to get by without pulling the engine. I’m hoping I caught the problem early enough to prevent further damage. If the cam bearings aren’t damaged can I assume the main and rod bearings are good?


My setup is as follows;
Rebuilt 440 with 1300 miles on it.
70' forged crank and reconditioned rods
KB 237 forged pistons
10.6 compression and running on 93 octane
Stealth Heads w/ adjustable 1.6 rockers
Comp 924-16 springs
Eddy RPM dual plane intake
Atomic EFI system
MSD 6AL2 ignition
1 7/8" fenderwell headers into 3" exhaust.
3.55 rear 8 ¾
4 speed A833
 
sbh126 said:
2. What kind of clean-up is required prior to stabbing a new cam in? The Marine Corps has me TAD to Florida for 6 months away from my garage and many of my tools so I’m really hoping to get by without pulling the engine. I’m hoping I caught the problem early enough to prevent further damage. If the cam bearings aren’t damaged can I assume the main and rod bearings are good?
Click to expand...

I would drain the oil and look at it. Pull the oil filter and cut it open and inspect carefully. Then choose a course of action.
 
If you take the rockers and pushrods out, you can reach down with a hooked piece of wire, (welding rod) flattened at the end, and snag the lifter C-ring groove where the end-gap of the c-clip is, if it's a fresh lifter, it'll pull right out, and you can use a magnet to pull the lifter up thru the gap between the head and intake, (may require loosening one intake bolt that protrudes).

You will then be able to determine if the lifter's collapsed, or by looking at the bottom of the lifter for signs of wear..

You then may be able to inspect the lobe thru the lifter bore, and if it looks good, slide a new lifter in, and cross your fingers..

This method works for replacing a noisy lifter without taking the manifold off.

If the lifter is fresh, but difficult/unable to remove, may indicate bottom of lifter damage, or on older engines, shellac build-up below lifter bore.

hope it helps
 

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inertia said:
If you take the rockers and pushrods out, you can reach down with a hooked piece of wire, (welding rod) flattened at the end, and snag the lifter C-ring groove where the end-gap of the c-clip is, if it's a fresh lifter, it'll pull right out, and you can use a magnet to pull the lifter up thru the gap between the head and intake, (may require loosening one intake bolt that protrudes).

You will then be able to determine if the lifter's collapsed, or by looking at the bottom of the lifter for signs of wear..

You then may be able to inspect the lobe thru the lifter bore, and if it looks good, slide a new lifter in, and cross your fingers..

This method works for replacing a noisy lifter without taking the manifold off.

If the lifter is fresh, but difficult/unable to remove, may indicate bottom of lifter damage, or on older engines, shellac build-up below lifter bore.

hope it helps
Click to expand...

No such luck.
 

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Yessir, that's an issue. Probably would be complete teardown / full bearing inspection time. That much debris running around in the system is bad news. Sorry to see it, but at least you have a course of action.
 
I was able to extract even varnished /6 lifters with a magnet and CLP...Semper Fi!
Cpl. S. Wander, Weapons Co. 1/9 0351

PS>> just saw results. Roller....but be prepared for an $800 bill.
 
Bad Sport said:
Looks like more than one is bad, unless I'm seeing it funny.
Click to expand...

It might be the light. It does look different in the picture. All 15 other lifter bottoms still have a smooth machined surface. I'll post better pics when I get it out.
 
Sounds like inertia has done this before...a few times. Sbh126,some cam companies advertise treatments for their cams to address this. I have never used them (treated cam)but maybe someone else has on this forum and can let you know if thats a viable option.
 
Tell ya what I think. Drove straight home and shut it off. I feel there is a very reasonable expectation your 440 is fine. Maybe just a oil pump. Because a good filter will catch that trash and hold it. Anything small enough to get through is going to be small enough to cause no harm. Especially as quick as you were on it. Thats the way they are designed to work. Now if you cut open that filter and found nothing,then it might be time to start wondering.
 
Am I wrong in my thinking that the only oil that goes the the filter is bypass oil?
 
.545" lift, eh? XE285HL? Comp Cams? Note.......the lifter is wider than the lobe face. So.......Good bet there was nothing wrong with your break in process. I have found many flat tappet Comp Cams over the past few years where the casting flash between the cam lobes hasn't been removed and the cam grinding process isn't wide enough to grind the flash so that the width of the lifter clears the flash. I used to send the cams back........and get a new one the same way. I've taken to inspecting each cam and grinding the flash between the lobes with a die grinder and a thin 3" diameter cutoff wheel.
 

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Dang, that is good to know. Send that pic to Comp and ask WTF?
 
Do you know if your connecting rod bearings shells have oil squirt holes??

I have a theory that a lotta lifter/lobe failures are because folks use the later bearing shells used with the newer roller tappets, that don't have a squirt hole and they don't spray oil on the cyl wall and cam lobes like the old shells with the squirt hole (which are still avail).

I believe the squirt of oil from the connecting rod is nec on flat tappet cams. just a theory

So if you use the newer shells, I always notch the shells where the oil hole's supposed to be, and I've never had a lobe failure yet, ( I'm sitting on wood here, lol ).



hope it helps
 
I drained the oil and ran a magnet through the bottom of the drain pan and got almost nothing. There were a few dust like particles but nothing I would be concerned about. The oil coming out of the filter had a definite metallic sparkle but no real chunks. I haven't cut it open yet to see though.

I'm about to pull the oil pump and see how things look. I've got to make a trip to autozone first to rent a damper puller. I'll probably replace the pump just out of principle.
 
inertia said:
Do you know if your connecting rod bearings shells have oil squirt holes??

I have a theory that a lotta lifter/lobe failures are because folks use the later bearing shells used with the newer roller tappets, that don't have a squirt hole and they don't spray oil on the cyl wall and cam lobes like the old shells with the squirt hole (which are still avail).

I believe the squirt of oil from the connecting rod is nec on flat tappet cams.

So if you use the newer shells, I always notch the shells where the oil hole's supposed to be, and I've never had a lobe failure yet, ( I'm sitting on wood ). jmo

hope it helps
Click to expand...

I'm honestly not sure. The rods were factory forged rods that were reconditioned. If I pull the pan I'll check.
 
OP. For your consideration

During my career, I've replaced cams with worn lobes in dozens of cars of all breeds. Dealerships won't pull an engine apart for a worn lobe, but will maintain the warranty for duration, cuz motors generally aren't noticeably affected by the failure's debris.

It just isn't practical to tear down every engine that eats a lobe. Having torn down engines with worn lobes, I never did find any debris other than grey paste in casting depressions..

I have maintained some of those lobe eating cars for decades, and never had a failed lobe debris issue.

Have faith in gravity and the oil filter.

However that's not to say pulling the pump isn't a great idea.

jmo . . hope it helps
 
IQ52 said:
.545" lift, eh? XE285HL? Comp Cams? Note.......the lifter is wider than the lobe face. So.......Good bet there was nothing wrong with your break in process. I have found many flat tappet Comp Cams over the past few years where the casting flash between the cam lobes hasn't been removed and the cam grinding process isn't wide enough to grind the flash so that the width of the lifter clears the flash. I used to send the cams back........and get a new one the same way. I've taken to inspecting each cam and grinding the flash between the lobes with a die grinder and a thin 3" diameter cutoff wheel.
Click to expand...
Sucks to hear this. I've been running COMP products since the 80s and never had a quality issue until I bought the last cam in 2013. Three bolt solid roller. The issue was that the cam sprocket bolt holes were tapped fine thread instead of the coarse threads it should have had. I called COMP and they blamed it on the company that produces the cores for them. I asked if they QC them and the reply was yes. A little back and forth with them and I was left wondering if they missed something as obvious as that, how good is the QC at COMP? Once these company get bought out or turn into a conglomerate quality takes a back seat to volume and profits.
 
IQ52 said:
.545" lift, eh? XE285HL? Comp Cams? Note.......the lifter is wider than the lobe face. So.......Good bet there was nothing wrong with your break in process. I have found many flat tappet Comp Cams over the past few years where the casting flash between the cam lobes hasn't been removed and the cam grinding process isn't wide enough to grind the flash so that the width of the lifter clears the flash. I used to send the cams back........and get a new one the same way. I've taken to inspecting each cam and grinding the flash between the lobes with a die grinder and a thin 3" diameter cutoff wheel.
Click to expand...
That pix shows an amazing small distance between the base circle and the casting. Thanks for the info, IQ52. I have never seen such a thing on any cam.
 
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