Cam Bearings on 77 440 - Loose Flakes

Putting my 77 440 back together - just replacing normal wear items on a good running engine. The lifters were showing wear, so I decided to install a new Summit cam & lifters. Was about to install the cam tonight, but saw what looked like bearing material flaking off of the three center cam bearings. Most of the flaking is near the oil passage, but not always:
1977_440_Cam_Bearings by clair_davis, on Flickr
1977_440_Cam_Bearings by clair_davis, on Flickr

So what causes this, and how long does an engine run with this going on? I bought the engine installed in the 77 NY'er it started life with, and the engine seemed to run fine. Are pieces of bearing material going to keep flaking off, or is it a localized thing? Why only the three middle bearings? I've never seen anything like this before...

Thanks,

Clair

Replace all five of them now, that damage is either from heat or corrosion
I install my own, I install the rear one first and then test fit the cam into it, if it fits fine and spins fine I do the next one and so on
If it or another one doesn't fit and spin easily I fixed that one before installing the next one and so on
Good luck, let us know your results

I've had that happen with a '67 440 too many years ago. It was the front bearing that showed this.
Thought it was maybe too high constant oil pressure or a too tight timing chain perhaps.
Never looked any deeper into it.

I thought I'd seen it all....
That has to be a manufacturing fault. No "normal" cause of failure would have done that.

do you leave the old ones in and remove and inst. them one at a time?

Is the cam bearing job one that can be done with the crank/rods/pistons in place? I've got the engine on the engine stand now, and no problem setting the short block on the floor to do this job, but I REALLY don't want to take the bottom end all the way apart.

FWIW, I was warned to watch out for "exploding" cam bearings, particularly the front bearing. Neither my 68 nor this 77 had problems with the front bearing - I haven't checked the other bearings in the 68, but will take a look.

Now to see where I can rent the bearing tool and get the bearings on the way...

If the bearing bores in the block were too small, would something like this happen if the bearings were forced in at original assembly?

Thanks!

Clair

The bearing are forced in so they dont
spin... I use a old cam that has been in
about 10 engines to size the bearings..
never had a failure.. I use my impact to
spin the old cam with oil

Do it Cab's way. Otherwise you won't know which one is the tight one.

I knock all the old ones out first and then clean the holes thoroughly and then test fit each bearing on the cam before installing them

OP, on installing them with the bottom end in, take your time and use the alignment tapered tool on the front hole to get all the other four centered and square to the block first and then drive them in Make sure to align the oil holes with the block also
Let us know your results

Bearings and installation tool on the way... had to buy one because there are none to rent locally. Hopefully I'll get a few uses out of that tool in the next few years... will post more pics as I get this sorted out.

Clair

I've seen it countless times....... And worse.

Looks like it had some glycol antifreeze run through it.

Kevin

Ditto.

A friend had a 400 of unknown origin that he wanted to throw a cam in. It was running but weak when we pulled it apart. The cam bearings looked even worse!

While I'm waiting on parts, is there any way to clean out any of the oil passages or other oil-related items? Or is that even worth messing with? The valley and crankcase area have something that looks like a coating of crud - light, but not as clean as the 68 440 was. I assume that the oil passages are cleaner because they were always full of liquid oil, not oil vapor, blow-by, condensation, etc. Cleaner is better, but I don't want to spend time on something that won't be a benefit.

Thanks,

Clair

Had a ‘76 440 years ago that had cam bearings like that, all were touched, some worse than others. I HAD to get it together ASAP and didn’t have time to buy cam bearings, install tool etc. My super greasy solution was to get a two part epoxy that was made for oil (can’t remember which one) filled in the chips, let it dry, knocked down the high spots with a 1/2 moon file, and slammed the old cam in and spun it a bunch of times til it felt decent. Jammed in a new cam and away I went lol. Hate on me all you want but it ran fine and had good oil pressure. I figured the epoxy was probably around the same softness/hardness as the Babbitt they use in bearings so why not!
Obviously if you have time replace the bearings, but if your stuck in the middle of the desert and happen to need a cam bearing fix and have some epoxy give it a whirl

Have mercy... Been working on this for 4 hours now, got the old bearings removed, and have two new bearings installed. #2 bearing is the one that feeds the rocker shafts, and after two attempts, I can't seem to get the holes in the bearing to line up with the holes in the block. One hole is nice, the other is offset enough that the view down the feed tube in the block looks like a football - only about 1/4 of the area of the hole is available to feed oil up to the rocker shaft.

How big of a problem is this? I've heard of folks restricting flow to the rockers in some situations - I doubt that this was one of those situations...

I compared the old bearing to the new, and I'm pretty sure that it's operator error that is keeping the holes from lining up. Maybe the holes weren't lined up that great from the factory, but I had no reason to check that before now.

Sure would be nice if all three holes in the bearing were oblong like the one at the bottom.

4th time was a charm - got the bearing in with the holes lined up much better, and the rest went in without much stress.

Cam won't install all the way now, even though the bearings all checked pretty loose on both the old cam and the new cam. Crud.

Will try again tomorrow when I'm no so beat. Maybe I'm just not holding my mouth right or something...

Did you try installing the cam after each new bearing was installed ? If not that is worth doing in the future.
I wouldn't even think of trying to install any cam bearing in the motor with the crank and rods in it in the car, I'm thinking you are doing that Good luck, you will get it done, keep after it
Maybe see if you can come up with a old cam and use it to fit the bearings in so your cam will slide in decently, you can take a hacksaw and put groove in the cam journals by sawing them all the way across them in a little bit deeper than the cam O.D.
I've never done that so hopefully someone else that has will chime in with a picture or better instructions on doing that
I have and use a bearing knife to fit (scrape them) my bad bearings a little bit at a time, one bearing at a time also
I've never had to fit a cam bearing in a Chevy or Ford block I don't do many of them either, probably around a hundred Mopars to each one of the other brands
Not all Mopars need the bearings fitted, some do and I hate them

Thanks for the encouragement, Cab, this is definitely turning out to be a learning experience...

Fortunately, I'm working on an engine stand and can get to the engine pretty well. I checked the bearings on the old cam and the new Summit cam, and I was actually a bit worried that the bearings were going to be on the loose side. Didn't expect the clearance to tighten up like that, but I'll check things again tonight and see if I can find out which bearing is tight and go from there.

The problem bearing was the one I had to muck with a few times to line up the oil holes. Figures that one wouldn't be done with me so soon. I ended up using my old camshaft as a bearing knife of sorts... Cut a straight groove with a hacksaw and gave it a few turns. Works great, but you have a lot of bearing material to clean out of the tiny groove pretty regularly:
Cam_Bearing_Tool by clair_davis, on Flickr

I ended up cutting three grooves in that journal, and the cutting went pretty well. Probably had the cam in and out of the block a dozen times, but everything turns nice and smooth now, and the bearing actually looks pretty nice.

Now to get the assembly back on track... until the next thing comes up...

Thanks again for all the help, guys!

Clair

Congratulations
A little knowledge, hard work and perserverance pays off again

You basically did as I said by cutting the
slots in the cam.. I cut them about 1/8" deep
maybe a little less but when you spin the cam
it cuts like a knife.. glad to hear you got it.
People that do it for a living do the whole
thing in a minute.. for them time is money..
but thats where I learned it at
EDIT
I use a .040 cut off wheel to cut the slots

for some reason, i thought those slots should be cut on a diagonal ? or doesn't it matter ? i like the approximate 1/8" depth of cut, and i used a .035 wheel.

I really dont think it matters if they are
cut on a diagonal or not.. its to get the
trash out of the way.. I flood it with oil
when I cut so the trash is being removed

A diagonal cut might have some 'self cleaning' properties if lubed properly.
If not it could 'store' more scrapings before needing to be cleaned.

Yes, thanks for that tip, it worked great! I thought about cutting the groove on a diagonal, but I wasn't sure how well I could pull that off with a hacksaw, and I wanted the cutting edge to be straight and sharp. I should have cut the groove deeper, that would have let me cut a bit longer and reduced the number of times I had to R&R the cam to clean the groove out.

Another thing I did that worked well was pack the oil feed holes with axle grease. This caught all of the loose cuttings and kept them from falling down the oil feed. I didn't do this for the feed lines to the heads, since I figure I can flush those out with some brake cleaner from up above.

Thanks again for all the tips and advice to keep this project moving!

Clair

Did you try chilling them? On some projects with press fit bearings, I've been able to pop them in by hand if you get enough temperature difference, and the clearances seem to work out better.