My fault on the front bearing, I got it in cockeyed, I replaced it and it fits ok, but is pretty tight. Some say to stick a used cam in it and use a drift to tap on the cam until it frees up, others, and myself have used an old cam and cut a slit in the cam bearing surface the cam and used it as a bearing knife.

What is the best way to you guys?


Kasey

Old cam w/ a slit cut in the journal works for me. Other times if I know it's only one bearing and I know where it's tight, I've just used some emory cloth and loosened it up...provided I can get my big hands in there to work w/ it.

Yeah Im gonna have to pull the crank to make sure I don't get bearing crap in the journals. Just didn't know if the cam cut is the best method Its a really basic build, nothing crazy at all, just a good street cruiser with a snotty cam.

I have done the same as Chip.

You guys don't want to know what I did to my 400. The hydraulic cam that was in it was hard to get out so I knew there was no way a roller was going back in. I made a scotch brite hone and used it with the trusty old shop vac.

Buy a bearing knife and remove the shiny high spots until it turns easy
I've had to do that on more than a few blocks in my time, dang them poor Mopar castings any ways
The other option is to use a small cylinder hone on the block to get the I.D. to factory specs. using new bearings

What is the point of a new bearing if you are going to grind it down to base material?I know there are reasons to put them in but I hate the fact that this is done to make them usable.

Same here.. I do spin them with my impact while
oiling.. turns out great

It seems like such a hack job, but angle groove in old cam oil and turn it until
It turns easy. Clean up after very careful. Blow out the oil passages ect. I bought a bearing install tool, was VERY careful installing the new bearings. Careful not to damage the bearing surface! For what? So I can use an old cam to scrape for clearance!!!

If you can don't hot tank and reuse they rarely go bad I have two that were messed up so I cleaned them up with emery cloth and oil wiped it all up used a vacuum, cleaner placed a coating of wheel bearing grease and 15 years later they still work

I also use a damn nice bearing installer tool and have to clearance them...

REALLY ANNOYING!

It may seem like a lot of work to some guys but I bought my own cam bearing install tool after a Friend (my local machine speed shop) told me that big block Mopar and small block Fords were the worst. Now I install a bearing and try the cam in, install another bearing and try it in again, and so on till the job is complete. I have a special 8 inch install rod saved in my engine building tool box. Don't ask my why but since I have done this I have never had an issue.

Agree on the bearing knife. I use a piece of 3/8" square HSS lathe tool. I only use crocus cloth to polish the bearings. Cylinder hones, Scotchbrite and other stuff can imbed abrasive into the soft babbitt.

I install then check each bearing, fitting them as necessary. Keeps things a lot simpler.

I was advised to take an old cam and cut angled grooves in each journal and fill them with axle grease. I installed it, spun it 2 or 3 turns, removed, cleaned and regreased and repeated the process until it spun freely.

I had one drive me crazy a long time ago..It turned out to be that the cam had a slight bend to it.NEW stocker cam in the new box.. couldin't see it , but another new one worked just fine...

Just like everyone else here, I have an old cam with a compound angle cut with a thin ziz wheel. I have a super nice cam bearing install tool with coordinated inserts for all bearing sizes (uses a lead screw to draw them in), and sometimes it's just the block.

Now days I never use a mopar cam in anything I build, period. I don't care if it's a street cruiser, it gets BBF, or bigger, all the same size journal cam. Mostly because of the huge difference in rigidity, but also so you can hone the cam tunnel perfectly before drawing in the bearings. Presto, super tight cam bearing clearance, and friction free rotation.

Never once had a cam bearing failure from using an old cam to cut clear new bearings by the way. So anyone saying it's a hack, ok it's a hack, but it works without a flaw lol.

Have you by chance tried a different cam to see if possibly the cam you want to use is a hair off?

Ive never had to cut or alter an installed cam bearing due to a fitment issue but if I did Id do it as mentioned here and clearly its a known pitfall of mopars and cams so sooner or later im sure I will run into that one tight one.

Also, if you did cock the one bearing off the first time did it have whitness marks on it? If so it can transfer to the inner diameter and will show marks there as well.

I actually saved the one I semi jacked on install and it still worked and ran but when I pulled them I could see my install error carried over.

Here is the bearing I mentioned, if you cocked it hard enough to leave a mark on the od, it transfers to to the id and I think I used four different cams with 7500 shift points over the course of 12 years with this bearing but it never failed.

Its the front bearing which might seem like the easy one to install but until I made a short rod vs the long one with my install kit it was a pain.

It is usually not the cam bearing. It's usually the block. Chryslers aren't the only ones with the problem, there are some Ford block families that are known for poor camshaft alignment.

The block is usually at fault in one of two ways:
1. The holes for the bearings are undersized. We don't usually measure these holes, it isn't considered necessary. Yet if the holes are undersized the correct bearing will be undersized after it is installed. That's even if the bearing was perfect out of the box.
2. The block is machined in a green state, then we use it and it goes through countless heat/cool cycles. In the machined unused block the holes are lined up perfectly. But as the cycles pile up, the block's l0ocked-in stresses are relieved and the block moves a little. Now the holes aren't lined up any more. Mount the perfect bearings properly, stick in a camshaft
and it won't turn.

What would be the most correct method to fix this? Machine the block. There are cam bearings made to fit in oversize holes. But more machining is more money and more time. So fortunately there is an easier fix that still yields a usable result, that's scraping the bearings. The purists among us will use Prussian blue, jam in the camshaft and use a bearing scraper on the high spots. These are where the cam journals have rubbed the Prussian blue off. It may take a couple of tries but this method works.
The other method is to turn an old camshaft into a cutting tool by slotting the journals. This could possibly be done with engine in the car in a pinch. Scrapings would be bearing material and be caught in the intake screen or the oil filter. Purists will scoff at this approach as it's too easy and doesn't require a great deal of talent. Nevertheless, it works.

There is another way the camshaft can be hard to turn, and that is if the journals on the new camshaft are too large in diameter. Suppose the block bearing holes are at the bottom of their diameter tolerance and the bearing journals on the camshaft are at the top of their diameter tolerance. Ideally even in that situation there'd be enough clearance for the cam to turn. But if one of the dimensions exceeded the limits, you could have a camshaft that was a press fit into the bearings. That doesn't turn very easily, if at all.
Symptoms would be the old cam turns smoothly, cam bearings are not changed, and block isn't baked. Stick the new cam in and it barely turns. We know the old cam turned just fine, so the bearings should be in a pretty straight line. If the new camshaft doesn't turn easily then the journals are probably larger than the ID of the bearings.
Again the proper method to alleviate the problem is to machine down the new cam journals.

I do not support any use of abrasive on a bearing surface. There are just too many risks.

R.

I bought one of the hammer in cam bearing tools years ago, I have learn to always check the fit of the bearings on the cam before installing them If they slide onto the cam journals okay I'll install that one in the block and then install the cam into that bearings as I go, if is tight in the block I will use the bearing knife to free it up enough to rotate easily and smoothly by hand. If it has a high spot on the cam journal or the cam is bent you will know that right away
I've had probably less blocks needing the knife than those that didn't Maybe a 3 or 4 to 1 ratio, not all are bad but enough that are bad to make you remember them dang rascals
As far as using a hone, you only use the hone on the block to enlarge the hole, never on the bearings

Whew! We have all been there
There are lots of different causes and lots of ways to get around them
Mopars had cam tunnels machined "close" and the bearings were reamed at the factory from what I have been told so......
You check and correct each bearing bore--No way that a once in a while builder does that so...
you are very CAREFUL putting them in--you clean each bore with a small diameter wire brush on a long die grinder --PIA--you use WD-40 on the bearings before knocking them in--you observe that most ( not all) bearings have a very sharp edge and one that is "flatter: making IT the side you hammer on--you retighten the cam tool after every hit or two
Yo use an old stock cam that you know is straight and try it --NO cut grooves--you are either Ok or not--when you are not you pull it out and see which journal is the issue--then...you may use a cam with grooves cit with cut off wheel in the journal ( they get dull--so recut every few engines) twist it in make a mess --clean the grooves out every pass and go again--until it starts getting better--then you use your Hammer Cam--that is an old cam with No grooves--plenty of duct tape on the lobes--slide it in and use an aluminum piece about a foot long and Hammer the crap out of the cam with it in place near each journal--This works miracles to "flatten out" high spots usually near oil holes --you get it working pretty free the,,, you take a scotch brite kind of deal or very mild flapper type wheel correct diameter on a long die grinder or taped to an aluminum dowel and get in there and make them look pretty again--Ok now is the time to brake clean and clean and clean and clean until all is well--now slide that new cam in and see what you have
I have had a DOZEN Comp Cams that were CROOKED--journals measure correct--put them in a lathe and dial indicate and they are CROOKED--Blame Comp or the UPS man I don't care but it is what it is--some cams are crap out of the box
It is usually the bearings but can be the cam
Once in a while you may need to knock one out toss it and try again--that is the life of a Mopar builder
a combo of tricks is what it takes---I have never had an issue ever with what they look like after all the 'work" and FWIW I have had better luck with the Durabond HP series --they are a little harder and are harder to " work" than the tender ones but they seem to fit better for some reason