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How hard should it be to turn a new cam over by hand

adk-roadrunner

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Hey guy's I'm in the process of trying to finish the longest engine build in history which was put on hold for several reasons. I'm building a 440 for my 73 roadrunner had the block all done by an engine builder about an hour away and he installed new cam bearings when it was done. I have the whole short block assembled and was trying to install the cam today. it went in nice and smooth until it went into the furthest back bearing and it has to be pushed in kinda hard. Once in it barely turns by hand I put the gear on and I can turn it by hard but its very hard it gets a little easier once its moving but certainly not smooth as silk. I wasn't sure if its the tons of bearing guard I put on it or what. I am super irritated with the thought of having to tear it down again or deal with trucking the block back to the machine shop. please tell me if I'm screwed.
 
I'm actually wondering if its the assembly lube I used now making it sticky. I went back out and when you get it moving it moves easier but still feels a bit sticky not rough but slow like the lube is too thick. If I stop moving it and let it sit for a few minutes its kind stuck again like its glued but once you get it moving you can move it with one hand with a little force. I'm curious if anyone has experience with clevite bearing guard or what they use on the cam bearings for install.
 
Do you know what kind of a bearing installation tool the shop used? If it's one of those universal jobs, then that might be the problem. The local shops around here usually get them in to the point the cam won't turn at all! Do you have an inch pound torque wrench? If so, put a bolt in it (single bolt cam?) and see what you get....
 
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I'm actually wondering if its the assembly lube I used now making it sticky. I went back out and when you get it moving it moves easier but still feels a bit sticky not rough but slow like the lube is too thick. If I stop moving it and let it sit for a few minutes its kind stuck again like its glued but once you get it moving you can move it with one hand with a little force. I'm curious if anyone has experience with clevite bearing guard or what they use on the cam bearings for install.
Why not pull the cam back out-wipe it off-and try it without anything on it. My guess is it will turn freely. Got nothing to lose but a few minutes of your time.
 
no inch pound torque wrench and not sure what he used to install the bearing ill try wiping off lube and try just thin oil to see what happens.
 
Just did mine not that long ago and with my home made installation tool, I could turn it quite freely with the tool.
Pull it out, wipe it off real good and look for "scuffing" on the lands. All it would take is a piece of foreign material, like a metal chip.
You can also look at each bearing from the holes in the valley. Check for any distortion or scars.
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Don't laugh.....try Lanolin also called wool wax or wool grease, is a wax secreted by the sebaceous glands of wool-bearing animals. Lanolin was a "trick" used by an old timer I knew:thumbsup:.....great for break-in.....

LANOX; A Lanolin Lubricant is a heavy duty, anti-moisture, anti-corrosion lubricant made with a high grade oil and lanolin base
 
The machine shop guy that I use told me that tight cams in big block Mopars is common. I checked around on the internet and found a solution when I had this problem. I took a worn out cam and cut diagonal grooves in the journals, then packed them with grease. The "tool-cam" was slipped in and rotated twice, removed/cleaned/regreased and then 2 more turns...After 6 revolutions, it had scraped enough off of the bearings to allow the new cam to spin much easier.
 
Just did mine not that long ago and with my home made installation tool, I could turn it quite freely with the tool.
Pull it out, wipe it off real good and look for "scuffing" on the lands. All it would take is a piece of foreign material, like a metal chip.
You can also look at each bearing from the holes in the valley. Check for any distortion or scars.
View attachment 336882
I didn't want to say anything because I always got a bunch of push back whenever I said anything about having a home made cam bearing tool too. Made it about 30 years ago and never had a problem installing cams again. Most shops want to do the bearings and freeze plus whenever you have a block cleaned and I have a hard time getting them to not do it even when I tell them I'll pay the same price so now a days if the block isn't too nasty, I'll clean it myself and avoid the hassle.
 
The machine shop guy that I use told me that tight cams in big block Mopars is common. I checked around on the internet and found a solution when I had this problem. I took a worn out cam and cut diagonal grooves in the journals, then packed them with grease. The "tool-cam" was slipped in and rotated twice, removed/cleaned/regreased and then 2 more turns...After 6 revolutions, it had scraped enough off of the bearings to allow the new cam to spin much easier.
It's common when you use a universal cam bearing tool.....
 
cleaned off bearing lube and used some 10w30 its a little easier but still turns kinda slow and sticks a little when you first start turning it.
 
This problem was also mentioned in a tech Q & A in Mopar Action magazine. Rick E wrote that the factory did not line bore the cam journals. They knocked the bearings in and if the cam was too tight, they'd bore the bearings.
Not as unusual as you might think.
 
On inspection with my build, I could see the distortion, on the leading edge of the center bearing, caused by the installation tool. It was definitely a high spot. I rigged up a rod with a fine stone and worked it out. I took all the precautions that I needed to keep any metal particles out of the oil port and the block. It pisses me off, having to fix something that someone else should have taken more care in doing.
 
This problem was also mentioned in a tech Q & A in Mopar Action magazine. Rick E wrote that the factory did not line bore the cam journals. They knocked the bearings in and if the cam was too tight, they'd bore the bearings.
Not as unusual as you might think.
Yeah, I read his article and many others that said the same. I've also read about how the 41 case pinion is the weakest one of the bunch but so far I've never broke one and never seen anyone else show be a broken one. I'll rephrase what I said about this lol....it's more prominent when you use a universal bearing installation tool :) At least IMO. One I got my own cam tool, the problem went away. I think it has something to do with the bores being on the tight side more so than them being misaligned. How do you check them for alignment though? I have another homemade tool that I check main bearing fit alignment. It seems to work pretty good but never came up with a good way to check the cam bearing fits. Another thing that most do not check is cam shaft run out. I have a brand new cam sitting here with .007 RO in the middle but it's pretty common for them to have .002-.003 RO. Somewhere along the line the one with .007 got bent or was ground that way. I don't like to straighten stock type cast cams but have done a couple of billet ones....and this might be what's happening with adk's cam.
 
I have read in several other places now about the old cam trick and cutting the diagonal slot. I have the original cam from my engine and im thinking about trying it.
 
The machinist may used a universal tool as Cranky suggested, I do not know. The new Lunati cam I had did measure slightly larger on 2 journals than the 509 I pulled out. I later installed a MP 528 that spun just fine. It may have been tight if I hadn't shaved the bearings with the "cam tool".
 
tight cam is no bueano...yes the factory used to ream the bearings on tight set ups, but you could have a bigger problem.

my block had core shift, years ago when i first built the engine, the cam was super tight.

i pulled the cam out 5k miles latter, and the #2 cam bearing cam with the cam.

my block had cam journal core shift.

Dura bond makes over sized bearings so the block can be machined and resized.

my cam slid in, and turned like butter with light engine oil.
 
Mopar's are starting to piss me off so many problems that end up being poor QC in the factory. I've decided the best way would be to make these bearings work better. I'm assuming I can't shave the bearings with the shortblock fully assembled because of debris. Super irritated if I gotta tear this thing all apart again.
 
Too many times cam bearing installers just get the job done, don't care since it's not their's. Had the same thing on mine, from a well known engine shop in my area. Besides holes not lined up right, had to do some light scraping on each for high spots.

Bad deal with short block together. Do you still have the old cam?
Might be able to use the old cam, not for scraping, but just for working it on the bearings, to 'rub' the high spots into place. Along with oil on the cam journals, between moving the old cam in and out, and around, might help to settle the bearings in, without dealing with any shavings.
 
I didn't want to say anything because I always got a bunch of push back whenever I said anything about having a home made cam bearing tool too. Made it about 30 years ago and never had a problem installing cams again. Most shops want to do the bearings and freeze plus whenever you have a block cleaned and I have a hard time getting them to not do it even when I tell them I'll pay the same price so now a days if the block isn't too nasty, I'll clean it myself and avoid the hassle.
Who cares about push back, if you have access to the tooling which I know you do then there's no reason to not make your own tool and be proud of it. I made one years ago and had no issues but now almost every motor I build gets some machine work so I pay the minimal amount and have them do it.

To answer the question, I wouldn't run a cam that doesn't spin very freely. You should be able to pull the cam and see where it's tight and carefully scrape the bearing with a knife (very carefully and do not use any type of sandpaper). The machine shop I use won't install them unless they have the cam to verify and fit the cam. Make it right so you don't have to worry later.
 
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