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Discussion Starter #1
Hello!
I wanted your opinion on the look of my cam bearing, does the discoloring means the bearing is bad?

Also, the camshaft seems worn only on the half of the lobes, I guess this is normal because of the small taper made for the lifters to rotate on themselves, but this seems like a pretty good difference.

let me know what you think ?

Here are the pictures:

https://www.dropbox.com/sc/guhs0cik3k8eqqz/AADCX9XonnJyYVOxGKLq-RJAa

thanks a lot!

g.b.
 

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No Pro...but looks pretty normal to me unless I'm missing something.
 

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They are supposed to rotate. But I assume you tore the motor down for a reason beyond normal maintenance What do the bottom of the lifters look like?

Big Dave
 

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The wear pattern on that cam is all wrong. First who,se cam is it and what are the specs ? What brand of lifters did you use ? what breakin oil did you use ? how did you adjust your valves .You can respond here or PM me with details of your procedure. Alex:)
 

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Discussion Starter #6
Hello!
I know I posted 2 questions buy I was mostly interested about the camshaft bearing condition.
I tore the engine apart because I need to change my camshaft. It went bad on a freshly rebuilt engine which I installed in my car but I wasn't aware that there was a proper ''break-in'' procedure... Yeah, I learnt it the hard way. The engine has ran for a total of about 4-5 hours in it's life... Shi* happens...

The cam is a CompCams XE256H (link here) http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=12-234-2&Category_Code=

I also took pictures of the lifters, some are good (those matches the few lobes which still have their original lift)
https://www.dropbox.com/sc/ov9hfatq4qk5u24/AAARGDN5aaUdu7L-D-ZNEPk_a

The engine has been rebuilt by a professional shop which I trust and that rebuilds a lot of those engines. I don't know about the brand of the lifters (probably comp cams, like the camshaft) Neither do I know about the adjustment of the valves, this was done by the shop too.
I remember that the shop did put an additive in the oil for the camshaft break-in, however, I don't know about the brand.

I am about to order a new camshaft and lifters and I would like your opinion especially about the camshaft bearings because I may change them too if you think the bearing looks bad.

I think I will stick with comp cams, same model. It seems to fit my engine and setup pretty well.

I can't really believe that a break-in procedure and oil can do such a difference on the camshaft condition but that must be what killed my camshaft.

thanks a lot guys for your time and opinions!

g.b.
 

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Discussion Starter #7
Also, would a loose lifter bore be noticeable by hand or it must be measured with specialized tools?

About the oil pressure, the gauge in my car seems to show me that I have plenty of it. I checked some time ago and I was right within specs.

thanks a lot!

g.b.
 

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Tough to tell from the pictures, but I am not really liking what I see with the cam bearings.

Has the shop that rebuilt the engine seen this up close and in person? If so, what did they say?
 

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What valve springs were used?
 

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Discussion Starter #10
The shop is unfortunately closed now, couple years ago. That is why I couldn't contact them for engine setup when I was ready to setup the engine.

For the valve springs, again, I don't know. They were installed by the shop when the engine has been rebuilt. They are supposed to be new, and, I hope, are the comp cams compatible springs...

I would like to have a second tought about the bearings

thanks again
g.b.
 

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The cam bearings are toast. Do not re-use those.

I'm an ex GM mechanic and now a Mechnical Engineer. You had a problem with the film strength of the oil being less than the load placed on the lifter and the cam lobe. It's pretty easy to see from the cam lobes. This is measured in psi. Most likely, the additive (probably advertised as zinc for cam break in) compromised the additive package and therefore the film strength of the base oil. Many many shops and hobbiest's do not understand this, and when I was a Tech I had no understanding of this either. Oil manufacturers go to great lengths to get the additive packages and base oils to work together to give you the greatest film strength possible. Adding any "additives" weakens the film strength and runs a greater risk of the damage you see. Sometimes people get away with the additives because of safety factor. Say you have and engine that requires 40,000 psi of film strength and the oil being used has a rating of 60,000 psi. Then an additive is used and the film strength is reduced to 50,000 psi. The user never knows the difference because the oil still has more film strength than what is required. I believe if you do a search that this topic has been discussed on here before.

The only reason I am sharing this is to help you understand the importance of oil choice for engine break in. I highly recommend that you use a break in oil that was formulated as such...many camshaft manufacturers offer it and I think Joe Gibbs makes some as well. Clean out the block really well and perform your rebuild. Once you're done use a good break in oil and you should have no further issues.
 

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Discussion Starter #12
heyy!

Thanks a lot for the information! I am aware of film strength as I read a lot lately on the topic of oil and read some great write-up on oil film strength.

I will be installing a comp cams camshaft and also will be using comp cams break-in oil they sell. Not their additive.

I find it pretty Odd that the engine builder would put a oil that doesn't meet the required oil film strength, they build v8 like this each weeks for years and are very reputable.

I will be checking oil pressure to be 100% sure too, maybe I have a problem with my pump not feeding the required PSI.

Is it a possibility for the oil to have lost it's properties over time? This oil has been inside the engine for a pretty long time, let's say about 5 years.

My next concern now, if the film strength wasn't good enough, is the rest of the engine. I should worry about the crankshaft bearings, the crankshaft itself, the pistons, rings, cylinders, etc etc etc?

I'm a little upset because we paid about 3000$ for the engine to get rebuilt, just to have the peace of mind about the engine condition... it seems like I am having every possible problem with it...

thanks for all inputs!

g.b.
 

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Timeline of this seems a bit off.

You had this engine custom built 5 years ago and now just got around to starting it up and breaking it in?

Did the shop give you any paperwork or parts list when you paid for it? It might help.
 

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Discussion Starter #14
Exactly... 5-6 years ago I got the engine rebuilt but only started it a for 5-10 minutes each month or so... With nothing really adjusted or tuned... Thinking that it was good for the engine to idle once in a while.

The only paperwork I got from the shop was the total receipt with a cam spec sheet stapled to it... So I'm clueless about the internals... Damn..
 

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You can change the bearings no problem and when you do use Durabond H series they are the hp ones but you will have to take the crank and pistons out as the bearings have different positions. As far as the oil goes there are two schools of thought on this with favorable results either way. I am not going to get into that debacle .Do a search on here and the Chevelle site on the subject and you head will spin with all the info . there is a breakin procedure that must be followed to a tee and you need oils that contain zddp for proper life on a flat tappet cam . there are those that will tell you to go roller I won't go for that and I wont use your brand of cam because of such problems they are noted for it. Get yourself up to par with oils and breakin procedure before you fire up your repaired engine .Do a search on team Camaro and Chevelle on xe series cams then you be the judge . Good luck keep us posted. Alex
 

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The front cam bearing is installed wrong. The oil holes in your picture are at 2:00 and 6:00 o'clock. The front cam bearing should be installed with the two holes at 12:00 and 4:00 o'clock. The other cam bearings should have the oil hole between 3:00 and 4:00 o'clock.

If the oil holes are installed between 6:00 and 7:00 o'clock the pressure of the valve springs pushing the cam down on the oil holes is like a closed valve and will starve the cam bearings for oil.
 

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The motor has to have new bearings installed so it has to come apart. It needs new bearings because the metal that used to be on the lobes was ground down into a fine powder that has embedded itself in the bearing material.

I used to build motors professionally and Comp Cams' quality dropped noticeably over the years. I had switched over to Lunati for any off the shelf cams I used (most customers refused to pay the small premium for a custom ground cam). GM chose Crane for all of their custom valve train and non-production cams; though they use Lunati for their custom cranks and longer than stock rods.

Please add together the cost of your first aftermarket cam kit and the cost of the second along with the cost of replacing the bearings; then compare that with the cost of a single roller cam with retro-fit roller tappets. Roller tappets are the industry standard now. Every car maker in the world has used for the past thirty or so years. Then think of the advantages of the roller cam in terms of added performance and ease in breaking in a motor. If you continue with flat tappets there is no guarantee that you will not wipe out another cam, requiring another rebuild.

Big Dave
 

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What Dave has to say is quite true but look at the maker of the cam that failed this tells me the quality is poor . Here again why do they offer a hardening service , To my knowledge no one else does . What does that tell you. It tells me they have a problem they don't want to fix because it cuts in on profits . We have installed about 9 F/T cams in the past 3 years none of them xe series or that brand . Two were Isky Mega cams Two Howards one Engle and one Crower . Yes some were more expensive than others none were fast ramp they all got the same break-in procedure with proper break in oil . then changed oil and filter and installed the right zddp fortified oil . There was not one problem with any of them and you could see the quality right out of the box. We also used either Johnson or Delphi lifters for all the cams . Yes roller is much better but if the quality of the cam was good it should not have let go . The engine was also professionally built . True the customer did not know of break in procedure but if the proper oil was used it should not have let go . The cam was not that radical .The other thing is when the General was using F/t Cams they never broke in one of the millions they used, why because they used good stuff and the right oil for the job. Alex
 

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Discussion Starter #20
I hear you all. Will probably dismantle the COMPLETE engine, including piston, rods, heads, etc to observe the bearings conditions...
I would like to stay with F/T cam, especially because of the price but also because I will drive that car only once in a while, I expect maybe 500-1000 miles / year... And I am also in the thinking that F/T cams have been used for decades on many engines without the problems I am experiencing.

Where could I get good advice on what camshaft to use for my setup? Also, shouldn't you be using same brand lifters/springs just to be sure everything matches perfectly?

thanks all for the help, without this forum I really don't think I could handle this...

g.b.
 
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