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Discussion Starter #1
I still don't have my car from the shop after getting my heads and cam installed and the whole engine redone. My friend(works at the shop) said he fired up the car after the work was done and a few seconds later he heard a sound so he turned it off and later told me that a cam bearing came loose and will be replaced. He said that nothing was damaged and the cam is just fine. so im a little freaked out but should I worry about anything?
 

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DC PIT CREW BOSS
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If they are a reputable shop and stand behind their work, I wouldn't worry
 

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I still don't have my car from the shop after getting my heads and cam installed and the whole engine redone. My friend(works at the shop) said he fired up the car after the work was done and a few seconds later he heard a sound so he turned it off and later told me that a cam bearing came loose and will be replaced. He said that nothing was damaged and the cam is just fine. so im a little freaked out but should I worry about anything?
I'd ask a few questions ...

What exactly does he mean when he says a "cam bearing came loose"?

Which cam bearing was it?

Did the shop install new cam bearings when they installed the new cam?

WHY did the cam bearing pick this particular time to fail?

BEFORE they re-install the cam, they should verify that it is straight (since that may have caused the cam bearing to fail in the first place).

Personally, I would have to insist on reviewing what they find, so I'd be there for the teardown, ask the owner to explain what you observe and why it happened (and keep in mind that it COULD all be coincidental), and then how the reassembly is going to be conducted so as to prevent a recurrence of this problem. The LAST thing you want to do is worry that every time you run the car hard that you may spin a cam bearing.

Steven
 

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I don't see how it couldn't have damaged the cam. The lobes are real close to the bearring surface, if the bearring came out whie it was running, it had to guouge a lobe because it would be on top of one. Not to mention it would have caused the cam to possibly warp due to no support there. I would make them replace all the parts that are involved in the problem including the cam, or you might have premature cam failure later. And if they are giving you a guarantee on your motor, you can bet it will wait to fail just after the guarantee runs out. It sounds to me like the hole that cam bearring fits into might be a little enlarged. If that is the case, it will do it again.
 

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Discussion Starter #5
well the shop said they were going to replace the bearing and reassure me that nothing was damaged. I honestly don't know EXACTLY what happened and even though I would love to check to see what happened I work almost all day. But I do get off early and im going to stop by and see whats going on. The warranty they are giving me is a 2 year warranty on the engine but still thanks for all the advice. Ill talk to him today and see what they tell me.

im just become a little impatient because its been like 3 weeks and then this comes along. But I guess if I could do it myself I would. Ill let you guys know what happens. thanks:D
 

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cam bearing came loose ??--never happens unless the bearing installer was high on heavy shemicals (sxxx + chemicals)....look the guy in the eye and say ''so now there's a lifetime warranty on it'' and SMILE :D ...he will know that you know abt HIS prob and he'll prolly laugh too...but do the elephant thing -- never forget
 

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El Teafive
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cam bearing came loose ??--never happens unless the bearing installer was high on heavy shemicals (sxxx + chemicals)....look the guy in the eye and say ''so now there's a lifetime warranty on it'' and SMILE :D ...he will know that you know abt HIS prob and he'll prolly laugh too...but do the elephant thing -- never forget
YEah I tend to agree, unless they just swapped cams without replacing bearing and knocked one out on the R&R.

I have swapped cams without replacing cam bearings and never had issues
 

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It came loose or it spun one when he revved it up after installing your new thumper? I have put cams in without changing the bearings also, in the car I drive right now in fact. I suggested cam bearings because of the miles on the car and as long as they were in there, it wouldn't have been a bad idea.
 

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Discussion Starter #9
It came loose or it spun one when he revved it up after installing your new thumper? I have put cams in without changing the bearings also, in the car I drive right now in fact. I suggested cam bearings because of the miles on the car and as long as they were in there, it wouldn't have been a bad idea.
i think everything will be fine. I stopped by the shop yesterday and they are replaced all the bearings again and have been assembling the engine. Everything is on and looks really nice. I can't wait to get it back but im just getting a little impatient but the car is almost done so there is nothing I can do but just wait a little more...:thumbsup: thanks for your responses guys.
 

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i think everything will be fine. I stopped by the shop yesterday and they are replaced all the bearings again and have been assembling the engine. Everything is on and looks really nice. I can't wait to get it back but im just getting a little impatient but the car is almost done so there is nothing I can do but just wait a little more...:thumbsup: thanks for your responses guys.
Boy, I REALLY hope everything that they're doing with your car is on the up and up(considering the crazy crazy LOW prices)......I have to assume that since they told you that they bored the block 60 over for some new 60 over forged pistons, that they also installed new cam bearings after they cleaned everything and started the bottom end re-assembly.....properly pressing in all new cam bearings and then immediately having a problem with them upon the initial startup sounds VERY VERY suspicious(not to mention them stringing you along on the finish date over and over again)....I've been putting cam bearings in motors for close to 20 years and have "never" had anything go wrong with a properly installed set of cam bearings.....it seriously sounds like they don't have much experience in what their doing, or at the very least, they're not very good at it(or checking VITAL things along the way).....reguardless that the guys working on your car are a "friend of a friend"....I would seriously watch them like hawks from this point.....point being: if they are telling the truth and they had this kind of issue with a cam bearing, there may be several more serious issues to follow.....I understand that your not very familar with what all is involved in block machine work and the proper engine assembly technics, but building an engine "correctly" is "nothing" at all like just having some machine work done and bolting on parts.... which is really why I just recomended that you let them take care of the top end(heads and cam) and not unnessarily touch your good condition bottom end........I would also tell them you'd like to know ALL of the specs that they set your bottom end up at...IE: PISTON RING END GAPS, PISTON TO CYLINDER WALL CLEARANCE, ROD SIDE CLEARANCE, ROD BEARING CLEARANCE, MAIN BEARING CLEARANCE, VALVE TO PISTON CLEARANCE, WAS THE BLOCK DECKED? "and if so" HOW MUCH IS YOUR NEW PISTON IN THE HOLE?, WAS THE CAM DEGREE'D IN?, OR JUST THE TIMING DOTS LINED UP?.....and I would also ask the BRANDS and PART NUMBERS of EVERYTHING that they used.......if they have fairly quick "honest" answers to these questions (which they definitely should if their not just slapping things together and BS' ing you) ,this will atleast give you some piece of mind about the quality of the engine build you paid for and what your engine has in it incase further problems arrise.......post their answers to these questions or send me a PM and I'll tell you if things sound correct(and within spec)..........good luck with everything...............Joe:thumbsup:
 

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Discussion Starter #11
Boy, I REALLY hope everything that they're doing with your car is on the up and up(considering the crazy crazy LOW prices)......I have to assume that since they told you that they bored the block 60 over for some new 60 over forged pistons, that they also installed new cam bearings after they cleaned everything and started the bottom end re-assembly.....properly pressing in all new cam bearings and then immediately having a problem with them upon the initial startup sounds VERY VERY suspicious(not to mention them stringing you along on the finish date over and over again)....I've been putting cam bearings in motors for close to 20 years and have "never" had anything go wrong with a properly installed set of cam bearings.....it seriously sounds like they don't have much experience in what their doing, or at the very least, they're not very good at it(or checking VITAL things along the way).....reguardless that the guys working on your car are a "friend of a friend"....I would seriously watch them like hawks from this point.....point being: if they are telling the truth and they had this kind of issue with a cam bearing, there may be several more serious issues to follow.....I understand that your not very familar with what all is involved in block machine work and the proper engine assembly technics, but building an engine "correctly" is "nothing" at all like just having some machine work done and bolting on parts.... which is really why I just recomended that you let them take care of the top end(heads and cam) and not unnessarily touch your good condition bottom end........I would also tell them you'd like to know ALL of the specs that they set your bottom end up at...IE: PISTON RING END GAPS, PISTON TO CYLINDER WALL CLEARANCE, ROD SIDE CLEARANCE, ROD BEARING CLEARANCE, MAIN BEARING CLEARANCE, VALVE TO PISTON CLEARANCE, WAS THE BLOCK DECKED? "and if so" HOW MUCH IS YOUR NEW PISTON IN THE HOLE?, WAS THE CAM DEGREE'D IN?, OR JUST THE TIMING DOTS LINED UP?.....and I would also ask the BRANDS and PART NUMBERS of EVERYTHING that they used.......if they have fairly quick "honest" answers to these questions (which they definitely should if their not just slapping things together and BS' ing you) ,this will atleast give you some piece of mind about the quality of the engine build you paid for and what your engine has in it incase further problems arrise.......post their answers to these questions or send me a PM and I'll tell you if things sound correct(and within spec)..........good luck with everything...............Joe:thumbsup:
thanks joe. I'm thinking that I should of just done the top end but well I already asked for the whole thing so I'll just wait. Honestly its been REALLY frustrating for me because I really don't know whats going on. Im trying to be very patient because I really don't want to piss off the people working on my car. Im just trying to understand everything they tell me and take their word on it. Regardless they told me they changed all of the bearings again. I know **** happens but crap its my car! Other than the low prices I went to them because my friend recommended them and have heard that they have worked on a lot of performance cars. I did stop by on friday and saw that the whole engine is already assembled and looks really good. I love the Red Manifold!:D The front end needed to be put back(radiator,WP, Spark Plug Wires,etc) and the headers as well.

I was going to go to another friend's shop but he has been telling me that they have been getting some new mechanics and are really backed up. Some of them have messed up some engine work so that freaked me out. And this other shop I was thinking about charges A LOT for the work. Told me it was going to cost me 700 bucks just to change the cam and would need to pull the whole engine out for all of the work. As you can see I think I made the best decision I could of where I could have the work done.

Ill stop by tomorrow at the shop and see whats going on because that was friday and things should be wrapping up very soon. But then again I'm no mechanic so I don't know what else they might need to do. I just really hope I get my car and runs great! thats all I really care about....thanks for the response and ill try to find out exactly what they put in.
 

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I can't believe they pulled the radiator out to pull the engine. I did mine myself and the motor doesn't have to come close to it. I'm like JOE B, I have never heard of a cam bearring coming out on its own, and he is right, there are alot of measurements that need to be done when building an engine. Also one thing he didn't mention is if you have installed new valves in the heads and have a new cam and rockers, your whole valvetrane geometry may have changed and you may need longer or shorter pushrods to make it right again. Degreeing the cam isn't that important on a street car. That is more for getting peak performance at a particular RPM range or given condition. Usually,just for a street car you can line up the marks on the timing chain gears and be OK. But if your racing it, and trying to squeeze out every last HP you can out of your engine, then you need to degree the cam. I do hope the best for you though, and I'll keep my fingers crossed that it will be alright.
 

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I can't believe they pulled the radiator out to pull the engine. I did mine myself and the motor doesn't have to come close to it. I'm like JOE B, I have never heard of a cam bearring coming out on its own, and he is right, there are alot of measurements that need to be done when building an engine. Also one thing he didn't mention is if you have installed new valves in the heads and have a new cam and rockers, your whole valvetrane geometry may have changed and you may need longer or shorter pushrods to make it right again. Degreeing the cam isn't that important on a street car. That is more for getting peak performance at a particular RPM range or given condition. Usually,just for a street car you can line up the marks on the timing chain gears and be OK. But if your racing it, and trying to squeeze out every last HP you can out of your engine, then you need to degree the cam. I do hope the best for you though, and I'll keep my fingers crossed that it will be alright.
Yea, I previously mentioned the pushrod length to him:thumbsup: ........And, so you know, That's Not really true at all about the cam degreeing issue on LT1 engines(or really any computer controlled engines for that matter)......MANY cams (and their dowel pin placement) from the factory, and aftermarket timing chain sets are off so far, and it can mess things up "so" bad you probably wouldn't believe it.......On LT1's ,for every degree of cam timing that is off, it's double being off concerning the ignition timing........It's VERY VERY common to see aftermarket cam and timing chain sets knock the cam timing off as much as 7-10 degrees.....which in simple terms will 100% assure that that particular engine will Never run right(or anywhere near it's full potential).......I've seen many just within the last couple of years that ended up down nearly 40 HP confirmed on the "same" dyno(after the issue was corrected)..........so degreeing the cam in on these "Computer controlled" engines has "MUCH" more importance than just getting the last extra bit of horsepower out...........Just a few weekends ago I was putting in a buddies GM 847 camshaft, and Cloyes roller timing chain set.....after degreeing to check things....the cam was sitting 7 degrees retarded.......the Cloyes timing chain set (sprocket) was causing 2 of the degrees, and the poorly placed dowel pin in the cam(right from GM performance parts) was contributing to the remainder......they exchanged the cam telling me over the phone that it just plain happens from time to time(which I already knew from experience ).....the exchanged cam we got back in the mail the other day was nearly perfect(less than 1 degree off)......point being : if we diddn't degree the cam and check things, his engine would have been a big dog for sure.......this scenerio is also super common among the LT1 LT4 engine forums out there.........Joe:thumbsup:
 

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:agree: degree the cam...even totally stock engines will usually start better, make much more power, and get better mpg if the stock cam is advanced from the oem retarded ''emissions'' setting...and still pass all ''field'' tailpipe sniffer tests, altho not up to epa ''lab'' test that the manufacturer had to meet for original epa certification.
 
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