Cam install problem. What's wrong?
For my winter project, I'm installing a new 2002 stock GM LS6 cam in a LS1 engine that I have. I was very careful not to nick the cam bearings when I removed the old cam. When I put the new cam in it slides in easily until I reach the 4th cam bearing. I can gently coax it past that bearing, but I can tell that the cam is not spinning as freely as it should. When I get to the 5th and last bearing it will not slide on. I removed the LS6 cam and reinstalled the LS1 cam and it slide right in and turns effortlessly on the bearings, as it should, so I don't think I nicked a bearing. Can anyone tell me what the problem is? Do I have a bad cam?

I finally came to the conclusion that the cam was bad, and brought it to a local shop to have it checked. Brand new cam, .015" runout in the center. No sign of damage to the thick cardboard tube that it came in.
Thanks to everyone who replied to this thread.
I finally came to the conclusion that the cam was bad, and brought it to a local shop to have it checked. Brand new cam, .015" runout in the center. No sign of damage to the thick cardboard tube that it came in.
Thanks to everyone who replied to this thread.
Last edited by Greg_E; Jan 5, 2004 at 05:09 PM. Reason: update
i think the base circle is a tad smaller on the ls6 cam but that shouldnt effect the install. as long as your supporting the cam and gently turning during the install it should work its way in :shrug:
Originally Posted by jrp
i think the base circle is a tad smaller on the ls6 cam but that shouldnt effect the install. as long as your supporting the cam and gently turning during the install it should work its way in :shrug:
When I installed my LS6 cam it slide in with no problem. As long as you've installed a couple of your water pump bolts in the end of the cam to use as leverage. Maybe one of your lifters isn't up enough to allow the cam to slide in? Are you using the pen magnet method? If you are, install your stock cam and look at your magnets as you rotate the cam. If any of the magnets move, re-adjust them until there is no movement. I know it's frustrating as hell to get that far and run in to a problem. Hang in there and good luck !
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Have the journal concentricity checked at a machine shop with a CMM. (coordinate measuring machine) If your local auto machine shop doesn't have one, check the general shops. This is the best way to be sure. It could also be done on a surface plate or in precision v-blocks. Don't take any chances in this case.
Originally Posted by Tommy Lawson
Have the journal concentricity checked at a machine shop with a CMM. (coordinate measuring machine) If your local auto machine shop doesn't have one, check the general shops. This is the best way to be sure. It could also be done on a surface plate or in precision v-blocks. Don't take any chances in this case.
I feel for you. I just bought a cam off of Scoggin Dickey and was very upset by the lack of packaging (You'd think they'd know better). I have a friend who runs a machine shop and he said mine should be ok without checking for run-out as long as it spins freely once installed. Unfortunately, it sounds like you might not be so lucky.
Originally Posted by skonka
I feel for you. I just bought a cam off of Scoggin Dickey and was very upset by the lack of packaging (You'd think they'd know better). I have a friend who runs a machine shop and he said mine should be ok without checking for run-out as long as it spins freely once installed. Unfortunately, it sounds like you might not be so lucky.
I can tell you, a cam don't come "warped" out of the box, as someone else suggested.
If you have not completely removed the lifters (head removal), then you have a lifter that is now hanging too low.
BTW, if your old cam slid out fine, you don't have a problem with the cam bearings as long as you did not ding them afterwards.
If you have not completely removed the lifters (head removal), then you have a lifter that is now hanging too low.
BTW, if your old cam slid out fine, you don't have a problem with the cam bearings as long as you did not ding them afterwards.
Last edited by Tin Indian; Jan 4, 2004 at 02:00 PM.
I'm using the JPR cam removal tools, and they are fully inserted, so I don't see how a lifter could be hanging down. Also the old cam goes back in with no problem. I can feel the cam go into position on the last bearing but it will not go any farther onto the bearing. It's even starting to get tight on the 4th bearing, but it will go. The cam will not spin freely at this point, but will turn. I'm taking it to the shop to get it checked, but I'm pretty sure at this point it is the cam.
I've notice that on some newer cars, the lifters can get wedged into an odd position with the JPR tools and sometimes cause stuff to bind up in there. As much as I hate to suggest it, if you have pen magnets, maybe remove *one* of the jpr tools and try magnets on that side. I had to do this to get a cam in a few weeks ago...actually..I had to do that just to get the stock cam out!
My car is a '99 FRC so it is not new. Are you saying that it would be possible, to be able to take the old LS1 cam in and out (3 times) without problem, and still have a problem getting the new LS6 cam in?
Originally Posted by 99 Black Bird T/A
Could the cam be checked for warpage by rolling on a smooth surface like glass the way a push rod can be checked? How about by laying a straight edge on the cam?
Originally Posted by Greg_E
I finally came to the conclusion that the cam was bad, and brought it to a local shop to have it checked. Brand new cam, .015" runout in the center. No sign of damage to the thick cardboard tube that it came in.
Thanks to everyone who replied to this thread.
If your using the JPR tool your lifters should all be up and out of the way. I doubt that the cam was damaged during shipping especially since you say the shipping container is NOT damaged, but I guess anything is possible. Get a piece of 5/16" flat stock 2" square. Drill 3 holes in it using the 3 cam drive sprocket mounting holes as a template. Weld a 2' rod in the center of the piece of flat stock you have fabricated. Use the cam drive sprocket mounting screws to fasten your home made tool to your camshaft. Inset the cam using the tool as a handle. Now put the cam back in and when you get to the point where your having trouble you use the tool to assist you for the last two bearings. You use the tool for leverage. While spinning the tool slowly you lever the cam up and down or side to side to get it to slide in the rest of the way. You have to have a feel for these things sort of like knowing where the "G" spot is on a womans gash. Your either know or you don't





