BUMED OUT Went for a long cruise yesterday Road a little hard on the highway started to miss and a noise in the motor , ,I pulled the valve coves this mornning to find #1 cyl intake pushrod with alot of play ( they are adjustable ) cranked over very little lift so i pulled the intake and You know what i found Lobe and lifter wiped out , not even 1500 miles on it . I am running a 220-TM286H-XlH298-113A3 Its a GSCA REED Grind Hemi killer grind cam .runs 30- 60 psi oil pressure all day long, Question is What caused the cam to go again and would oil mods to lifter galley have helped Also if i remember "it has been 8 years when i tore down the same lobes were gone on the last cam" How can i stop this????
From your picture it looks like the camshaft may be located too far back in the block, the lifters are not centered on the lobes. Could there be a cam core problem or sometimes the front flange of the cam can wear into the front face of the block. Just some possibilities to check out.
The more i dig into it today i see the same thing , Ialmost got the front cover off to inspect further , When you cam core what do you mean?? Thanks Dave
In looking at picture #4 it looks like said before (core shift). If that is what it is then you have two options to fix the problem. 1. different block 2. have the block mechined to have the lifter bores corrected ($).
what about having a torrington bearing installed between the cam and block to correct the problem? or maybe go to a hydraulic roller cam where lifter rotation is not required
Thanks How do you identify a core shift problem ? I just got the cam out and it looks like some of but not all are riding off center of the lobe but only 1 lobe and lifter is gone ? bearings look good some scratches i ges from assembly but not worn. A torrington bearing behind the front cam flange is a Idea to move the cam forward . But were would i get one? Man i Hate this Motor built 8 years ago just finised a 8 year resto and now this crap
Maybe this will work, but you will need to do alot of measuring. Two important things to check: Timing chain alinement distributor gear mateing/meshing
I had a similar problem years back and ended up using the kit in the picture and a torrington bearing behind the front of the cam. this engine is still running today with the same cam and i think a board member in SoCal has it. bearing was easy to find, my parts guy measured the backside of the cam flange and found one.
Just read a post by Jim Weise about it Could it be anything else ? I think i am between a rock and a hard place on this ........Bad time to start over again , First i got to find a good core block! If i only know about this back then 8 years ago and aparently the Machine Shop did not either Thanks Guys Say tomorrow is my Birthday anyone want to donate a Good Core LOL Guess i am in denile sld he cam back in to see EYEball to get the lobes to center with the bores need to slide cam 1/6th -1/8th forward and the cam brg jurnals are out of the bearings that much to.
The lifter may be in the center. The cam lobes on the cam shaft are mechined at a slight angle that make the lifters spin. GSX1, For "only" having 1500 miles all of the lobes look pretty worn. I would also check the valve springs while you are at it. Will the lifter (s) rotate in their bores?
Yes they were rotating except the bad one I checked them out before tearing down today . I did have problems i think with the lifters after running for a 1/2 hour or so sounded like i had solids in it clattering sliightly but was always there , I also noticed after i ran this mornning that several of them bleed down quickly , befor i coud tear down, Not sure what that means ! if anything, I have a new set of LUNATI liffters i was going to put in soon , But now this. If i have a core shift problem I will need a different block . Yes it has 1500 miles on it, but the motor was built and in a running rolling chassie and Run quite a bit. once a week or so at different RPM and for long periods of time After breaking it in ,over the corse of 8 years Not sure How the Hours Add up to miles i didnot include them
Jim I read your link to this cam and its failure , i got it back around 200-2001 ,Is it possable its the cam or liffter failure?
The lifters should be "pretty" well centered over the lobe. As has been said, the profile of the lobe is higher towards one side to promote lifter rotation. From looking at the photos, the cam and lifters are not aligned well at all, putting the high point of the lobe toward the center of the lifter which will really hurt the ability of the lifter to rotate properly, and minimizes the lifter contact with the lobe. We have to find out why the lobes are not well centered on the lifters, and I don't think core shift can be blamed, here's why. We already know that when the blocks are cast the cores will have some shift, so when factory machine work is done, some features are thinner on one side than the other. BUT, when the block machine work is done, the face of the block, the lifter bores and the cylinder bores are machined in a set position regardless of where the metal is, which should ensure that the face of the block's relationship to the lifter bores should be well controlled. Unless the factory block machining itself was poorly setup for whatever reason, something else is causing a poor alignment between the cam lobes & lifters. That leaves us with a worn front block surface, incorrect cam plug installation, or bad cam core...or a rogue block that was not machined properly from the factory. Devon
DEVON Thank You i agree ,and thanks for a nother perspective that makes more sence to me All of this core shift stuff ,I understand for a race motor 500 = HP but dont think it is the case here, I am thinking a bad Cam core or grind , or cam plug instalation .The front of the block is fine ? the way it sits in the block it is very aparent that some thing alignment wise is way off I dont see how the builder missed it . and possably lifters like i said somthing was not right with them from the start always noisy even after ajusting them Like bleeding down/ticing sounded like a solid lifter cam. I THINK I HAVE TO FIRST GET ANOTHER CAM . AND TEST FIT, this is going to keep me up all night, I spent to much time and $ to be haveing this stuff happen to my new build I am off Monday i am going to examin things closer and get a new cam, as the bearings and all are fine. thanks again
Here are a couple pictures from my build. Nothing to add really, just for comparison of where the lifter rides on the cam in my block. Yours: Mine: From the otherside:
Could the cam be machined wrong? I wonder if these might help: http://www.jegs.com/i/Crower/258/66050X3-16/10002/-1?parentProductId=1145259
