Bad cam??
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Looks like normal lifters sitting on base circle Jack,, pull them one at a time and check for a slight convex shape to the lifter face that rides the cam,, put two lifters face to face and there should be a slight, very slight rock to them,, when I killed my cam as well a few of my lifters went cupped, concave,, nutz,, so I pulled the motor and someday redo it,, I have all the parts just need the time,, Matty man
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I see what you are sayin` now Jack,, this pics is bigger and i see it looks like the exhaust lifter is
sitting lower than the intake,, do you have a new lifter to compare the lifters in the block now to compare the lifter faces? Matty man
sitting lower than the intake,, do you have a new lifter to compare the lifters in the block now to compare the lifter faces? Matty man
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as stated above pull the lifter and look at the bottom of it. if the lobe is going it will kill the lifter as well and will be evident when you look at the lifter.what you see could just be casting variances in the block and lifter bore. if the lifter looks ok and the lobe isnt chewed up put a dial indicator on it and compare the lift to another lobe of the same valve
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I just removed all the rocker arms and rotated the cam by hand. Whoops! I forgot to plug up the gas line. Anyway, all 16 lifters go up and down about the same .3" like they're supposed to.
I looked at 2 lifters so far. They are not convex, nor concave. They look flat and I see the smaller circle in the center where the cam lobe rubs. I'll check the rest of them later.
I noticed that the timing chain is rubbing on the block at the very top of the cam gear. It has made a groove about 1/32" deep. I also see the cam and crank gears don't quite line up. Does someone make a spacer for that?
Jack
I looked at 2 lifters so far. They are not convex, nor concave. They look flat and I see the smaller circle in the center where the cam lobe rubs. I'll check the rest of them later.
I noticed that the timing chain is rubbing on the block at the very top of the cam gear. It has made a groove about 1/32" deep. I also see the cam and crank gears don't quite line up. Does someone make a spacer for that?
Jack
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Jack,, how far off is the crank vs the cam gear?? I am no expert by any means but I have put many sbc together and never have had a alinement issue between the two,, again i am no expert but check the crank gear to ensure the chamfer is facing the crank and it is flush on the snout,, Matty man
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Great idea! Send me $700.00.
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It looks like about 1/16" or slightly more. Recall that I said it has dug a groove in the block.
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Jack,, I am guessing you had a single chain and now running a dual timing chain? I have run into clearence issues with the thicker cam gear,, the only thing I can think of right now to give ya problems is the cam freeze plug, its a thin plug to begin with and if it is too far "in" it will not let the cam come all the way back,, not sure if this the issue you are having,, can you post a pic of the rub issue and the alinement issue?? Sucks that you are having these problems,, Matty man
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Yes. I changed to a Cloyes double roller chain.
The problem is the cam is too far back, not too far forward. That makes the gear rub on the block. I did some surfing and found that several people have had this problem. They just ground some off the block where it rubs.
About the two gears alignment -- the cam gear sits about 1/16" farther to the rear than the crank gear. Yes, the crank gear is all the way on.
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yes,, haveing to clearance the block for a double roller chain is normal with some blocks..:texas:
i never had a line up problem with a Cloyes set,,
does the block look worn behind the cam gear??
which timing chain set did you get??
Cloyes shows a .031" wear plate also,, instead of the thrust bearing at .150 thick..
http://www.summitracing.com/search/Part-Type/Camshaft-Thrust-Bearings/Make/CHEVROLET/?Ns=Rank%7cAsc
http://www.summitracing.com/parts/CLO-9-201/http://www.summitracing.com/parts/CLO-9-201/
any machine shop should be able to cut the gear down for the bearing..
i never had a line up problem with a Cloyes set,,
does the block look worn behind the cam gear??
which timing chain set did you get??
Cloyes shows a .031" wear plate also,, instead of the thrust bearing at .150 thick..
http://www.summitracing.com/search/Part-Type/Camshaft-Thrust-Bearings/Make/CHEVROLET/?Ns=Rank%7cAsc
http://www.summitracing.com/parts/CLO-9-201/http://www.summitracing.com/parts/CLO-9-201/
any machine shop should be able to cut the gear down for the bearing..
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I don's see how those wear plates work. There's no hole for the pin or bolts on the cam snout. I guess it must be smaller than the inside of the bolt circle.
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