tick on fresh rebuild!!!

Going to take more measurements tomorrow, id never though 2- 1/2in breathers werent enough were there was ony a 3/4 before.....but I guess not. Anyone got a money tree?
 
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Id put the dial on each piston and bar it first, the top bearing takes the beating.
 
i just recently rebuilt my motor and found piston protusion to be 0.36 it is a 93 block i did find some info on the cummins manual tha says max piston protusion is 0.38 depending on the piston grade ,it looks like there is 3 grades of pistons a b and c with a standard gasket i have no problems with piston to head contact
 
cumminslow said:
i just recently rebuilt my motor and found piston protusion to be 0.36 it is a 93 block i did find some info on the cummins manual tha says max piston protusion is 0.38 depending on the piston grade ,it looks like there is 3 grades of pistons a b and c with a standard gasket i have no problems with piston to head contact
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He has an aftermarket cam with higher lift than you! I don't think it's the piston to head that's in question, it's his piston to valve.
 
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I see now, TurboJoe is saying that cumminslow has a Hamilton cam also. That lost me. It's not a question about the cam either, it's knowing the history of a head and how much was shaved from it, were the valve seats raised or not, etc.
 
I'm just saying he did exactly what jps just did and with the same cam too. He is just telling his findings.
 
Bullrack said:
I see now, TurboJoe is saying that cumminslow has a Hamilton cam also. That lost me. It's not a question about the cam either, it's knowing the history of a head and how much was shaved from it, were the valve seats raised or not, etc.
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Ha a minute quicker than me
 
turbojoe said:
I'm just saying he did exactly what jps just did and with the same cam too. He is just telling his findings.
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Gotcha now. I wasn't following, that comment could've been taken two ways. I know JPS says it's a new head, but what are the chances it's a reman and how much material was taken off to true it before setting on a shelf and then his machine shop shaved .004 more before install.
 
Then he's gonna need a big set of calipers to mic. the head height against a non machined head in a few spots
 
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Exactly! They are supposed to be marked with a single X every .010 removed. I also forget how much can be taken off before resetting valve seats. .030 comes to mind but I could be wrong.
 
latest and greatest info exact piston protrusion number
#1 .038
#2 .038
#3 .039
#4 .042 checked it 3 times
#5 .038
#6 .039

All the intake valve just barley tapped the pistons cant really feel an edge were the did..I tried to see if I could feel play in the rod bearings by pulling up and down on the pistons and could really feel anything or get any readings...I know my crankcase breather was and issue but if I never lost oil psi should the bearing been getting oil???
I dont understand why my clearance measurements seem high but for whatever reason there was contact. I also pulled the cam, lobes looked good. Heads at machine shop getting checked out. My only question is, should I pull the engine on check the bearings still or what??? Im not sure whatelse I can do to make sure they are all good....
 
I dont think theres a problem with the bearings, .010 HG will get you back to .028 then to deal with the P to V
 
Didn't you have the same kind of problems with the last cam ? Might just be with the piston protrusion you have could have been the problem there as well I have not read all your posts.Zack will have to chime in on what piston P he uses as a base line on this grind. Maybe wrong cam ??
 
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