Engine wont crank by hand??? HELP
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Engine wont crank by hand??? HELP So I did a cam only swap with the MS4 by Texas Speed. I changed out the timing chain to a double roller timing chain set. I have not yet changed out the springs to but I did already put in the new hardened push rods. After I bolted the rockers back in place, I tried to crank the motor with a breaker bar and it cranks about 10 degrees and then it sounds like it hits something on the inside. I don't know what it is or how I could diagnose it. PLEASE HELP 
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I made sure its dot to dot top dead center. How do you check for ptv clearance? Also, before I put the rockers and pushrods back in, I spun the motor and it spun fine.
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Well I cant swap out the springs if I cant turn the motor for each piston to be at the top. If I just changed the springs just as it is, I would drop a valve into the cylinder and that would be disastrous.
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From: Shelbyville,MI
The MS4, as I recall, fails to meet minimum PTV. You may also need shorter pushrods. First, how did you measure pushrods? Second, now that the heads are on the only way to measure PTV is with the dial indicator method.
To change the valve springs, pull all the pushrods and the spark plugs. The motor should turn over at this point. Install check springs on cylinder #1 and check PTV with an adjustable pushrod and dial indicator. If PTV is OK, and I suspect it is not, then you may need to pull the heads and flycut. You can change the springs with the pushrods and spark plugs out and then install the new pushrods after the springs are changed.
To change the valve springs, pull all the pushrods and the spark plugs. The motor should turn over at this point. Install check springs on cylinder #1 and check PTV with an adjustable pushrod and dial indicator. If PTV is OK, and I suspect it is not, then you may need to pull the heads and flycut. You can change the springs with the pushrods and spark plugs out and then install the new pushrods after the springs are changed.
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Take the rockers off and see if the engine turns over. The springs are probably going into coil bind since they're not meant for that much lift. With the rockers off, the springs aren't being compressed and won't be put into coil bind.
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