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Discussion Starter #1
Just put my 351w's shortblock back together again for the second time after installing the crank timing gear backwards. I cleaned the motor down throughly and blew it out with compressed air. I just put the crank and pistons in so far but the motor is now a little difficult to turn. I thought I heard from someone that the new piston rings and bearings make it hard to turn and that it's nothing to worry about. As I installed each piston the motor got progressively harder to turn. It's not binding like it was when then timing chain was bumping up against the block. When that was happening I couldn't turn it no matter how hard I pulled (the arp balancer bolt started creaking like it was gonna shear). I can move it with a 1/2" beam type torque wrench but I have to pull pretty damn hard. Once it breaks loose it'll move some then it'll get harder to turn. I guess it would be easier if i used a breaker bar and a cheater pipe I just thought it was supposed to be easy to turn.

Does it sound like I got a problem here? All my bearing clearances checked out? Is it binding up after the oil gets wiped away? I oiled the cylinder walls up before installing the pistons but haven't wiped any more on them since installing the pistons. Any help here would be greatly appreciated.​
 

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what were the main and rod clearances?

I never checked torque, but I've always been able to turn my stuff by pushing on the throws of the crank... by hand.
 

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what were the main and rod clearances?

I never checked torque, but I've always been able to turn my stuff by pushing on the throws of the crank... by hand.
after the rods and pistons have been installed? that is awfull easy.:nono: with standard tension oil rings it should be pretty stiff to turn over, getting harder with each piston installed.
 

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Discussion Starter #4
after the rods and pistons have been installed? that is awfull easy.:nono: with standard tension oil rings it should be pretty stiff to turn over, getting harder with each piston installed.
So it is normal for it to be pretty stiff then I feel better now. I can turn it it's not completely seizing up like before. There standard speed pro cast iron rings. There not broken in yet so would that be making it hard to turn? Or should it still be hard to turn after they break in. And I used plastiguage and I got around .002-.003 on the mains and around .0015 on the rods. From what I hear that's where I want to be so everything should be good there.

Thanks hopefully I won't be tearing the motor back out again like I just did:needabreak
 

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May be a dumb question, but did you use assembly lube liberally on all bearing surfaces?
 

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my engine was pretty stiff turning over by hand after i installed the rotating assembly. as long as all your bearings tolerances are within spec and your rods are installed properly i wouldnt worry about it.
 

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May be a dumb question, but did you use assembly lube liberally on all bearing surfaces?
Not dumb at all you may be on to something there. I only put a light layer of assembly lube because I've been told that too much will clog up the oil passages. Is that bs should I put a decent layer on them?
 

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Discussion Starter #8
my engine was pretty stiff turning over by hand after i installed the rotating assembly. as long as all your bearings tolerances are within spec and your rods are installed properly i wouldnt worry about it.
Cool I was worried it was suppose to spin freely like my transmission did after I rebuilt it.
 

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the main thing with assembly lube is that you don't want to leave it in to long, it will clog the filter. i tell my customers to change the filter after 10 miles or about an hour, then the oil and filter after 500 miles.
 
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