Assembling a motor and have the crank in and torqued. I cant turn the thing at all! I used plastiguage (i know be easy on me guys) to just check on the clearances and they all spec out OK. BTW it has a rope style rear seal..I was just worried if this is common or if there is a definite problem? The piston worries are because when checking some ring gaps i noticed i could move the piston a good bit side to side (being pin sides) in the bore but not up and down when the piston is completely in the bore. It's over .030 now and i had the hyperutectic pistons pressed on the rods. Can these pistons bend out of shape when the pin is pressed through the rod? I don't assemble too many motors..especially on my own so not too sure what the "norm" is for fitments on this stuff.
Thanks
Marc

piston issue is OK, it has that clearane on the non thrust sides. On the crank, your upside down on a stand right? I'd for sure pull the caps, check for anything amiss, install/torque the caps from rear to front except #3, install it(3) snug & tap the crank front & rear to line up the(#3) thrust bearing halves then torque it (#3) too. Check turning effort as you go thru this to see if you've caught it(or to pinpoint it) & you oiled the journals after the plastigage(which can be left on there).

I first install and torque the mains without the rear seal, once I'm satisfied with the fit the crank is removed, seal installed and then the crank goes in.

Did you start with #3? Did you set it to center the thrust surfaces? Did you try to turn in after each successive addition? Plastigage does not show taper, or misalignment. Take it apart and try to turn after each. It should be able to be turned with a wratchet or breaker bar with very little effort, even with a rope seal in place. The last part should be the lower rear main seal retainer. Torque each fastener in 3 steps, ariving at the final value in one smooth motion.

Make sure all the caps are on right! Locking tabs go together.

Did you lube the mains after checking the clearance and before putting the caps back on ??

When I assemble I install the block bearing halves then "lightly" oil them before dropping in the crank. Make sure the crank spins. Wipe off as much oil as possible while spinning the crank slowly. Install caps with plastigauge and check. Clean off plastigauge residue, pull the crank, install the block part of the rear seal, lube the bearings, install the crank. Lube #3 bearing and install. Snug down - do not torque. Check end play. Lube and install the remaining bearings and caps. Start torquing and spin the crank as you go. The crank should spin by hand at all times.

If your crank doesn't spin at all you may have a serious nick in the crank that's dug itself into a bearing.

Has the block been align honed in the mains. If so, it could have the center cap cocked over to one side. When they put the main cap in the grinder to cut the ends, it may not have been square. If that is the case, then the thrust will be off and too tight when tightened. Loosen the middle main and try to spin it. Check end play before and after you tighten the cap.

Quote:

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When they put the main cap in the grinder to cut the ends, it may not have been square.

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Not likely. The way the fixture works its virtually impossible to grind it out of square. Even if they did, the bolts would hold it straight.

The caps could be on backwards though - although its hard to imagine.

Update.. i switched from the rope seal to the rubber seals and tore it down and rechecked everything. I can turn it with a breaker bar easily and i dont feel any tight spots or anything grabbing, but i cant spin it by hand. Its about 35-40 degrees in my garage and i'm using some thick lucas assembly lube. I think i'm in the clear as everything does check out like it did before, i just cant move it by hand.

If all the pistons are in place you probably won't be able to turn it with your bare hands. It should turn over smoothly with a long ratchet or a breaker bar.