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I am re-assembling my 2.0L engine after a rebuild. It has new rings and bearings. After I installed the crank, it would turn by hand smoothly and with a reasonable amount of force. When I began to install the pistons, it would not turn easily by pulling on the flywheel. I have checked the ring end gaps, and they are within spec. Is this normal for the pressure of the new rings to exert enough force on the cylinder walls as to make turning the crank by hand to be very difficult?
 

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Yes, as you install the pistons with rings the force required to turn the assembly will increase. As long as it turns 360 degrees with no dramatic changes in the force required to move it (i.e. it doesn't get noticeably easier or harder in some postions) it sounds normal.

BTW, are you using cylinder hold down clamps? You should because the same tightness of the pistons/rings can lift a liner and disturb the sealing ring at the bottom of the cylinder as you turn the crank.
 

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Yes, I used holddown clamps so the sleeves remain snug in the block. and yes I checked the rod bearing clearances with plastigage and all were within spec. So, it sounds like all is well and resistance to turning is just a natural consequence of the ring friction - good to know, and thanks for the quick responses. I'll start to button her up now...
 

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great lookng car, swirrel in the engine bay looks a wee bit suspect though.
 

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This may be too late for you now, but for future reference, when I build an engine I install the crank and check it for smothness and no tight spots when it is rotated. I install each of the rods without the piston, with the rod hanging out the bottom of the block. Then turn the crank while controling the rod to check for smothness and no tight spots. I do this for each rod in turn. Takes a lot of extra time, but no big surprises down the road if there turns out to be some slip up. If you always assume that the machine shop never makes a mistake and the parts jocky never lays down the wrong part on the counter top, you will eventually get a nasty surprise. The ONLY person you can trust in the machine shop - parts counterman - assembler chain is YOU. And sometimes YOU screws up as well. This just for what it is worth.

Best of Luck, Robert Hill in Memphis TN
 

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All is well, drag goes way up with the pistons installed and the rings dragging on those freshly honed bores. Keep up the work and send more pictures!!!
 

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I believe the pistons and the rods have a correct orientation. Small arrow ? or something on piston points toward exhaust. The rods I think have an offset. I don't remember for certain if Alfa 4 vs 6 cylinder or remembering a different engine.

But if you don't have them in correctly the consequences will not be good.

Anyone know for certain?

Wayne
 

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The big end of the rods differently have an offset and must be installed correctly. Check your rebuild manual for the correct orientation. Look at the illustration carefully as it can be confusing. If the rods, even if only one is incorrect it can actully lock up the crank.
 
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